Thinnest tire on 200 series

[gaijin]

Just curious-Where do you get 2513lbs from? Are you basing that on the stock size weight capability? The same weight LC v8 gasser in Saudi has an optional 20 inch tire with a max load of 2403 at 35 psi. I note the 4Runner does the same thing with different trims, so I am not sure the base tire is a litmus test. IIRC, my 2011 manual said something about replacing tires with the same or great max load. My 2016 manual does not (see below).

The manual says to take the load limit of the replacement tire and divide 1.10 and the result should be at least half of the GAVR or an axle. The rear axle gavr is 4300 lbs. Half of that is 2150 lbs.

Pg 466 of 2016 manual:

■Maximum load of tire
Check that the number given by dividing the maximum load by 1.10 of the
replacement tire is greater than 1/2 of the Gross Axle Weight Ratings
(GAWR) of either the front axle or the rear axle, whichever is greater.
For the GAWR, see the Certification
Label. For the maximum load of the tire,
see the load limit at maximum cold tire
inflation pressure mentioned on the
sidewall of the tire. (P. 563)

The 255/70R18 Coopers I used to run had a max rating of 2535lbs at 44psi: (2469 at 35psi)

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Dividing 2535 by 110%=2304. Or 4608 for the rear axle. 2204.5 at 35psi or 4409lbs. As such, it seems to just meet spec.

Toyo tires wrote an excellent monograph on the subject in which you can find all the info you need - see it here: Guide to Application of Load and Inflation Tables

You can also search my old posts - I'm too old and too tired to go through it all again; but what you have posted here makes little to no sense.

HTH

 

[40Man]

Toyo tires wrote an excellent monograph on the subject in which you can find all the info you need - see it here: Guide to Application of Load and Inflation Tables

You can also search my old posts - I'm too old and too tired to go through it all again; but what you have posted here makes little to no sense.

HTH

How so? I posted straight from the owners manual.

 

[gaijin]

How so? I posted straight from the owners manual.

You provided no context. What you posted by itself makes no sense. The only reason one would be dividing (or multiplying) a Load Limit value by 1.10 would be if one were changing tire types from LT-Metric to P-Metric or vice versa. The Max Load embossed on the tire sidewall has nothing to do with the tire pressure calculation. And so on...

Go online to the Toyota Owner's site, pull up the 2016 Land Cruiser Manual and post a link to the page you think is relevant so, at least, I can read the whole entry. Then, maybe tomorrow, we can discuss some more.

I suggest you take the time to read the Toyo Guide to which I posted a link in the interim.

HTH

 

[40Man]

You provided no context. What you posted by itself makes no sense. The only reason one would be dividing (or multiplying) a Load Limit value by 1.10 would be if one were changing tire types from LT-Metric to P-Metric or vice versa. The Max Load embossed on the tire sidewall has nothing to do with the tire pressure calculation. And so on...

Go online to the Toyota Owner's site, pull up the 2016 Land Cruiser Manual and post a link to the page you think is relevant so, at least, I can read the whole entry. Then, maybe tomorrow, we can discuss some more.

I suggest you take the time to read the Toyo Guide to which I posted a link in the interim.

HTH

I already did read the Toyo manual, and posted the page and text from the online 2016 manual in my first query today. It has been helpful, and I learned a lot the first time I reviewed it years ago. Thank you for posting.

And while the Toyo guide recommends replacing with at least the same rating an an OE tire, it also refers you to your owners manual regarding replacement tires, (the 2016 owners manual does not say to replace to OE tire weight limit or higher, see below), Toyota uses different OE tires for 200s with the same GAWR in other countries with a lower base max rating tire. And the heavier LX, with the same GAWR, has a lighter max weight limit OE tire than what the 255/70R18 Coopers provide. Not sure how that is not relevant.

Here it is again.

Pg 466 of 2016 manual:

■Maximum load of tire
Check that the number given by dividing the maximum load by 1.10 of the
replacement tire is greater than 1/2 of the Gross Axle Weight Ratings
(GAWR) of either the front axle or the rear axle, whichever is greater.
For the GAWR, see the Certification
Label. For the maximum load of the tire,
see the load limit at maximum cold tire
inflation pressure mentioned on the
sidewall of the tire. (P. 563)

Toyota clearly wanted a built in safety factor, so the dividing by 110% makes sense to me. And using a formula like this makes MUCH more sense that saying use OE tire load index or above, as manufacturers often spec tires with a load range in excess of the minimum. I can understand why a tire company would default to this, but a car manufacturer knows its limits and providing a calculation such as Toyota does is much more informative for a consumer.

And I never referenced the max rating on the sidewall of the tire. I listed the max ratings at certain psi's from Cooper and cross referenced to Toyo where possible. The Cooper has a 113 load index (2535 lbs at 35 psi according to Cooper and the Toyo guide for a 113 load index matches this). The Toyo guide says a standard load 255/70R18 has a 110 load index (not sure of the discrepancy, but I'll default to the manufacturer, Cooper in this case).

Truly not meaning to be argumentative, just trying to figure this out as the manual seems to be contrary to the 2513 lb rating you referenced, and the SL 113 load Toyo P255/70r18 seems to be above that at number @ 35 psi. Based on the Toyota manual, I am not sure defaulting to the 2513lb load range at a minimum is accurate.

Server Error

 

[gaijin]

I already did read the Toyo manual, and posted the page and text from the online 2016 manual in my first query today. It has been helpful, and I learned a lot the first time I reviewed it years ago. Thank you for posting.

And while the Toyo guide recommends replacing with at least the same rating an an OE tire, it also refers you to your owners manual regarding replacement tires, (the 2016 owners manual does not say to replace to OE tire weight limit or higher, see below), Toyota uses different OE tires for 200s with the same GAWR in other countries with a lower base max rating tire. And the heavier LX, with the same GAWR, has a lighter max weight limit OE tire than what the 255/70R18 Coopers provide. Not sure how that is not relevant.

Here it is again.

Pg 466 of 2016 manual:

■Maximum load of tire
Check that the number given by dividing the maximum load by 1.10 of the
replacement tire is greater than 1/2 of the Gross Axle Weight Ratings
(GAWR) of either the front axle or the rear axle, whichever is greater.
For the GAWR, see the Certification
Label. For the maximum load of the tire,
see the load limit at maximum cold tire
inflation pressure mentioned on the
sidewall of the tire. (P. 563)

Toyota clearly wanted a built in safety factor, so the dividing by 110% makes sense to me. And using a formula like this makes MUCH more sense that saying use OE tire load index or above, as manufacturers often spec tires with a load range in excess of the minimum. I can understand why a tire company would default to this, but a car manufacturer knows its limits and providing a calculation such as Toyota does is much more informative for a consumer.

And I never referenced the max rating on the sidewall of the tire. I listed the max ratings at certain psi's from Cooper and cross referenced to Toyo where possible. The Cooper has a 113 load index (2535 lbs at 35 psi according to Cooper and the Toyo guide for a 113 load index matches this). The Toyo guide says a standard load 255/70R18 has a 110 load index (not sure of the discrepancy, but I'll default to the manufacturer, Cooper in this case).

Truly not meaning to be argumentative, just trying to figure this out as the manual seems to be contrary to the 2513 lb rating you referenced, and the SL 113 load Toyo P255/70r18 seems to be above that at number @ 35 psi. Based on the Toyota manual, I am not sure defaulting to the 2513lb load range at a minimum is accurate.

Server Error

OK. I'm still enjoying my first cup of coffee, so bear with me.

Let's discuss a specific example so we do not get lost in the miasma of complicating variables. Since you linked to a Cooper Discoverer M+S winter tire, let's stick with that tire.

The Cooper Discoverer M+S winter tire in the size you are discussing is a Standard Load ISO-Metric tire 255/70R18 with a Load Index of 113. Following the procedure outlined in the Toyo Guide, this tells us that in order to use this tire on an LC200 which requires a tire with a Load Limit of 2513 lbs, we need to inflate this tire to 36psi which gives us a Load Limit of 2535 lbs which is the Maximum for this tire. So yes, if someone wants to use this tire on an LC200 they can if they inflate it to the maximum load pressure indicated on the sidewall of the tire. Is that best practice? I don't think so, but it is possible.

For this same tire, following page 466 of the manual as you cited, then when we divide the "maximum cold tire inflation pressure mentioned on the sidewall of the tire" (this is where I saw the reference, so when you say, "And I never referenced the max rating on the sidewall of the tire." I guess you are correct, you didn't reference it, but your citation from the manual did) which is 2535 lbs by 1.10 we get 2305 lbs which is, indeed, more than half the greater of the two GAWR of 4300 lbs which would be 2150 lbs. So yes, according to page 466 of the manual, the Cooper Discoverer 255/70R18 113 SL tire would be acceptable for use on the LC200.

However, if you are keen on following the manual, you should also look at page 467 where it states (emphasis mine):

●Snow tires
For driving on snow-covered roads or icy roads, we recommend using snow tires. If you need snow tires, select tires of the same size, construction and load capacity as the originally installed tires. Since your vehicle has radial tires as original equipment, make sure your snow tires also have radial construction. Do not install studded tires without first checking local regulations for possible restrictions. Snow tires should be installed on all wheels.

This directive from the manual would suggest that a winter tire like the Cooper Discoverer we're talking about should be 285/60R18 with a Load Index of 116. Clearly, the Cooper Discoverer 255/70R18 113 SL tire does not meet these criteria, most notably the Load Index, so - according to the manual - would be unsuitable for use on the LC200.

You also mentioned P-Metric P255/70R18 tires, so let's discuss those tires.

In the Toyo guide (page 19), a typical P255/70R18 tire would have a Load Index of 112 and a Maximum Load of 2469 lbs @ 35psi. So, following the directive on page 466 of the manual, we divide 2469 by 1.10 which is 2245lbs and is more than half the GAWR of 4300 lbs. So, in theory, a typical P255/70R18 112 tire would be OK for use on a LC200 if inflated to the Maximum Load pressure of 35psi.

However, following the Toyo guide, it is not possible to reach the minimum required Load Limit of 2513 lbs for this typical tire, so it would NOT be suitable for use on the LC200.

Theory is fine, but let's discuss a specific P-Metric P255/70R18 tire like the Michelin LTX M/S2 P255/70R18 112T (see here on the Michelin site: LTX M/S2).

This Michelin P255/70R18 112T tire has, according to Michelin, a Maximum Load of 2245 lbs @ 51psi. Again, following the procedure on page 466 of the manual, when we divide 2245 by 1.10 we get 2041 lbs which is less than half the GAWR of 4300 lbs and would NOT be suitable for use on the LC200. Also, following the Toyo guide, even when inflated to 50psi this tire would not reach the required Load Limit of 2513 lbs and would NOT be suitable for use on a LC200.

In conclusion:

At best, when examining the specifications of any specific tire offering, it may be possible to use some 255/70R18 tires on the LC200 if inflated to their Maximum Load pressure, but IMHO is not advisable.

It is important to understand the difference between an ISO-Metric 255/70R18 tire and a P-Metric P255/70R18 tire.

Although not discussed here, if one could find an LT-Metric LT255/70R18 tire it would probably be OK for use on a LC200.

When recommending tires for use on the LC200 it is best to discuss a specific tire offering than to generalize.

Finally, it is my opinion that when we take the contents of the Land Cruiser Owner's Manual in its entirety, it is reasonable to take the meaning as a recommendation to assure that any replacement tire have the same (or better) load capacity (read Load Index) as the tires which came stock on the vehicle.

Coffee's gone, so your turn

 

[afgman786]

You guys are having a good conversation, I wanted to add/query a couple points and try and see if this makes sense or either of you see as useful or just not useful in this context.

Australia uses a method rim that's load rating is 2500 for GVM upgrades, so to this maybe 40man is making sense that we don't need a tire at 2513lbs. Also, with an LT lets use the LT285/70/17 in this case we are running at 2315lbs which lines up with what he's referencing from Toyota manual. My question comes in with if AUS is using a rim with only a 2500lb rating for GVM upgrades wouldn't that mean the stock rim probably isn't rated that high? If so wouldn't the 2513lbs be higher than the rim capacity, meaning you could run lower and be safe?

 

[scottm]

FYI, the Recommended Cold Tire Inflation Pressure (RCTIP) for an ISO-Metric 265/70R18 116T SL tire on an LC200 is 33psi F/R. As far as Load Limit goes, should be no problem on your LC200.

HTH

Yes that helps, thanks. I'll have to go through that load inflation info to figure out how you came to 33psi. I'll run higher, at least 40psi, for better hydroplaning resistance. That might wear the center tread a bit earlier, but these are less expensive tires. The formula for hydroplaning speed I learned in military aviation was hydroplaning speed = 9 x √ inflation pressure, that was speed in knots. NHTSA calculates auto hydroplaning speed = 10.35 x √ inflation pressure. It is for when water depth exceeds tread depth. I've used it and experimented on the highway with it, seems to work with most tires I've run. I've had a 175 to 200 mile commute for 30 years, lots of time and boredom to experiment.

 

[gaijin]

You guys are having a good conversation, I wanted to add/query a couple points and try and see if this makes sense or either of you see as useful or just not useful in this context.

Australia uses a method rim that's load rating is 2500 for GVM upgrades, so to this maybe 40man is making sense that we don't need a tire at 2513lbs. Also, with an LT lets use the LT285/70/17 in this case we are running at 2315lbs which lines up with what he's referencing from Toyota manual. My question comes in with if AUS is using a rim with only a 2500lb rating for GVM upgrades wouldn't that mean the stock rim probably isn't rated that high? If so wouldn't the 2513lbs be higher than the rim capacity, meaning you could run lower and be safe?

There are a lot of unsupported assumptions in that post.

For the LT285/70R17 on the LC200, we are running 2286 Lbs because it is a substitute LT-Metric tire taking the place of an OEM P-Metric tire.

There is no evidence that the stock rim is more or less than the 2500 Lbs Load Rating of the hypothetical Method rim (link to the Method rim/specs?). How do we know that a GVM upgrade does not include the rim just as an add-on and not a required "upgrade?" I suggest we do not know.

And, no, you could not run lower and be safe.

HTH

 

[gaijin]

You guys are having a good conversation, I wanted to add/query a couple points and try and see if this makes sense or either of you see as useful or just not useful in this context.

Australia uses a method rim that's load rating is 2500 for GVM upgrades, so to this maybe 40man is making sense that we don't need a tire at 2513lbs. Also, with an LT lets use the LT285/70/17 in this case we are running at 2315lbs which lines up with what he's referencing from Toyota manual. My question comes in with if AUS is using a rim with only a 2500lb rating for GVM upgrades wouldn't that mean the stock rim probably isn't rated that high? If so wouldn't the 2513lbs be higher than the rim capacity, meaning you could run lower and be safe?

I would also point you to many of the pictures available for armored Land Cruisers which have stock wheels - here's one example:

Just Google Armored Land Cruiser 200 and see many more pics of obviously heavier than stock vehicles using stock wheels.

HTH

 

[afgman786]

@gaijin for the method rim, there was a video someone posted recently herr that had to do with potentially getting method rims and shared a YouTube video of a 200 with GVM upgrade that had methods. The guy in the video mentioned it was done along with the rest of the GVM upgrade and stated they were 2500lb rated methods. They did not mention whether it was required or an option with the package, at least that I can recall. I agree there isn't any hard evidence saying the stock rims are weaker or not, I was just going off of some of the things I had seen on YouTube and all from AUS that got me to thinking. I only posted to query your minds and have more understanding of it for me and hopefully others.

Also I agree that I've seen armored 200s running stock rims and don't question that. Even armored up though I'd assume 200 weighs around 8k, that's only 2k per corner right?

Also I get the tire discrepancy I used does take into account that its going from recommended p-metric to an LT therefore that 1.1 equation Toyo has in the charts plays into that. But seeing that the LT tire only requires a load rating lower than 2513, that is what got me thinking down this path. Maybe I'm going off of useless points here, which could be the case but worth getting a better understanding.

 

[40Man]

OK. I'm still enjoying my first cup of coffee, so bear with me.

Let's discuss a specific example so we do not get lost in the miasma of complicating variables. Since you linked to a Cooper Discoverer M+S winter tire, let's stick with that tire.

The Cooper Discoverer M+S winter tire in the size you are discussing is a Standard Load ISO-Metric tire 255/70R18 with a Load Index of 113. Following the procedure outlined in the Toyo Guide, this tells us that in order to use this tire on an LC200 which requires a tire with a Load Limit of 2513 lbs, we need to inflate this tire to 36psi which gives us a Load Limit of 2535 lbs which is the Maximum for this tire. So yes, if someone wants to use this tire on an LC200 they can if they inflate it to the maximum load pressure indicated on the sidewall of the tire. Is that best practice? I don't think so, but it is possible.

For this same tire, following page 466 of the manual as you cited, then when we divide the "maximum cold tire inflation pressure mentioned on the sidewall of the tire" (this is where I saw the reference, so when you say, "And I never referenced the max rating on the sidewall of the tire." I guess you are correct, you didn't reference it, but your citation from the manual did) which is 2535 lbs by 1.10 we get 2305 lbs which is, indeed, more than half the greater of the two GAWR of 4300 lbs which would be 2150 lbs. So yes, according to page 466 of the manual, the Cooper Discoverer 255/70R18 113 SL tire would be acceptable for use on the LC200.

However, if you are keen on following the manual, you should also look at page 467 where it states (emphasis mine):

●Snow tires
For driving on snow-covered roads or icy roads, we recommend using snow tires. If you need snow tires, select tires of the same size, construction and load capacity as the originally installed tires. Since your vehicle has radial tires as original equipment, make sure your snow tires also have radial construction. Do not install studded tires without first checking local regulations for possible restrictions. Snow tires should be installed on all wheels.

This directive from the manual would suggest that a winter tire like the Cooper Discoverer we're talking about should be 285/60R18 with a Load Index of 116. Clearly, the Cooper Discoverer 255/70R18 113 SL tire does not meet these criteria, most notably the Load Index, so - according to the manual - would be unsuitable for use on the LC200.

You also mentioned P-Metric P255/70R18 tires, so let's discuss those tires.

In the Toyo guide (page 19), a typical P255/70R18 tire would have a Load Index of 112 and a Maximum Load of 2469 lbs @ 35psi. So, following the directive on page 466 of the manual, we divide 2469 by 1.10 which is 2245lbs and is more than half the GAWR of 4300 lbs. So, in theory, a typical P255/70R18 112 tire would be OK for use on a LC200 if inflated to the Maximum Load pressure of 35psi.

However, following the Toyo guide, it is not possible to reach the minimum required Load Limit of 2513 lbs for this typical tire, so it would NOT be suitable for use on the LC200.

Theory is fine, but let's discuss a specific P-Metric P255/70R18 tire like the Michelin LTX M/S2 P255/70R18 112T (see here on the Michelin site: LTX M/S2).

This Michelin P255/70R18 112T tire has, according to Michelin, a Maximum Load of 2245 lbs @ 51psi. Again, following the procedure on page 466 of the manual, when we divide 2245 by 1.10 we get 2041 lbs which is less than half the GAWR of 4300 lbs and would NOT be suitable for use on the LC200. Also, following the Toyo guide, even when inflated to 50psi this tire would not reach the required Load Limit of 2513 lbs and would NOT be suitable for use on a LC200.

In conclusion:

At best, when examining the specifications of any specific tire offering, it may be possible to use some 255/70R18 tires on the LC200 if inflated to their Maximum Load pressure, but IMHO is not advisable.

It is important to understand the difference between an ISO-Metric 255/70R18 tire and a P-Metric P255/70R18 tire.

Although not discussed here, if one could find an LT-Metric LT255/70R18 tire it would probably be OK for use on a LC200.

When recommending tires for use on the LC200 it is best to discuss a specific tire offering than to generalize.

Finally, it is my opinion that when we take the contents of the Land Cruiser Owner's Manual in its entirety, it is reasonable to take the meaning as a recommendation to assure that any replacement tire have the same (or better) load capacity (read Load Index) as the tires which came stock on the vehicle.

Coffee's gone, so your turn

Thanks for the detailed response.

It is interesting the current manual references replacing equivalent snow tires to OE but does not mention it in regard to other tires. So if the manual is a bible we can replace a summer tire with a lesser than OE tire load as long as we meet the GAVR calculation?(the manual is long as the bible).

The other thing I will point out again is the same weight spec 200 series Land Cruiser (5.7 V8, etc.) in some other countries comes with 112 load 285/50R20 tires, as does the LX570, which has the same GAWR on the rear axle (which is the heavier of the two). Also of note, these foreign spec rigs can come with the LX type air AHC suspension, KDSS, or regular suspension. It seems to be a logical conclusion that a 112 load tire meets minimum spec for an OE equivalent.

As referenced above, car manufacturers use multiple factors, including cost when selecting tires. So sure, it is a safe bet to use a OE load rating, but if another 200 is supplied with an OE with a lower minimum load, it seems to make sense to use that as the base load.

It also makes no sense to think that any car manufacturer only installs tires with a minimum load rating. In fact, Toyota runs different load tires on exact model vehicles. The 2007 Tacoma Sport with 17" wheels came with 112 load Dunlops or a 110 Load Bridgestone Dueler.

I'll use a few other examples from vehicles I have owned:

The 5th Gen 4Runner comes with different tire options. The Limited has 245/60R20 with a 107 load, and the SR5 comes with 113 load 265/70R17. It seems insane to say the same weight capacity SR5 can't run the 107 load limited wheels because Toyota stuck on 113 load tires from the factory.

My 2013 Tundra Crewmax came with 121 Load BFG KO. The same grade truck without the Rock Warrior package came with a 114 load 275/65R18 BF Rugged trail. If I followed the manual w my Rock Warrior I couldn't run less than a 121 load, which makes no logical sense.

As Toyota puts 112 load tires on the same GVWR/GAWR Land Cruiser in other markets, it seems safe to say they are blessing 112 as an OE tire load.

Edit: one other clarification, the Cooper Discoverer has a max pressure of 44 psi, not 36 as you reference. But you are correct that you need 36 psi to get to max load according to Cooper and the Toyo chart. And that is what I ran mine at, and they had a great ride.

 

[gaijin]

Thanks for the detailed response.

It is interesting the current manual references replacing equivalent snow tires to OE but does not mention it in regard to other tires. So if the manual is a bible we can replace a summer tire that is not OE (the manual is long as the bible).

The other thing I will point out again is the same weight 200 series Land Cruiser (5.7 V8, etc.) in some other countries comes with 112 load 285/50R20 tires, as does the LX570, which has the same GAWR on the rear axle (which is the heavier of the two). Also these foreign spec rigs can come with the LX type air AHC suspension, KDSS, or regular suspension. It seems to be a logical conclusion that a 112 load tire meets minimum spec for an OE equivalent.

As referenced above, car manufacturers use multiple factors, including cost when selecting tires. So sure, it is a safe bet to use a OE load rating, but if another 200 is supplied with an OE with a lower minimum load, it seems to make sense to use that as the base load.

It also makes no sense to think that any car manufacturer only installs tires with a minimum load rating. In fact, Toyota runs different load tires on exact model vehicles. The 2007 Tacoma Sport with 17" wheels came with 112 load Dunlops or a 110 Load Bridgestone Dueler.

I'll use a few other examples from vehicles I have owned:

The 5th Gen 4Runner comes with different tire options. The Limited has 245/60R20 with a 107 load, and the SR5 comes with 113 load 265/70R17. It seems insane to say the same weight capacity SR5 can't run the 107 load limited wheels because Toyota stuck on 113 load tires from the factory.

My 2013 Tundra Crewmax came with 121 Load BFG KO. The same grade truck without the Rock Warrior package came with a 114 load 275/65R18 BF Rugged trail. If I followed the manual w my Rock Warrior I couldn't run less than a 121 load, which makes no logical sense.

As Toyota puts 112 load tires on the same GVWR/GAWR Land Cruiser in other markets,.it seems safe to say they are blessing 112 as an OE tire load.

Run whatever tire at whatever pressure you want.

Happy holidays

 

[40Man]

Run whatever tire at whatever pressure you want.

Happy holidays

Seems like a childish response when I am just trying to have a discussion to figure out requirements to answer OPs question as accurate as possible.


HTH

 

[TeCKis300]

You're not wrong @40Man. As a logical deduction based on sound fundamental reasoning, it makes great sense. There is cross cutting data that tells us otherwise.

I know @gaijin loves it when I bring up the same thing as it dilutes seemingly drum tight narrative. I appreciate what he does for the community.

At the same time, I believe we could do better and not have to suffer firmer rides than necessary as there is supporting information suggesting lower derived pressures are equally safe from a load perspective.

 

[joseywales]

What is the thinnest tire size you have run on your 200 series?

OEM size is 285/60/18, I have seen people running 275/65/18, anyone run 255/70/18?

Tundra come with 255/70/18, those have higher GVWR, what’s the advantage of thinner tire over the 285s?

I went from 285s to 255s on my 100, and found they really followed grooves on highways a ton. When I sold that 100, I put the 255s on my 2020 Tacoma and there is no pull like on the 100. I think it’s a bit too much weight for the narrow tread? Not sure if you would see a similar result on a 200, but if it IS weight related, you sure could.

 

[joseywales]

@TeCKis300 27FB in your avatar or 25?

This is my company: www.grayghostrestorations.com

 

[40Man]

You're not wrong @40Man. As a logical deduction based on sound fundamental reasoning, it makes great sense. There is cross cutting data that tells us otherwise.

I know @gaijin loves it when I bring up the same thing as it dilutes seemingly drum tight narrative. I appreciate what he does for the community.

At the same time, I believe we could do better and not have to suffer firmer rides than necessary as there is supporting information suggesting lower derived pressures are equally safe from a load perspective.

I also appreciate what he does. Reviewing the load tables has taught me a lot. I also relied on his as you say "drum tight narrative" for years, and it is clearly not as tight as he purports. I agree from a safety standpoint to stick with an OE equivalent load, even though a lower load may meet spec. As such, that is why I referenced that Toyota uses a lower spec OE load in other markets and with the LX.

It seems the Cooper I referenced exceeds all required specs and is above the OE load Toyota puts on 200 series.

The other think to keep in mind, is a lower volume/thinner tire will have a different ride at a set psi (say 36) than a wider, higher volume tire. This is magnified with bike tires, where my 2.8 plus tires run at 15 psi and my skinner 29er wheels are closer to 30 psi for an equivalent ride.

I ran the 255/70R18 Coopers at 36psi and they had a great ride. You could run them slightly lower and still meet weight requirements for GAWR and still meet the load requirements of OE equivalent tires of the LX or overseas 5.7 LC w 20" tires based on the load rate for stock psi.

This leads me to another thought, if Gaijin is using the base load and PSI from an OE equipped tire to tell people what pressure to run with larger tires, is that accurate? I know he uses different PSI for LX owners vs. 200 owners, but is that the right approach?

The LX and LC both have the same GWVR of 7385 lbs. And the same GAWR on the front and rear axles.

If someone puts RWs on their LX, why continue to use the load range from the base OE LX tire as the baseline to set pressure? Seems like there should be a range between the LX OE load range and the LC OE load range.

 

[40Man]

I went from 285s to 255s on my 100, and found they really followed grooves on highways a ton. When I sold that 100, I put the 255s on my 2020 Tacoma and there is no pull like on the 100. I think it’s a bit too much weight for the narrow tread? Not sure if you would see a similar result on a 200, but if it IS weight related, you sure could.

I ran 255s in winter on my 2011 200 with no strange tracking or pulling. I now run 275s as that is what Haakas come in, and I started adding armor to my rig so I wanted a bit extra load.

 

[TeCKis300]

@TeCKis300 27FB in your avatar or 25?
This is my company: www.grayghostrestorations.com

Good eye. She's a 27FB Ocean Breeze that I've spent lots of time modifying thanks to the also great community there. Thanks for sharing the link and I'm enjoying the frame off restoration pics!

I also appreciate what he does. Reviewing the load tables has taught me a lot. I also relied on his as you say "drum tight narrative" for years, and it is clearly not as tight as he purports. I agree from a safety standpoint to stick with an OE equivalent load, even though a lower load may meet spec. As such, that is why I referenced that Toyota uses a lower spec OE load in other markets and with the LX.

It seems the Cooper I referenced exceeds all required specs and is above the OE load Toyota puts on 200 series.

The other think to keep in mind, is a lower volume/thinner tire will have a different ride at a set psi (say 36) than a wider, higher volume tire. This is magnified with bike tires, where my 2.8 plus tires run at 15 psi and my skinner 29er wheels are closer to 30 psi for an equivalent ride.

I ran the 255/70R18 Coopers at 36psi and they had a great ride. You could run them slightly lower and still meet weight requirements for GAWR and still meet the load requirements of OE equivalent tires of the LX or overseas 5.7 LC w 20" tires based on the load rate for stock psi.

This leads me to another thought, if Gaijin is using the base load and PSI from an OE equipped tire to tell people what pressure to run with larger tires, is that accurate? I know he uses different PSI for LX owners vs. 200 owners, but is that the right approach?

The LX and LC both have the same GWVR of 7385 lbs. And the same GAWR on the front and rear axles.

If someone puts RWs on their LX, why continue to use the load range from the base OE LX tire as the baseline to set pressure? Seems like there should be a range between the LX OE load range and the LC OE load range.

The load derived inflation pressures are a solid baseline from which to start from. I absolutely agree with you, and it's a point that I also reiterate. Pressures can and should be further adjusted for other factors. The cross data tells us it's very likely that the LC factory pressures were tailored up from base load pressures for things like Dunlop Grandtrek AT23 tire traits, tire wear, sidewall rollover, handling, etc.

Strict load inflation tables tells me to use 35psi for my 35x12.5s. For my particular Toyo ATIII tire fitment, handling feedback (calibrated from my track days) tells me that it's not enough pressure to keep the sidewalls from rolling over under cornering for my driving style. To your point, I tailor my pressures up a few PSI from there. When I tow, even though tire pressure already more than meet necessary load ratings, I still go up a few PSI from that. Yet I'm not afraid to cruise highways at say 30 PSI when I'm completely unladen transiting between off-road segments, because load derived base pressures are good up to the full chassis load, max speed, on the hottest of summer days.

A potential methodology for any fitment would probably be the start with the heavier LX derived pressures as a safe min load basis for the 200-series chassis. Then tailor up from there. Stiffer carcass tire models or wider wheel and tire fitments may not need anymore pressure. Taller narrow tires may demand more. More armor and weight, may want more pressure. Etc.

 

[Lester did that]

So what's the final agreement? Is there one? Lot's of talk about numbers, charts, psi, ratios, banter and theory. Who is running tall and skinny on a built up LC200? Real world. Not spread sheet numbers. Not to sound crass.

I am swearing this up and down. I used to drive discos and I swear its tyre size. You can put on a 8.5 x 34 and they just go thru anything. These new LC's are great but the damn tyres are too big for off road on a stock rim width. My better half agrees. She is the one who purchased the new set. She has been screaming and screaming about the tyres available here in the states. In fact I think it's the only thing that makes her upset. Tyres and wheels.

So let the tyre debate continue.