tire pressure on Nitto Ridge Grapplers

35 psi on every vehicle I have regardless of tire size or whatever. Keep it simple

 

That’s the safest bet. I have only ever had 4 and 6 ply tires, but 35psi is where I always kept them at. 10 ply would be another story.

 

I think you are missing the purpose of Load index. It has nothing to do with a manufacturer specified air pressure beyond that they would never use an air pressure that created a situation that the load capacity of the tires were lower than the vehicles GVW. Load index is important, but not necessarily for determining what pressure you should run. There is no uniformity across the tire industry that you could accurately make a claim that you run XXX brand at 35 psi while you run YYY brand at 32 because it will match their load index. These numbers that you see from the tire guys are provided by the manufacturers themselves and not provided by a 3rd party independent tester so you really can't assume that they are really accurate.

 

Not arguing that the sticker is for OEM tires. Saying that you hammering that he got his info from the dealer twice is wrong.

The difference between the advertised PSI for OEM tires and normal driving PSI on non-OEM tires is also negligible. If you’re cold at 30, you’re going to hit 34-36 at speed.. which is what everyone is going to recommend.

@Sungod - that’s the way I understand it as well. Increased tire pressure in a higher load index tire = increased load capacity to reach what that tire is rated for.

 

He never said it wasn't the dealer he talked to though either... so how do you know I am wrong, for certain, twice? Not trying to start anything! Maybe I missed the response somewhere?

I just don't have much faith when it comes to dealers (if you couldn't tell). Been to them plenty with this truck. Most of the time I leave more confused than I was before I went in haha Thats why if he heard it from a dealer i'd take it with a grain of salt. My bad for rustling feathers! Didn't mean to come off rude if i did.

 

He didn’t say he did, and it’s readily available on your door jam or in your manual. Fishing otherwise is speculation and silly.

Dealers are trash. So are most tire spots:
1) Dealer tried charging me to rotate 285s
2)Goodyear scratched my wheels balancing, then again with alignment tools, and then didn’t have the software update to print me an alignment sheet for a 2016+ Tacoma. I ended up having to inflate my tires, too

I rotate myself and check my own pressures unless I’m taking it to a reputable alignment shop and then I’ll trust.. but verify.

 

Ah, guess he could have meant Toyota as in the door jam/manual. Makes sense! I just wanted to be clear that the door jam/manual rating pertains to stock. Still close/similar to most tires around the same height/ply/structure, but not exact. All good!

I agree with you there that most are (from my experience) trash. I know there are some solid ones out there per tacomaworld, but they are not the ones near me.

Guess I'll never be going to Goodyear! ha I am not even sure where one is located near me. I am only doing the free services with the dealer then I am done. I am only doing that because I have had some problems with my rig. I figure if I do their provided maintenance it may benefit me one day if i have other issues. All in my head I suppose.

 

35 set it and forget it, give or take a couple psi but the weather usually takes care of that

 

A BFGoodrich rep told me to run 36psi on my 285/70/17 KO2.. So I think 38 might be a bit too much.

 

Nobody said dealership......Read on my friend!

 

Nope you didn’t! We cleared that up now. I just wanted to make sure no one was trusting their door jam or their dealer when it comes to aftermarket tires. Stock yes aftermarket no

Edit: their not there... fml

 

I appreciate the work...it's how i prefer to do it. But you made quite a few errors in your calculations. I think it started with using 35 psi in a P-metric for the OEM Off road tire, instead of 30 psi in a ISO/ETRTO metric with a 112SL load index.

The stock tire placard requires whatever PSI is required to attain a 2,149 lb load rating from a P-metric or ISO/ETRTO-metric tire.
The SR, SR5,and Sport use a P-metric; the Offroad uses a ISO/ETRO metric

SR/SR5-P245/75/16 109SL @ 32psi=2,172 lb
Offroad-265/70/16 112SL @ 30psi=2,149 lb
Sport-P265/65/17 110SL @ 29psi=2,149 lb

If you go to an LT the load requirement is reduced by a factor of 1.1...2,149/1.1=1,954 lbs.

 

I'll address the 4wheelparts chalk method.
It's a lot more complicated than rub some chalk on it and check wear. A lot more complicated...so much so, 4wheelparts doesn't really recommend it.
If one does the 'complete' chalk as outlined by 4wheelparts, you end up pretty dang close to the calculated load method anyway.

 

4 ply oem vs 10 ply aftermarket, i run 36-38 in my grapplers

 

You are missing it. The type of tire, load capacity, number of plys, material of plys (nylon, rayon, steel), speed rating, raised white letters, etc. have nothing to do with the air pressure. The air pressure is set by the manufacturer and it doesn't matter the type of tire you put on it. The vehicle recommended air pressure will always be the same. Why? Your truck rides on air, the tires only job is to hold the air in place (in that respect).

If I put an all steel 10 ply tire with a 100psi max, it does not change the pressure that I would run on my truck that had 4 ply passenger car tires oem. The pressure remains the same. However, I could increase that pressure to the 100psi max if I wanted and be safe from a tire pressure perspective, but it would ride like I attached steel locomotive wheels that I probably couldn't keep it on the road. I could not safely go below the vehicle manufacturers pressure that is posted on the placard.

Of course modifying your truck with new suspension parts like a heavier axle, springs, etc. would change that.

This belief that you need different air pressure with different brands and types of tires is ignorance fueled by internet legend. I mean, I read it on the internet, it has to be true, right?

BTW, my knowledge is from working in the tire industry and lots and lots of training from Michelin which probably does more product testing and research than all the other tire manufactures combined.

 

so what your saying is that I can go from a 265/70/16 (what ever the stock tire was) to a 285/75/16 cooper stt pro in an E rating and run the manufacture psi rating that's on the door and still achieve optimal tread wear?

 

Let me ask you this, have you ever walked into a 4wheelparts and seen anyone working there with a PhD? Hell, have you seen anyone working there that even graduated high school? I'm just not able to take anything they do or say with any rational sensibility.

 

You're wrong...I hope you didn't pay for that training.
BTW, Michelins have been the shittiest tire I've ever owned.

Never been in one and I try not to judge people like you apparently do.

 

Optimal? Well that is subjective and you would have to assume that the OE tire would wear optimally at the vehicle air pressure. You see vehicle manufactures are not as concerned with tire wear as much as comfort when they develop their pressure recommendation. Take a look at what Ford did with the Explorer. The pressure was way too low, but it floated like a Cadillac.

Now to answer your question with a slightly different qualification, Can you go from a 4ply tire to a E load run the same PSI and get the same tire wear? Yes. Well in theory, but in practice no. Why? Heat. Heat is the tires enemy. A 10 ply tire is a lot thicker than a 4 ply (obviously!) and it retains heat. The heat will cause the tire to wear faster. That is the reason that people think it is the air pressure. It isn't. Now, you can get your Es to last longer. How? More air pressure. Wait it sounds like I just contradicted myself. No, the increased air pressure helps dissipate the heat. You can get the same effect on your 4ply tires by bumping the air pressure, but there is usually a 35psi max so you can only go so far. On your E tires you can pack in those babies with 80psi and while you can keep them cool and make them last, you will probably lose every filling in your teeth. This is why the chalk test is so pointless, and again, why your see race teams taking tire temps and not playing with chalk.

Let's complicate your scenario even more that you want to go wider. Are you planning on getting wider wheels? By increasing the tire section width and not increasing the rim width, you are pinching the tire and this can cause a crowning effect on your tires because the shoulders don't have the space they need. 20mm is not really significant, but it will have some impact. You could lower your pressure to counter act the effect, but not sure that is a good way to go because if you have steel belted tires, you would have to take a lot out.

Remember this from newton's 3rd law "For every action, there is an equal and opposite reaction" So is true in the tire pressure world!

 

Haa, I love it! There is nothing better than the "No, you are wrong because I said so because I have absolutely nothing to support my position" response.

Listen, I am not trying to bash you or make fun of you. I apologize if I came across that way. Not my intention at all. I'm just hear to help and share my knowledge and learn as well. There are somethings I know about and MANY things I don't. That is why I probably read 10 times more than what I post. Tires I know and know well, but don't know all. If you know something that I don't about tires, please share. I am happy to learn something new.

I do reserve the right to bash 4wheelparts at any opportunity. I personally despise them and will judge them at all times.