What PSI are you running?

Just put on new LT tires. MAx pressure is 80 PSI. What is everyone normally running theirs at? Mine are at 70 right now and the ride seems a little squirrely to me.

 

35 for me

 

40 on highway

 

70? To me that’s too much.. I run 40 all around.

 

Around 40 should be good.

 

I've had these for over 2 years. 50 psi seems to be the sweet spot. Tried 40 and 45.

 

I run 55 in mine but, air pressure would be different for other LT tires and trucks.

If you tell us your stock size and new size (with load range) one of us can get you to the minimum safe air pressure.

 

35 cold here

 

50 to 55 and helped the gas mileage.

 

40psi on 285/75R18 Cooper AT3 XLTs.

 

Any of you towing heavy at those PSI's? I usually tow a camper around 6000lbs.

 

37 front and 41 rear. Find this to be a bit firm for the winter months. Thinking of dropping down to 35 or 37 better traction in the snow. I do get decent mpg at 37, 41. 14 mpg going 80 mph, not too bad for a Tundra.

 

What brand tires? What size? Those things factor into the sweet spot for PSI. Nonetheless I would start around 40ish and see what works for regular driving. When you're towing your trailer then bump it up but don't leave them at 70psi if you're not towing

 

New Cooper RTX. LT275/70/18

 

Alright we're getting closer.

What tires came stock and what was the cold air pressure inflation? (What does the door placard say?)

 

I had the Michelin LTX A/T2 on it. P275/65/18. They were at 36 I believe.

 

Okay, awesome. Now that we know what the truck requires for load we can find your new tire pressure...

So the Michelin LTX AT2 in that size is a SL 114 load rating
At 36PSI it carries 2601 pounds.

The Cooper RTX LT 275/70/18 is an E range 125 load rating.
At 40PSI it carries 2625 pounds.

Any lower than 40 PSI and your new tires would be considered under inflated and would not support the max gvwr of your Tundra.

I use inflation tables to find what each tire will hold at what air pressure.
https://static1.1.sqspcdn.com/static/f/589830/23447320/1378330097907/Discount+Tire+inflation.pdf

For some reason that document does not have any info for the LRE 125.
I found in this (overly complicated) document, on page 12, that the 35x12.50x17 tire has the same 125 load rating and it tells us that your tire with the 125 LR holds 2625 pounds at 40PSI.
https://www.toyotires.com/media/2125/application_of_load_inflation_tables_20170203.pdf


Hope this helps.

 

I’m running 40psi on the stock tires. I had the same size as your new shoes (BFG a/t ko) on my last truck and kept them at 40psi as well. It was the optimum pressure for ride quality, steering response and tread wear.

Both under and overinflating your tire will distort the contact patch and lead to increased tire wear. So it’s a balance.

 

Wow, Thanks for the info. Never thought it was so complicated, lol. I always just kept my tires slightly under max pressure on all my trucks. Never thought of the technical part of it.

 

I run 40-45, just have to find sweat spot for optimum tire wear, mpg and ride.