TIRE PRESSURE

[BrentMW]

I've heard so much talk about how important correct tire pressure is since the Firestone recall. The tag on my door tells me what the max. pressure for the front and back are. The tire MFG says something else, and a friend recommends yet another pressure for the front and rear.
What the heck is the correct tire pressure for my truck?

2001 2500 QC, 4x4, LB, Auto

 

[BHORNER]

Find a truck scales and get your truck weighed, The scales should tell you your front, rear & combined weights. then look at the rating on your tires. (Should be something like 3042 @ 80 psi for singles and different # for duals)

Use the 80 on the door for this to work.
Take your axle weight and divide it by the # of tires you have; then divide the per tire weight by the rating and multiply that by the max tire pressure (80 psi).
For example, my 2500's rear axle weighs 3,300 lbs and my tires are each rated at 3042 lbs @ 80 psi. To calc the tire pressure; (1650/3042) x 80 psi = 43. 4 psi. The front axle weighs 4,300 lbs, so the tire press is (2150/3042) x 80 psi = 56. 5 psi.

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Barry Horner
Lake Forest
Orange County, Ca

2001, SLT+, ETH, 6 speed, White quad cab, short bed, Sport, 2wd , 3:54 anti spin, Camper Special with trailer tow, 16x8 Forged Aluminum with 265x75 tires, Fog lights, Audio controls steering wheel mounted, AM/FM cassette with CD, Travel Convenience group, Keyless entry with remote, Leather agate heated seats. Line-X bed liner. ARE LS 2 tonneau cover. Pillar mount boost and EGT. EDGE EZ and McLeod clutch.

 

[Bumble]

Keep in mind, the pressure listed on the door frame may not cover after market tires. If your carrying a load, running after market tires, and your unsure which to use, I'd go by what's on the tires.

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2001, 3500, 5sp, 3. 54LS, 4x4, pyro and boost on the A-pillar, 165 watt backup lights, Thomas powered on-board air system, Grovers.

 

[Okie-Go]

I have 60 in all of them. I also have 66 gallon aux. tank. Tires wearing fine and ride is good. Of course if I get loaded I air up the rear tires.

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2001 quadcab slt 2500 HO 6spd. LWB,2wd,dk garnett red, trailer tow package,camper special, anti spin 3. 54 axle, speed liner,oversized stainless steel chicken slide,66 gallon in bed aux. tank,K&N air filter,Reese 20k hitch, Terry 2000 EX 30ft. double slide 5er, 2000 20ft gooseneck for haulin jeep, firewood and huntin stuff. 5X12 tagalong for haulin the 4 wheeler. Okie Newton

 

[illflem]

I've found for the best ride empty,in most conditions,with my reg cab 4x4 that 55 in front and 45 in the rear works best.

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95' 25004X4,AT,Driftwood,Banks Stinger,Warn fender flairs and running boards(work truck)
95 3500,5 speed 3:54,BD E-brake,Driftwood,Banks&Psycotty,34,000 GCVW apple and tractor hauler(works harder truck)

 

[Dane]

Remember - The tire pressure that works unloaded will cause the truck to wander all over the road when loaded heavy. When I returned to the pavement on my Baja trip, I had dropped the tire pressure to 35 lbs off road. My crappy 12vdc air pump was taking forever to fill the tires back to 70lbs. I gave up at 45 front and 35 rear and got back on the pavement. The truck was all over the place till I got to a fuel/air stop and put 70lbs in all 4 tires. It felt like a different truck after that.

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2001 HO 6 speed Regular Cab SLT 4x4 3. 54 anti spin 2500. Used for the daily grind and sneaking away to some secret Baja beaches toting a cabover

 

[TowPro]

I used to run 50 front, 45 rear, until I ran the centers of the Badyear RT's off. then I started to lower the pressure until I found 30 in the rear and the badyears would wear flat (but still real fast)

then I switched to Cooper SRMII's.
50 front, 35 rear (empty) and they wear great! 40,000 miles on them and they still look near new! (and its never been aligned)

When towing my 5th, I run 75/80 in the rear, and 50 in front.


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• 98 ISB,QC,5spd,2wd,3:54lsd. Stock with BD brake and Gauges!
• 2000 Terry 305G 5th wheel

 

[Fireman Dave]

I run the same as illflem. There was a tire pressure chart with my owner's manual. It gives different pressures for different options on the truck as well as loaded and unloaded. My truck steering wanders with too much air. After following the chart, it steers great.

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2001 2500; SLT; 4x4; QC; LWB; Auto; 3. 54 LS; 265s; Camper; Tow; Sliding Rear Window; Travel Convenience Group; Cab Clearance Lamps; Forest Green

 

[Banshe]

I run the same as TowPro. Found that the centers on the rear were just wearing out to fast. Found the center of the rear tires at 2/32 (to the wear bar) and the outer edges were at 7/32, as were the front tires. When I tow, then I push it up to max cold pressure setting. What I've seen with my truck, is the two major points for getting good wear are 1. Lower rear tire pressure when empty and 2. Rotate your tires religiously. This presupposes that you keep them balanced and aligned.

 

[Big-D]

Rotating your tires every 5000 miles regardless of type driving (loaded or towing) will provide max tire life. Proper tire pressure goes hand in hand with rotating. Dave

 

[Dave MacArthur]

I weighed my truck and then called Michelin. They gave me a list of pressures to run at different axle weights. Empty I am running 55 in front and 42 in the rear. I have 45K on them now and they will make it another 5k easily (OEM tires). I think that calling the tire manufacturer and getting a chart for various axle weights is the best choice.

Dave

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99 QC SB 4x4 Auto
Factory Ordered
Most Options

[This message has been edited by Dave MacArthur (edited 02-08-2001). ]

 

[madams]

Im with illflem & firedave . . 55fronts 45 rears.

I ran max front and rear for a while until I applied the above formula that BHORNERIS
posted. Almost wore the rears out . . caught it just in time.

I was a little leary about the 45 in the rear . . but it works well. Just enough air for the depot runs and city driving. If Im on the road unloaded and 70 mph . . I bump the rear presure to 50.

This applies to my michelin 245 75r/16's. Apply the formula for your tire spec's

Good luck
Michael

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00 Driftwood 2500 ST QC ISB LB 5spd 3:54 LSD Tow & Camper Groups . . SunnyBrook 33FKS Travel Trailer

my photos

 

[RKohn]

55/45 here too. Dang michelins won't wear out, 42k and a lot to go.

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Y2K Red Stealth Sport 2500 4X4 QC SLT+, 5-spd, 3. 54 anti-spin, 265-75-16 LTX’s (There ain’t no such thing as options, cause ya gotta have it all, including: DC’s dead cow/vinyl interior and don’t stop anti-lock brakes. ) Stock, but not for long. Oops, too late. What silencer ring? (More fun than my 98 SST)

 

[Koa Man]

Since I am almost always hauling something, I always run the max. pressure stated on the tire for the rears, little less in the front. On my Dodge, it is 80 rears, 70 fronts.

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1996 3500 Clubcab SLT, auto, 4. 10 limited-slip, TST #5, 370s, AFC spring kit, Psychotty, Dunrite converter, Trans-Go, DiPricol EGT, boost & trans temp. gauges, 9 ft. aluminum flatbed and tool boxes with Venco dump. Custom front bumper, Hadley air horn, PowerVision mirrors & 4" Stack Exhaust.

 

[Evan A. Beck]

I run 60# on an all 4 corners. I like the higher pressure because it gives slightly better fuel economy. More tires pressure = less rolling resistance. It breaks down like this: The less pressure you are running, the less round the tire will be. That is, it'll be "squished" more under the weight of the truck. This in turn creates more rolling resistance. With a higher pressure, the tires don't have as much of a tendency to be "sqished" under the weight of the beast. I noticed about . 4-. 5 MPG difference when going from 50/45 to 60/60.

It's worth experimenting! Only sacrifice with the higher pressure is a little bit rougher ride. But hey, it's a 1-ton suspension, it is supposed to ride a little rough! #ad

 

[nascar]

I run 45 front and 40 rear empty.
Rotated @ 6K miles as shown in owner's manual. No goofy wear pattern showing.


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2001 QC, 2500, 4X4, H. O. CUMMINS, 6SPD, SPORT, LB, SLT+, 3. 54 LSD, CAMPER PKG, TRAILER TOW, CAMEL/TAN, FLAME RED!
Westin Step Bars #26-1240, Pendaliner SR, Mopar Molded Mudflaps, Driver/Passenger Door Glass Tinted 20%

 

[groundpounder]

I run mine loaded alot as well. I keep 80psi in all four. I still have the factory Mich ltx's on my beast 35k and alot of tire still left. A little rough when mt but nothing I can't live with. I think the key is ROTATION ROTATION ROTATION!!!

 

[Missouri Mule]

I run mine at front 70 and back 80. I never know when I 'll put a load in the back or be high speed driving on the highway.
the correct tire pressure will help keep your tread from flying off.
Of course if your using a Load Range D tire you can't run the manufactures recommended air pressure.

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Bill Thomas
Missouri Mule - 96 Wht 4X4 ST CC,5 spd, 3. 54, 8 ft bed, 1 ft high cheater boards.
99 Freightliner bl/wht FL60 ISB-5. 9 24v,215 hp,520 tq,6 spd, 3. 59 nsr,16 ft box, 19. 5 tires,Wt/gvw 11,000/23000

 

[GeoVeo]

I had been running 50F/45R empty but was wearing faster in the center. Have dropped to 45F/40R for the last 25K, ride is smooth and not squirly. Run mostly empty but do some car hauling, then bump them up about 10lbs.

I rotate every 5-7K, last weekend it was time and tires showed 8/32 center, 10/32 on the edges with 73K on these GoodYear APT LT 265/75/16C which were 17/32 new. I'm pretty happy with the results.

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'94 2500 Driftwood, Auto 4X4, 4. 10

 

[KCJackson]

For stock size tires and load ratings, these are the best charts I've seen:
http://www.trucktires.com/Loadinfl/table13.htm

This is from the Bridgestone/Firestone commercial truck tire site. I found this chart while looking over the Bridgestone M773 tire, and ended up buying 6 of them for my 3500. Following the load rating chart, I placed the pressure for where I expected my load to be, and while the front tires will probably not make it through the spring (2 years old), the rear tires show almost no treadwear - still have most of the original siping.

By the way, I run 70 front, and 40 across the 4 rears (light loading in the bed most of the time).

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1996 3500 Club 4x4 Laramie SLT, unmodified 180/420 12-valve, 47RE automatic, 3. 54 limited slip

[This message has been edited by KCJackson (edited 02-13-2001). ]