Tire Pressure Question

[Archive]

I will soon be putting michelin 265 or 275 tires on my 2500. I run empty 95 % of the time. What are the front and rear pressures I should use to get the best wear and ride out of these tires. These tires have a max pressure of 80 psi. My driving is all highway.

Thanks
Ken

------------------
1998 1/2 24 valve 2500 automatic 3. 55

 

[Archive]

I'm running 55 front and 45 rear on Michelin M/S 265s with good results. A bit soft in the faster turns but smoother in the slower stuff. Wear seems even so far. Loaded pressures are 70f and 65r with the 1800lb cabover

------------------
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

 

[Archive]

10 psi higher on the fronts is a good rule of thumb. 55/45 may be a little low if you are driving 70+ mph a lot.

 

[Archive]

I've been running mine 55/55, because I balance them frequently enough that I don't have to worry about adjusting the air pressure (I do monitor it frequently though) and I don't notice the ride being any different with more air pressure in the rears. It's already stiff and rough in the back end, the extra 10 psi made no difference to me.

------------------
Y2K 2500 Cummins ETC/DEE, SLT+, 4X4, Quad, LB, Intense Blue Sport, 3. 54 anti-spin, rear aux. springs (camper special), sliding rear window, all options except cab clearance lights including agate leather, totally stock, some ring fell off, whistles louder since & D/C must have screwed up on the wiring cause the fogs stay on with high beam. Since everybody else listed their toys, I will too.
1995 Kawasaki ZX6-R (For Sale)
1990 Toyota Celica
1983 Mazda RX-7 GSL (For sale)

 

[Archive]

Ken try this. It works.

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)
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.

------------------
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 soon to come McLeod clutch.

 

[Archive]

I run mine at 62/52 this works good for me.

------------------
Eric Pitts Terre Haute Indiana
2001 Properly Valved 2500 Qcab 4X4 auto Transgo shifts it 4. 10 LSD Prime-Loc Weston Nerf Bars Smith built brush guard Command Remote Starter Scotty Air DD stage 1’s, boost fooler, elbow 32psi boost 247hp,657tq Neophyte B. O. M. B. er
The Pitts Home Page
Member GLTDR

 

[Archive]

Originally posted by Ken Tenpenny:
I will soon be putting michelin 265 or 275 tires on my 2500. I run empty 95 % of the time. What are the front and rear pressures I should use to get the best wear and ride out of these tires. These tires have a max pressure of 80 psi. My driving is all highway.

Thanks
Ken

Ken... I am running 46 front and 40 rear with Mich M/S 265's. This is the rating given by the product guide that was in my new truck. It takes into account tire size, 2wd/4wd, 1500/2500/3500, duelly/not.

thats all I have to go on except that when it sits on the road the tires look good (equal, a bit relaxed, not stiff). When I got the truck new from the dealer all 4 were pumped over 60psi and it had no traction at all off road.

------------------
2001. 5, QC, 2500, 2wd, auto, 3. 54, 4 disc, long-bed, all the stuff, heated leather, patriot blue over silver, stock4now!

a real "country cadilac"

 

[Archive]

I am running 255/85R16 and I used a clean floor to get full contact of the rear tires. I run 60 in front and 40 in rear.

 

[Archive]

No where even close to being knowledgable on this topic . . but I was considering the move to 265's . . but was warned that the final ratio would be something in the 3. 2 range which could possably effect my performance when towing.

Thought I'd pass that on . . see what others here have to say.

Oh . . I use the numbers / equation BHORNERIS listed, as a guide to get me close . . I run 55 front 45 rear unloaded, pump the rears up to 80 when I tow. 15K and no unusual wear patterns.

------------------
00 Driftwood 2500 ST QC ISB LB 5spd 3:54 LSD Tow & Camper Groups

my photos

[This message has been edited by madams (edited 11-14-2000). ]

 

[Archive]

I have Goodyear Wrangler AT/Ss on mine and I'm running 42 up front and 35 in the rear. They're different than the Michelins and I know you can't give them as high of a pressure, but you generally want about 10psi less in the rears.

------------------
Chris Timochko
1997 5sp 4X4, HX40, BD 4" Brake, Marine Compression, Custom Tuned Injection Pump, 370B Injection Nozzles, Delivery Valves, Governor & AFC Spring Kit, Psychotty Air, Water Injection, NOS Diesel Kit, 6" Chrome Exhaust System, No Smoke Valet Switch, McLeod Dual Disc Clutch, Mag-Hytec Rear Cover, Cummins Chrome Kit, Optima Red Tops, Hadley Bully Horns, Hurst Line Loc, Goodyear Wrangler AT/S 305/70/16s. Test mule for Auto Wurks Diesel race program

 

[Archive]

Hey BHORNERIS, where'd you get that calculation? Sounds pretty good to me, but I'm just wondering if you made it up or if you found it in some tire information source?

 

[Archive]

I have 265s, for the first time the speedo reads correctly (at least at 70mph).

With the 3. 73 it is already a huge range between gears, but no noticable difference from the smaller tires. Still at 80mph it is running at around 2200 RPM. I could easily use half of a gear to get it down around 1800is.

Bottom line, delay shifts, but at 50 mph the rpm is in its power range from then on.

------------------
'96 4x4, 2500 extended, 5-Stick, TST, big stereo, MP3 player, GPS, Kodiak Sidewinder steps.

http://www.geocities.com/mr_bubba_zanetti/

 

[Archive]

Run 60 psi all the way around on both trucks.

------------------
1998 4x4 2500. White. Regular cab. Not bombed. Gear Vendor(9 forwards)
2001 4x4 3500 White Flat bed. Has BD Plug in Power.

 

[Archive]

Bubba,
3. 73's?Did you change gears?


Rick

------------------
99 3500 4x4 QC,5spd,3. 55 posi,turn over ball goose neck hitch,Putnam class V reciever hitch,Alcoa alum. wheels,275 hp inj. home built boost module,4 in. straight exhaust(built it in my shop)Pac brake,4 leaf overload springs,all options execpt leather & keyless entry,2000 Artic Fox 10 ft. camper,with slide out 2horse tongue pull trlr. ,30 ft. gooseneck 3 horse living quarter trlr. ,24 ft flat bed that I haul my 6200# modified alcohol burning Ford 4x4
pull truck on.

 

[Archive]

I've been running 50psi in the fronts and 40psi in the rears with the original Goodyears. They are almost worn out and I can see that the tread in the middle is more worn than the outside edges. Indicates pressure has been too high but I'm still going to get about 60,000 miles out of them.

------------------
1996 Dodge 2500 4X4 SC, SLT, Cummins 12V, 5-spd. , JRE 4" exhaust (my kitty ran away into the woods and the muffler fell off!), TST 280 HP/685 Ft-Lb Uprate Kit, AFC Spring Kit, Horton Fan Clutch, Jacobs/Ram Exhaust Brake, MagHytec Differential Cover, Prime-Loc, Rancho RS9000 Shocks, Combo Gauge, K&N Air Filter, Brite-Box, Geno's finger-touch oil pan drain plug, no turbo silencer ring, full-time fog lights.

 

[Archive]

run 70 psi front and rear. Truck rides real well, and they run nice and cool. If you have a 4x4 then the preasures should at least all be the same, the front may need about 10 psi more

------------------
http://www.mudrunner.sites.cc

 

[Archive]

If your running highway follow Dodges recomendations 65 front 80 back. Keeping tires filled will keep them cool(not over heated) running highway.
Read Greg Whale's column in issue 30.
LT tires are not made for high speed runs.
I know we do it any way. #ad

If tires get overheated tread will start to seperate.

 

[Archive]

JyRo

I don't remember where I got the formula. I have had it in my archives for some time. If you look at it closely it makes perfect sense. Try it if you want or use some other logic. I do hear lots of opinions, but no stats. to back them up.

------------------
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 soon to come McLeod clutch.

 

[Archive]

I posted this formula a few months back for someone else who was asking the same question . I picked up this trick from Four Wheeler magazine many years back when they had dedicated the issue to wheels and tires. I've been using it since with great results. Glad I'm not the only one who remembers it.

------------------
y2k 2500 QC SLT+
3. 54, Automatic, Rhino Liner, every option except camper

 

[Archive]

On mine I run regular inflation in the front and 5-10 lbs less in the rear unloaded and regular inflation lodaded.
The Choice is yours but I would not suggest running over 10 lbs under on the front if you do any hwy driving due to tire heatup. which leads to seperation (pord and Firestone is finaly figuring it out).
Also watch wear and rotate.

Mac

------------------
95 Ram 2500 Auto Std Cab, Cat & Muffler Fell off, 125,000 miles.
Bombed-to-be!