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Old 10-22-2011, 02:34 PM   #1
Andy4639
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Question Air Pressures

OK guy's,

I know we all have talked about our wheels and what not but what about tire pressures for them. I'm wondering what everyone is running.

My 20" tires say 51PSI max. on the fronts. The rear 20" say 50PSI Max.

I have 40 PSI in the fronts and 30 PSI in the rears.


Fronts:



Rears:


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Get out and drive the truck this summer and have some fun!
It sucks not being able to hear!

LWB trucks rule, if you don't think so measure your SWB!
After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.
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Old 10-22-2011, 06:54 PM   #2
airdale94
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Re: Air Pressures

I wouldn't run less than 40psi front or rear on those low profile tires. I'm thinking 40 front 45 rear. If it's to harsh a ride you could try 35 front 38 rear. With the way the roads are today you'll bend up your rims running 30 psi. I work in a tire shop and I see bent rims all the time from people hitting potholes with low profile tires and not enough air. I would run as close to max as possible. Keep an eye on tire wear though.Some cheaper tires don't take to running at max psi, they will wear in the center of the tread. Not saying those Invos are cheap, I'm not familar with all the newer HP aftermarket brands.
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Old 10-22-2011, 07:40 PM   #3
Andy4639
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Question Re: Air Pressures

airdale94,
This is the kind of info I'm talking about. I was walking by the truck at the bank yesterday and said to myself the fronts looked a little low. When I got home and forgot about them until this morning when sitting in the garage they both looked low. The backs look good. They have way less weight on them. I was thinking that 40 was a good # for the fronts but may try the 45PSI and see. Thanks.
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1971 LWB Custom, 6.0LS & 4L80E, Speedhut.com GPS speedometer & gauges with A/C. 20" Boss 338's Grey wheels 4 wheel disc brakes. My Driver
Seeing the USA in a 71


Upstate SC GM Truck Club
2013,14 and 2016 Hot Rod Pour Tour


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Get out and drive the truck this summer and have some fun!
It sucks not being able to hear!

LWB trucks rule, if you don't think so measure your SWB!
After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.
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Old 10-22-2011, 11:32 PM   #4
Longhorn Man
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Re: Air Pressures

a tire that is the correct width for the rim will generally be good at max pressure. I pretty much always run mine at max and as long as the width is correct, I've never had problems with wear due to inflation issues. This will also reduce rolling resistance (better MPG), makes handeling better from lack of sidewall flex and 'squirming' and keeps heat buildup to a minimum.
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Old 10-22-2011, 11:41 PM   #5
69heavychevy
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Re: Air Pressures

when i had low profile tires i would run them 5 psi under the max rating
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Old 10-23-2011, 12:03 AM   #6
project 67 sub
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Re: Air Pressures

i run mine right at the max pressure (i think its somewhere between 50-55 psi) with a 255/35zr20 tire, and a 20x8.5" rim
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Old 10-23-2011, 09:49 AM   #7
Andy4639
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Question Re: Air Pressures

The fronts are 20" x 8.5"

Backs are 20"x10".

So I should run at least 45PSI in all 4 tires then is what everyone thinks. Right?
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1971 LWB Custom, 6.0LS & 4L80E, Speedhut.com GPS speedometer & gauges with A/C. 20" Boss 338's Grey wheels 4 wheel disc brakes. My Driver
Seeing the USA in a 71


Upstate SC GM Truck Club
2013,14 and 2016 Hot Rod Pour Tour


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Get out and drive the truck this summer and have some fun!
It sucks not being able to hear!

LWB trucks rule, if you don't think so measure your SWB!
After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.
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Old 10-23-2011, 12:43 PM   #8
cdowns
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Re: Air Pressures

i have from the factory lo profile 45 tires on my daily driver the max reading is 51lbs on the tires/ the factory recomends 32lb of pressure

when running radials there is supposed to be sidewall flex that is the main advantage of radials over old biasply type tires

i think 45lbs is ALOT with no real aadvantage and a great posibility of giving up traction and adhesion
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Old 10-23-2011, 06:08 PM   #9
Andy4639
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Wink Re: Air Pressures

Well as of now I have 40 in the front and 35 in the rear. Haven't drove it yet but I will tomorrow to work.
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1971 LWB Custom, 6.0LS & 4L80E, Speedhut.com GPS speedometer & gauges with A/C. 20" Boss 338's Grey wheels 4 wheel disc brakes. My Driver
Seeing the USA in a 71


Upstate SC GM Truck Club
2013,14 and 2016 Hot Rod Pour Tour


http://upstategmtrucks.com/



Get out and drive the truck this summer and have some fun!
It sucks not being able to hear!

LWB trucks rule, if you don't think so measure your SWB!
After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.
Andy4639 is offline   Reply With Quote
Old 10-23-2011, 06:50 PM   #10
Longhorn Man
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Re: Air Pressures

When I was talking side wall flex, I ment where it squirms from side to side, like the sway from an over loaded trailer.
The absolute best way is to drive it at x PSI and after 10 or so miles of freeway speeds, take the temperature of the tread clear across the width. A durometer is best, a non contact lazer thermometer is great... but your hand will also tell you. Just run your bare hand across the tread and see if the center is hotter than the edges. This was you don't discover the tire is over/under inflated by tread wear (once it is too late)
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Old 10-23-2011, 07:43 PM   #11
piecesparts
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Re: Air Pressures

Everyone for their own thoughts on this, but the marking on the tire is the "MAX" recommended pressure. It is also tied to the load rating that is on the tire. I would go with the fact that you want a comfortable ride and decent tire mileage, so approach it with the thought that any tire should be pressed up to a point where the tire is making a good contact patch on the ground and not over or under inflated. I have 20" tires on my new truck and the factory has marked on the door frame to run the tires at 35 to 38 PSI, with the front slightly lower than the rear (where all of the load is carried). That is also the same as the tires on my wifes, Pontiac G8 (19" tires). If you choose to run at a higher pressure, then you will undoubtedly see a wearing of the centers of the tires and if under inflated, the outside edge. I have always run my tires on my vehicles at 35 to 39 PSI, with a good amount of highway mileage out of them.
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Old 10-23-2011, 07:56 PM   #12
cdowns
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Re: Air Pressures

a great starting point i think would b to go to a chevy dealer look in the lot for a new siilverado with 20" wheels and see what they recomend from the factory// in spite of the difference in years the specs are still pretty much the same
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