Tire pressure on K5 with 31x10.5R15's?

[AJMBLAZER]

Guy over on Steel Soldiers is asking about the proper tire pressure for his M1009 and the 31x10.5R15's it's wearing. Wheels are the stock 15x8's the M1009's got. The military says the size should be the old 10R15LT's at 35psi but some goober sprayed the M1008/1028 pickup's psi markings of 45psi on the truck...so he's confused.

What did GM put in the trucks that came with 31's? It's been so damn long since I had my '86 I can't remember.
What do you guys run?

 

[AJMBLAZER]

 

[Drey]

Id run 35-40 on everything.

 

[AJMBLAZER]

Why so high?

 

[Drey]

Generally the tires I run on my trucks are D rated. The E rated ones on my company 2500 call for like 55 psi.

I just went out to my 91 K5 and it calls for 30 on front 31/10.5s and 35 on the rears.

 

[AJMBLAZER]

30-35. Cool.

The load rating shouldn't affect the air pressure much. It's all basically about volume and capacity of the tire.

 

[AJMBLAZER]

Hey, is your K5 a diesel or gasser?

 

[Drey]

Gasser, 350

I might still have a door off that 84 Diesel K5 I junked out but I doubt it.

 

[tRustyK5]

Right around 32 should be good. It's all about diameter, width and weight of the corner. Larger diameter and width means a larger contact patch. More area to support the weight means less pressure needed to do so. More weight needs more pressure.

Rene

 

[AJMBLAZER]

Sounds like he's going with 35 front and rear as we've figured out that's what the military says in the -10. Probably the right number considering it's got the wider rims and the 6.L.

Thanks guys.

 

[Drey]

That door is long gone so no info off it, sorry AJM

 

[AJMBLAZER]

It's cool, sounds like the guy has it figured out well. Thanks for the effort though.