Tire pressure

Issues with shocks/springs, tires, steering box, stopping, etc.
JimmyC
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Tire pressure

Post by JimmyC »

I have 33" x 14.5" x 17" tires on Dick Cepac wheels on my 710 and am currently running 28 psi. I feel like they are over inflated, particularly in the back. I was wondering if anybody had experience with a similar set up and what tire pressure they ended up with on road and off.
Jim Chance
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krick3tt
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Re: Tire pressure

Post by krick3tt »

I run 45 to 50 on hard road w/ stock wheels
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edzz
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Re: Tire pressure

Post by edzz »

on road ~35-40
off road 15-25
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TechMOGogy
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Re: Tire pressure

Post by TechMOGogy »

Add some weight to the rear - 710's are known for being very light back there.
You can search here but they say to be very careful when braking that the rear does not swing around and pass you! :shock:
72 Pathfinder | 75 710M 2.7i | 96 350GDT Worker
63rover
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Re: Tire pressure

Post by 63rover »

To find the optimum tire pressure set all wheels to the same pressure and then draw a wide chalk line across each wheel's tread. Now dive in a straight line for a few tire revolutions. Check the lines. If the chalk has worn primarily in the center the pressure is too high. If the edges are worn, the pressure is too low. Even chalk wear is ideal. You will likely find the front and rear to have different ideal pressures.

For airing down without bead locks I like the rule of not going below 20 lbs that way if a compressor isn't available a low speed trip to the local filling station is still possible.

Have fun.

Cheers, Clive
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edzz
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Re: Tire pressure

Post by edzz »

63rover wrote:To find the optimum tire pressure set all wheels to the same pressure and then draw a wide chalk line across each wheel's tread. Now dive in a straight line for a few tire revolutions. Check the lines. If the chalk has worn primarily in the center the pressure is too high. If the edges are worn, the pressure is too low. Even chalk wear is ideal. You will likely find the front and rear to have different ideal pressures.

For airing down without bead locks I like the rule of not going below 20 lbs that way if a compressor isn't available a low speed trip to the local filling station is still possible.

Have fun.

Cheers, Clive
Good luck using that method for a Pinzgauer. :lol:
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cascade.king
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Re: Tire pressure

Post by cascade.king »

edzz wrote: Good luck using that method for a Pinzgauer. :lol:
Ha!
"Why do the back tires keep leaving 1 chalk mark, of varying width, from 15 to 45 psi!?!?"
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63rover
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Re: Tire pressure

Post by 63rover »

The chalk method worked well with 295/75/16 BFG tires (just over 33") last fall. Got the front set with even contact and a little lighter contact on the inside of the rear. Didn't have enough time to play with it further. The independent suspension does explain the rear due to the angle. I've used this method with over sized tires on Land Rovers with good results and even tire wear.

Perhaps the wiggly line is the tread?! Try drawing a wide band across the tread not with it. :lol:
63rover
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Re: Tire pressure

Post by 63rover »

I found 32 lbs was good up front and settled on 28 rear when empty (32 loaded). Very close to Ed's pressure. The tires (maker) and the temp will effect the flexibility and your results.

You will likely find as many opinions as there are members. :)
JimmyC
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Re: Tire pressure

Post by JimmyC »

My door plate indicates 2 atu in th front and 1.7 in the back. I believe that is about 28 and 24 psig respectively, much less than what people are indicating they use. I cannot find any info on the tires carrying capacity as a function of psi, but judging by the way other tires respond I think I need at least 24 psig at highway speeds. I think I will try 28 and 24 cold and see how much they rise after I run for a bit. The back end definitely has some issues with camber.
Jim Chance
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Jack Russell Racing
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Re: Tire pressure

Post by Jack Russell Racing »

I am at about 37psi for the road, and it makes a MASSIVE different in drivability, compared to the ~25psi I used to run.
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McCall Pinz
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Re: Tire pressure

Post by McCall Pinz »

I'm going to pull one springs from each side in the rear for exactly this reason. Changing tire pressure didn't help. The rear feels too stiff when empty and only OK with about 4 guys in back. I don't typically drive around with 2 pallets of materials back there.
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edzz
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Re: Tire pressure

Post by edzz »

My experience with running pressure in the mid twenty's is that it feels like i have removed the power steering belt. :lol:
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compunerdy
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Re: Tire pressure

Post by compunerdy »

McCall Pinz wrote:I'm going to pull one springs from each side in the rear for exactly this reason. Changing tire pressure didn't help. The rear feels too stiff when empty and only OK with about 4 guys in back. I don't typically drive around with 2 pallets of materials back there.
I had heard about cutting a loop out. Does just removing one work okay? Would love to not have my new tires wear funky due to the V shape.
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TechMOGogy
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Re: Tire pressure

Post by TechMOGogy »

McCall Pinz wrote:I'm going to pull one springs from each side in the rear for exactly this reason. Changing tire pressure didn't help. The rear feels too stiff when empty and only OK with about 4 guys in back. I don't typically drive around with 2 pallets of materials back there.
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72 Pathfinder | 75 710M 2.7i | 96 350GDT Worker
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