33" Tires - What tire pressure?

[WildBill]

What tire pressure are you guys with 33s running? Does it make a difference if it is an LT tire?

 

[polobuds]

45psi on my 295/70/17

 

[WildBill]

??? No one has 33s ???

 

[MUDHOE]

run 30 in the back and 32 up front. i worked for a tire shop and the owner was the most **** person i ever worked for he said 30 and 32 was the best for wear and traction i think he had 33s on his truck. but he didn't care what size it was

 

[WildBill]

thanks for the replys...keep em comin

 

[01Konvict]

Check the manufacturer of the tire and see what they say. Most of the LT tires require 45-50psi and a max of 80ish when under full load. Class C or passenger rated tires such as 275/60R20 only require around 35psi. The main difference between LT (Class D, E) and C is the steel plies in the tire itself. Therefor C = 6 ply, D = 8 ply, E = 10 ply and as the steel plies increase tire pressure does too so but also the harsher the ride. Just my .02C

 

[ThwopKing]

Start at 35psi and go from there. How wide is your wheel choice? Do you have a lot of "balooning" on the sidewall? If you go up to 40-45 and you dont like the ride quality go back down. If it seems spongy or you get a bulging sidewall you dont liek go up from there.

 

[purple 'hoe]

I run my 33's at 40psi for street use.

 

[hoe]

my 32s are at 46 psi

 

[WildBill]

8.5 inch rim. no balooning @35 psi. I am usually light (just me in it). max psi on the tire is 65 psi w/ a load of 3195lbs.

I did the chalk test and it appeared that the tire was loaded evenly. Then I went up the 42 and the chalk test appreared about the same, though the ride wa a little more harsh.

I found a calculation over on another site that determines the ideal pressure based off the tire's max load, the vehicle max weight, and the tire max pressure. It came out somewhere around 30-35 psi....which seems kind low to me.

all of the "tests" seem inconclusive or incorrect, so im here asking for opinions

 

[TheYuk]

I run my 285's at 35 they wear great and ride perfect

 

[brucebruce45]

38ish psi on SUVs, 1/2 ton truck 40ish, cars 32ish

 

[WildBill]

FYI. Nitto finally emailed back. they recommend 45 psi all around.

 

[LI99HOE]

Can't tell ya' about 33's, but I'm runnin' 35's @ 40psi on the road.

 

[MUDHOE]

go with your calculations of 30-35, 45 is way to high. when i have a trailer on ill put 45 -50 in them. like you said you did 42 and it was rough

 

[polobuds]

FYI. Nitto finally emailed back. they recommend 45 psi all around.

yep. 45psi like i said.

and my tires are 33s. 33.2 or something like that

 

[ekordas]

I run 45 all the way around.