Thank you!
So, as an idiot I’ll ask, why would Costco’s recommendation be so different?
So, as an idiot I’ll ask, why would Costco’s recommendation be so different?
Tire Pressure recommendation (1 Viewer)
- Thread starter terdrocket
- Start date
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.
gaijin
GOLD Star
Because they don't know what they are doing.
You can calculate the RCTIP yourself - it's not hard (but obviously too hard for the brainiacs at Costco) - try either of these two options:
1. The excellent monograph on tire pressure adjustments for different size/structure tires found here: Guidelines for the Application of Load and Inflation Tables
2. A very handy Tire Pressure Calculator found here: Tire Pressure Calculator
The first will afford you an opportunity to learn a lot about the science behind the calcs, while the second is the equivalent of an "Easy Button."
HTH
Could I get a recommended pressure for a non mud friend.
2013 Lexus LX570
BFG K02
LT285/55R20
Thanks you
2013 Lexus LX570
BFG K02
LT285/55R20
Thanks you
gaijin
GOLD Star
Sure.
The RCTIP for those LT285/55R20 tires on "your friend's" LX570 is 43psi F/R.
HTH
FrazzledHunter
SILVER Star
I looked through this thread for some ideas but I’m a bit unsure and this might be better for the SQOD thread but here goes. I’m running the original stock OEM Dunlop GRANDTREK AT23 285 60/R18 MSV M+S. I’ve been running 35PSI since I’ve owned my 2018LC, 15K miles on the vehicle & tires no problems. Max inflation is 51 psi.
I now have what I’m guessing is a 700lb* combined payload in the cargo area and roof. We’ll be doing normal interstate and city driving – nothing offroad.
*EDIT payload is ADDITIONAL payload - doesn't include us - add 350lbs.
I now have what I’m guessing is a 700lb* combined payload in the cargo area and roof. We’ll be doing normal interstate and city driving – nothing offroad.
- Should I air up?
- How much?
- Reset the TPMS for alarms if airing up?
*EDIT payload is ADDITIONAL payload - doesn't include us - add 350lbs.
gaijin
GOLD Star
If you check the information placard found on your Driver's door jamb, you will see info similar to this (from my 2013 LC200 for an example):
You should find on yours that the RCTIP (Recommended Cold Tire Inflation Pressure) for your OEM 285 60/R18 MSV M+S tires is the same 33psi F/R.
This is the cold inflation pressure Toyota recommends for all vehicle weights up to the GVWR (7,385 lbs) of your LC200.
1. There is no need to "air up" as long as you stay within the GVWR.
2. (See 1)
3. Reset your TPMS after setting the COLD tire pressure to the specified 33psi.
HTH
FrazzledHunter
SILVER Star
Many thanks!
I know about the sticker, and it's the same as mine - 7385 lbs. What I didn't know was if adding a few pounds would help with tire wear, heat etc...
The truck weight with me in it and a full tank of gas, no roof rack was 6160 lbs on a certified commercial scale.
Now with a loaded roof rack + cargo in the rear area + 1 passenger I'm guessing I'm at or near the GVWR.
Again many thanks.
I know about the sticker, and it's the same as mine - 7385 lbs. What I didn't know was if adding a few pounds would help with tire wear, heat etc...
The truck weight with me in it and a full tank of gas, no roof rack was 6160 lbs on a certified commercial scale.
Now with a loaded roof rack + cargo in the rear area + 1 passenger I'm guessing I'm at or near the GVWR.
Again many thanks.
Would it be possible to get recommended tire pressure for
Toyo at3 LT285/75R17 117/114Q C
And
Cooper discoverer at3 LT285/75R17 121/118S
?
Toyo at3 LT285/75R17 117/114Q C
And
Cooper discoverer at3 LT285/75R17 121/118S
?
gaijin
GOLD Star
LC200 or LX570?
Lx570. Upon searching further I think he may have answered before, I think they’re both 35 psi.
gaijin
GOLD Star
Right you are. The RCTIP for LT285/75R17 tires on an LX570 is 35psi F/R.
Never hurts to double check
HTH
nwfl4runner
GOLD Star
gaijin
GOLD Star
Sure!
The RCTIP for those Flotation 37x12.50R17LT tires on your LX570 is 25psi F/R.
HTH
nwfl4runner
GOLD Star
This is where RCTIP methodology falls apart, as it only considers load. And not handling, stability, or safety.
With such a tall sidewall, you may want to cautiously try 25PSI. If you're using your cruiser as normal for higher speed freeway use, you might find you'll want to increase it for cornering stability. Depending on your setup, tall sidewalls may roll over too easily with lower inflation pressures at speed. You can cross check it with a chalk test.
Hi Gaijin,
Would you work your magic on:
Bridgestone Dueler A/T Revo 3
123/120S M+S
Load Range E
LT275/65R18?
I see you already did 285/65r18 but I don’t find the 276/65’s.
Thank you!
Ps. Have you ever posted the method you use to derive these numbers? Teach a man to fish……. And he won’t bother you as much.
gaijin
GOLD Star
If you are asking about use on a LC200 (NOT an LX570 - that would be different) then:
The RCTIP for those LT275/65R18 tires on your LC200 is 45psi F/R.
HTH
P.S. I have tried to be transparent about the methodology and posted source material on several occasions, but it never hurts to post it again
The best summary document I have found is the excellent monograph on the subject published by Toyo Tires - found here: Guidelines for the Application of Load and Inflation Tables
Not only does it contain the Load/Inflation tables from the TRA (Tire & Rim Association), but also a detailed explanation of the calcs for going from an ISO-Metric/P-Metric OEM tire to an LT-Metric tire. You will also find a lot of general tire info that is helpful.
The "Easy Button" for those not interested in the science (a good example of which can be found in Post #1,235 above
) would be the Tire Pressure Calculator found here: Tire Pressure CalculatorPlease note that when using the calculator, it is vital that proper tire types are used - i.e., it is important to understand the difference between a P-Metric, Iso-Metric SL (Standard Load), ISO-Metric XL (Extra Load), LT-Metric, LT-Numeric, and Flotation tire. Typical "Garbage in, garbage out" scenario if the wrong tire info is input to the calculator. Please note: I have not thoroughly tested the calculator, but have found it correct for the limited times I have tested it - so use with caution.
No feelings (again I refer to post #1,235 above), just science.
P.P.S No worries, it's never a bother - always glad to help. And it never hurts to double check, right?
I’ve been going down this rabbit hole. RCTIP seems best utilized as a minimum safe pressure with an increase being necessary until the vehicle is stable and handles appropriately and you don’t exceed the maximum.
This is why I’m not too satisfied with my lt275 60 r20 k02’s…their minimum psi to meet the load handling characteristics of the oem passenger rated tire require 40-43 psi…which is jarring.
In limited testing I found that 29 psi in the k02’s felt perfect comfort wise. However this is less than the 35 psi minimum that you’re technically supposed to run an lt tire…and even at 35 with that particular tire, the load it’s graded to carry isn’t high enough to be safe for our vehicle.
Handling wise I’m not sure 29 is good yet…but all this RCTIP stuff motivated me to purchase some non light truck cooper at3 discoverer at3 4s’s in 275 60 r20 which should allow me to safely run the 29ish psi that felt good…or 33 like oem should that handle well.
Hopefully 29 psi in the non lt tires feels as squishy as 29 psi in the lt k02’s did but only time will tell.
It is ironic that a passenger rated tire is supposedly capable of a higher/safer load carrying capacity than a light truck k02 at the same 29 psi…but so it goes apparently. One wouldn’t expect that a tough lt tire would be weaker and more dangerous than a passenger rated tire.
Add to that confusion that the closest Floatation tires size to yours (33x11.5R20) “requires” 10 more PSI than the LT rated 275/60R20 and things get weird fast.
