Tire Pressure recommendation (2 Viewers)

[gaijin]

Sensei,

This is a bit off-topic, but could you give the recommended tire pressure for an 80 series on Cooper Discoverer STT LT285/65R16 load range D?

I've been running 35 psi but recently switched to 32 psi because the ride was much more comfortable. After reading all the info here about LT-metric tires requiring higher cold tire inflation pressures, I fear that I may have been underinflated all along. I've already had one of these Coopers blowout on the highway once (sidewall blew) and now I'm thinking it might have been due to the tire pressure?

You do pose interesting questions.

I can find no Cooper Discoverer STT tire in size LT285/65R16. In fact, the Cooper Tires web site lists NO tire in that size. Further, the Tire and Rim Association Yearbook - the "bible" of tire pressures and load limits has no information on any tire in that size.

Are you sure your tire is that size?

All I can offer is that the ABSOLUTE MINIMUM Recommended Cold Tire Inflation Pressure for ANY LT-Metric tire on ANY vehicle is 35 psi, so IF you do indeed have an LT-Metric tire, then you are most probably underinflated at 35 psi.

Please double check the tire size and re-post.

HTH

 

[HRTROB]

You do pose interesting questions.

I can find no Cooper Discoverer STT tire in size LT285/65R16. In fact, the Cooper Tires web site lists NO tire in that size. Further, the Tire and Rim Association Yearbook - the "bible" of tire pressures and load limits has no information on any tire in that size.

Are you sure your tire is that size?

All I can offer is that the ABSOLUTE MINIMUM Recommended Cold Tire Inflation Pressure for ANY LT-Metric tire on ANY vehicle is 35 psi, so IF you do indeed have an LT-Metric tire, then you are most probably underinflated at 35 psi.

Please double check the tire size and re-post.

HTH

Oops sorry for that. I'ce corrected my post. I meant LT285/75R16 Load range D Cooper Discoverer STT on a 1996 LC 80 series

 

[gaijin]

Oops sorry for that. I'ce corrected my post. I meant LT285/75R16 Load range D Cooper Discoverer STT on a 1996 LC 80 series

OK, that sounds better.

Since I do not provide info for vehicles other than 200 series, and am making a special one-time exception in your case, what I need from you is the following info from the door sticker on your 1996 LC80:

- OEM Tire size (exactly as it is written on the sticker)
- Tire Inflation Pressure(s) for Front and Rear
- GVWR
- GAWR for Front and Rear

With all that info, I can offer an inflation pressure(s).

HTH

 

[gaijin]

Oops sorry for that. I'ce corrected my post. I meant LT285/75R16 Load range D Cooper Discoverer STT on a 1996 LC 80 series

I dug a little deeper in my records and found some LC80 info.

Does your 1996 LC80 have this info on the door sticker?

OEM Tire Size: P275/70R16 114S
Tire Inflation Pressure: 32psi F/R

If so, then the Recommended Cold Tire Inflation Pressure for your LT285/75R16 tires on your 1996 LC80 is 38psi F/R.

So yes, you are definitely underinflated at 35psi and dangerously so at 32psi.

HTH

 

[HRTROB]

I dug a little deeper in my records and found some LC80 info.

Does your 1996 LC80 have this info on the door sticker?

OEM Tire Size: P275/70R16 114S
Tire Inflation Pressure: 32psi F/R

If so, then the Recommended Cold Tire Inflation Pressure for your LT285/75R16 tires on your 1996 LC80 is 38psi F/R.

So yes, you are definitely underinflated at 35psi and dangerously so at 32psi.

HTH

Thank you very much!! My 80 doesn't have a sticker on the door jamb so I had to bust out the owner's manual. I found the factory tire pressure recommendation but no mention of GVWR and GAVR, just vehicle length and height measurements.

I'll try 38 psi although I have a feeling it's going to be bone-jarring! Thank you once again Sensei Gaijin

 

[gaijin]

Thank you very much!! My 80 doesn't have a sticker on the door jamb so I had to bust out the owner's manual. I found the factory tire pressure recommendation but no mention of GVWR and GAVR, just vehicle length and height measurements.

I'll try 38 psi although I have a feeling it's going to be bone-jarring! Thank you once again Sensei Gaijin

View attachment 1626943

Your manual confirms the info I had for tire size and recommended pressure for the stock tires.

Please remember, anything less than the recommended 38psi for your LT285/75R16 tires is unsafe. Sorry if you find it "bone-jarring" - it is what it is.

HTH

 

[Markuson]

Your manual confirms the info I had for tire size and recommended pressure for the stock tires.

Please remember, anything less than the recommended 38psi for your LT285/75R16 tires is unsafe. Sorry if you find it "bone-jarring" - it is what it is.

HTH

Sounds like a suspension adjustment might be in order if it's still that jarring at the proper PSI.

 

[indycole]

New LT285/70r18 Nitto Ridge Grapplers going on tomorrow.

@gaijin Any chance you can work your wizardry on the CTIP for this tire size? I’ve done a couple searches but didn’t find anything.

Also, for academic purposes, what would the theoretic CTIP be if the truck is over GVWR by 500-750 lbs? Hypothetically, of course.

 

[gaijin]

New LT285/70r18 Nitto Ridge Grapplers going on tomorrow.

@gaijin Any chance you can work your wizardry on the CTIP for this tire size? I’ve done a couple searches but didn’t find anything.

Also, for academic purposes, what would the theoretic CTIP be if the truck is over GVWR by 500-750 lbs? Hypothetically, of course.

The Recommended Cold Tire Inflation Pressure for the LT285/70R18 tires on your LC200 is 38psi F/R.

HYPOTHETICALLY, and I don't like hypotheticals, if you want to know how much more load each of these new tires MIGHT be able to handle at higher than recommended pressures, then one MIGHT consult the following chart:

Stock LC200 / 38psi / 2309 lbs/tire
172 pounds over stock LC200 / 39psi / 2352 lbs/tire
344 pounds over stock LC200 / 40psi / 2395 lbs/tire
508 pounds over stock LC200 / 41psi / 2436 lbs/tire
672 pounds over stock LC200 / 42psi / 2477 lbs/tire
836 pounds over stock LC200 / 43psi / 2518 lbs/tire

I DO NOT RECOMMEND ANY OF THE PRESSURES SHOWN IN THIS CHART WHICH DIFFER FROM THE RECOMMENDED COLD TIRE INFLATION PRESSURE OF 38psi.

Hypothetically, of course.

HTH

 

[indycole]

Thanks! 38 PSI it is. I'll keep those other numbers handy just in case, though.

 

[earthsurfer]

Can I get a psi recommendation for BFG AT T/A KO2 LT285 60 R18 D1 on an 08 LC ?

 

[gaijin]

Can I get a psi recommendation for BFG AT T/A KO2 LT285 60 R18 D1 on an 08 LC ?

Sure.

Recommended Cold Tire Inflation Pressures for your LT285/60R18 118/115S D tires on your 2008 Land Cruiser are 45psi Front / 47psi Rear.

HTH

 

[earthsurfer]

Sure.

Recommended Cold Tire Inflation Pressures for your LT285/60R18 118/115S D tires on your 2008 Land Cruiser are 45psi Front / 47psi Rear.

HTH

Righton! I've been running them at 33 psi for close to 55k miles now, this will be quite a different ride I'm sure

Thank you !!

 

[gaijin]

Righton! I've been running them at 33 psi for close to 55k miles now, this will be quite a different ride I'm sure

Thank you !!

And a lot safer!

HTH

 

[earthsurfer]

And a lot safer!

HTH

I just found the receipt from America's Tires. I see they put down 45psi in both front and rear. I'm curious about the 2 psi difference in your recommendation. Thank you!

 

[gaijin]

I just found the receipt from America's Tires. I see they put down 45psi in both front and rear. I'm curious about the 2 psi difference in your recommendation. Thank you!

You need look no further than the sticker on your door jam - it will show the Recommended Cold Tire Inflation Pressures for your stock P285/60R18 tires as 32psi Front / 34psi Rear. This calcs out to thge pressures I recommended for you - 45psi Front / 47psi Rear.

Why did America's Tires put down the wrong tire pressure for your rears? You'll have to ask them why they made that mistake.

I'm more curious how you managed to run those tires at 33psi F/R for 55 thousand miles when you had a dramatically different recommended pressure from Discount Tire (45psi F/R) AND a door placard that had different pressures for front and rear.

Glad you are concerned now, and glad we could get you back in the safe zone for pressure.

HTH

 

[Roy Park]

Thanks for this thread gaijin. I found the recommended pressure for my tires for the LC. Now I’m curious what it is for the tires in my Tundra. They are Toyo RT 35/12.5 R17 121Q Load E.

Thanks in advance.

 

[Chrisleduc1]

What is proper pressure for the Michelin Defender LTX M/S 285/60/20 installed on an ‘18LX ??

Thanks !!

 

[canyonrider]

Sure.

Recommended Cold Tire Inflation Pressures for your LT285/60R18 118/115S D tires on your 2008 Land Cruiser are 45psi Front / 47psi Rear.

HTH

Wait! What’s up with different front and rear pressures here? Is that specific to the 2008? I have a 2009 LC with these tires that I run at 46 psi F/R per earlier posts and other threads.

 

[gaijin]

Thanks for this thread gaijin. I found the recommended pressure for my tires for the LC. Now I’m curious what it is for the tires in my Tundra. They are Toyo RT 35/12.5 R17 121Q Load E.

Thanks in advance.

For the Tundra, you're on your own - I just do 200 series; but you can find all the info you need in this publication: https://toyo-arhxo0vh6d1oh9i0c.stac...ication_of_load_inflation_tables_20170203.pdf

HTH