2nd Gen Non-Engine/Transmission best tire air pressure for mileage/wear etc

[JCyrbok]

My truck (see sig line) has Toyo Open County AT's on it in the stock size. I have been running them at 70psi front and rear and get good mileage and I am used to the ride (or lack there of, LOL).



I run empty or very light 98% of the time. I noticed that my back tires are starting to wear in the middle more than the outside/inside (still very serviceable though). Fronts are fine with little wear.



They were last rotated about 10k miles ago ( i know, i know) and have about 38k miles total on them.



What PSI are you guys finding is giving you the best mileage/wear/ride combo when empty??



Thanks

J-

 

[Allnew2Me]

I have the same truck you do with the stock 265 size in the Michelins. According to my Dodge paperwork I should be running the fronts at 45 and the rears at 40. At these pressures they slightly wear on the outer edges which indicates underinflation but the ride is softer. The steering is also softer and less responsive at these lower pressures.

I have played around with the pressure going up to 60 in the front and 55 in the rear empty and found that this was too much in the sense that it rides really hard and the back end bounces more over the concrete-highway control joints.

If you run empty you don't need 70psi and as you know you will wear the centers out prematurely. I am now at 50/45 and they seem to wear evenly and the ride is okay also. My door sticker shows that for the full GVWR the tires should be 65/80 but that is with 245 tires.

If you consult the tire manufacturers chart they will tell you what the proper pressure is for the weight being carried, but you would have to weigh each corner and even then it may vary due to driving habits or vehicle/tire combinations.

I usually rotate at each oil change (5K) but I get a pretty good pull to the right with any other position, and I've tried them all, than what I have now so I don't rotate any more. I have them back where they run straight and as long as they are wearing evenly I will just leave them there.

 

[WestTN]

Allnew2me, those numbers sound like the pressures for a truck with no load at all.



My truck runs most of it's miles with no load and all tires ( Michelin 265's ) at 65 psi with NO excess wear in the middle. They are absolutely flat across across the tread. The original's ran over 90,000 miles and the only replacement set are on track to do the same. You may be cornering too agressively.

 

[Allnew2Me]

The 45/40 is the Dodge recommendation for an empty truck and i think they are alittle low for the weight of our trucks. I am higher than that but I never left them at the highest pressures long enough to see any wear patterns because the ride was too rough for me. I'm surprised that you don't have center wear at least on the rear tires with 65psi empty.

 

[WestTN]

The tires are steel belted radials. When mounted on the correct size rim, they will stay flat to the road.

 

[georgej]

My last set of Toyos woreout the middle of the tread first. I was told this is common with Toyos. Interestly the previous tires( goodyear) wore on the outside first (front 2wd). The toyos had much better traction and were smoother riding also and will be my replacement tires next time. .

 

[tempforce]

i'm still on the oem tires, 65 front, 55 rear. rotating every 10 k. tires not showing hardly any wear. apprx 30 k. on truck

 

[rjrkihap]

georgej,

Toyo M-55's (if that is what you have/had) actually have a hump/mound in the center section of the tread (starting and ending about 1/2inch from center) which, when measured with a tire gauge will show the center has less tread depth than the outsides. I was told this is to improve the tires overall structure and strength. I called Toyo and they confirmed that when the center is completely "bald" you still have 1/8 of wear left in the tires. So on the M-55's, even though they appear to wear quicker in the center, they are actually wearing normally and evenly.

Ron

 

[Midnite]

The basic inflation pressure is only part of the picture. Inflating a load range D tire to 45 psi is very different from inflating a load range E tire to only 45 psi. The Ds typically have a max sidewall pressure of 65 psi, and the Es are typically 80 psi max.

On my truck I always go to max sidewall pressure on all tires if I have my camper in the bed. Otherwise, if I'm empty I'll air down the rears a bit but leave the fronts at max.

Mike

 

[Joe Mc]

When I had stock tires on mine (265/80/16, E range) I found the best pressures to be, 65 front and 50 rear, keep in mind I never tow anything. It was suggested to me if I towed or had a heavy load in the bed to increase to 70 f and 80 r.

If you are noticing wear in the middle of the tread = psi too high, adversely tread wear on the outer edges = psi too low. A fellow TDR member made a suggestion - to find best psi make a chalk mark across the tread then roll the truck a few tire revolutions. Judge best pressure by the most even removal of chalk across the tread. Makes sense . . .

 

[Midnite]

If you are noticing wear in the middle of the tread = psi too high, adversely tread wear on the outer edges = psi too low.

In practice this doesn't really apply to the front tires on our trucks because the front end is so heavy with the Cummins. You can't inflate the tires up to the point where they lift the outside edges of the tread any amount--the tire will rupture before that happens. This is why I always inflate the fronts to max sidewall pressure. Naturally, the rears are going to be dependent upon whether you've got a load or not.



Mike

 

[kscheffler]

georgej,



Toyo M-55's (if that is what you have/had) actually have a hump/mound in the center section of the tread (starting and ending about 1/2inch from center) which, when measured with a tire gauge will show the center has less tread depth than the outsides. I was told this is to improve the tires overall structure and strength. I called Toyo and they confirmed that when the center is completely "bald" you still have 1/8 of wear left in the tires. So on the M-55's, even though they appear to wear quicker in the center, they are actually wearing normally and evenly.



Ron

I talked to Toyo about this same issue that I am seeing on my M55's. They told me that there is an additional layer laid down in the center section to provide better puncture resisatance. I have been running mine at 65 psi unloaded an now have 35k on my tires. They should make 50k no problems. But I find it hard to believe that the tire is going to provide good traction when the center area of the tire gets to the smooth condition.

 

[Bob Cochran]

I am wondering if I missed this if so forgive me. Has anyone weighed their truck and adjusted tire pressures accordingly? Certainly weight at each wheel be best but by axle will work. When I weighed my truck to determine air pressures with the 5er attached I also weighed the truck with out the 5er. Make sure the 5er and truck are loaded as you would be traveling. All fuel tanks full, you, wife, kids in truck, etc. Just a thought most people will find there trucks weigh different even to a seemingly the exact same truck of a friend. I don't put in the exact pressure indicated after weighing and calculating lazy I guess but close. My truck empty I am running 60 PSI front and 30 PSI each of the duals in the rear(easy to remember). Example the air pressure calculated for rear is under 30 PSI and I just don't like running tires that low unless it is off-road sand, etc. That is just me though!!!!!

 

[tempforce]

30 psi in your duallys may be a bit low. i'd keep 35 in them.

i keep 60 front, 55 rear unloaded. if i'm taking a long trip i use 65 front.

loaded i run 75 front and 80 rear. rotating every 10,000 miles.

 

[MVenditti]

Every vehicle load and tire combo is different. Years ago in a truck mag they showed a way to figure pressure for front and rear. For best wear,traction and breaking you want maximum even tire contact across the tread. The way they did it was on a flat surface where you can drive 100 feet or so. First chalk a straight line across the tires then drive straight a bit and check the chalk mark. if it wears in the middle your over inflated etc. add or remove couple pounds at a time till you get even wear on chalk line then record your pressures. you can do this with a load you usually carry to record those pressures also, pretty simple just some time to get right. Hope it helps.

 

[Bob Cochran]

30 psi in your duallys may be a bit low. i'd keep 35 in them.

i keep 60 front, 55 rear unloaded. if i'm taking a long trip i use 65 front.

loaded i run 75 front and 80 rear. rotating every 10,000 miles.

I have not seen any abnormal wear on the rears using 30 PSI I may increase to 35 just because. My reason for staying 30 or above is keeping the beads from popping of when cornering unloaded on highway mountain curves. Not to say i drive this like a sports car far from it LOL. When loaded with my 5er I run 65 front and 60 each tire in the dually. Actually front axle does not increase a lot weight wise with the 5er connected. Since I have Michelin XPS traction treads rear and highway rib front rotation is limited to side to side not front to rear. I have not seen wear that wouls show I need to rotate side to side.



Reason for traction treads is I have 2 mile of dirt road to negotiate to the highway. Mud and sometimes snow is reason for the traction's and all the help I can get or I break out the Jeep if it gets more than I think the truck can handle.

 

[Midnite]

Bob, what tires are you running, load range D, or E?

 

[Bob Cochran]

Bob, what tires are you running, load range D, or E?

Load range E