Tire Pressure Question

My door jamb recommends 35psi front and rear. I just put new tires on my truck, and they have a max cold pressure of 80psi (MICH DEFENDER PLATINUM LT265/60R20 LRE). Tire installer set them to 48psi. Just curious about the huge gap between what Toyota recommends and the max cold pressure of the tire? Also wondering how low or high the pressure would have to go to trigger the TPS sensor? Is the higher psi rating on the tire just for towing heavy loads?

 

Yeah high psi usually for towing. People usually do something around 35 to 40 cold depending. I live in a hot area and my contact patch is great at 35 psi in back and 40 up front.

 

Short answer (to the last question) is yes.
You don't need, or want to run at 80 psi if you aren't hauling or towing heavy.
Tires will wear poorly and ride quality will seriously suffer.

Toyota puts Standard Load rated tires on as O.E.
Your Michelins are "E" rated 10-plys. MUCH higher load capacity and also rated for higher pressure.

I run my Cooper E's (also max 80 psi) at 35 to 38 when not towing.

I still don't have my TPMS reading correctly....

 

Load range E tires (80psi max) have a much higher load capacity than the OEM tires.

Load range E tires have thicker sidewalls (and usually deeper tread) that allows them to operate at the much higher pressures. At lower loads (i.e. a normal Tundra weight) the tires should operate at similar pressures as lower load range tires.

As for TPMS, they should be reset to the indicated/appropriate tire pressure.

 

Just know that your new E range LTs do not support the same amount of weight at 35 psi as your P rated stock tires did. There's a chart that shows the weight carrying capability of each tire at specific PSI values. If you are going to load up at all, know how much you are carrying and how much you need to inflate to do so safely. even 40psi can be underinflated and cause tire problems on your new LTs if carrying a lot of weight. 20" tires option wasn't available on this calculator, but as an example....

 

Thanks for the feedback. I will definitely pay more attention to tire pressure when towing our inshore boat (and offshore boat next year).

 

How are you liking the defender platinums?

 

They are great! Will be towing our inshore boat a bunch this next week so I will see how they perform.

 

I went from P rated tires and door jamb said 30 front and 33 back. Went to LT and did that calculator and it calls for 42 front and 45 back and they ride well. Definitely use that calculator.

 

I’m loving mine as well. Maybe lost 1/2 mpg but hard to tell. How’s you mpg been?

 

The max psi is universal for the tire. Not the truck. That tire can be installed on a Tacoma, or an f450. If this tire were on an f450 with a pallet of bricks in the bed, towing a gooseneck with 20,000 lbs on it, they would need to bump the psi up to handle the weight of the load. Your 1/2 ton truck will never carry nor tow anything that will warrant the need to put 80 psi in the tires. For normal daily driving, you shouldn’t need any more than 37-40 psi. If you’re towing/carrying a heavy load, you can bump your to 50-55. But you will never need to increase the psi past this, as the capacity of the truck just isn’t there.

 

I have Toyo AT2 E rated tires and have the air pressure set @ 45 psi at all 4 tires

 

There is a conversion calculator you do online, I would use that as a guide and go from there.

chalk testing is another option to really dial it in.

 

New tires were awesome! I also had air bags installed, put them up to 28lbs to get the truck level with the inshore boat on the hitch. Rode perfectly. Tires are at 46 lbs.