2005 2 wheel drive, quad cab short bed Michelin LT265/R 17 Tire pressure question.

[johnward]

Hi folks,

i just put a set of Michelin Defender LT265/70/R17 on my 2005 Ram Quad Cab short bed and I am looking for tire
pressure recommendations from folks that have put some miles on them with good results. I mainly run pretty hard but empty.

i previously ran 70 psi in the fronts and 55 psi in the rear when empty on Michelin LTX M/S2 and had really poor outer edge wear on the fronts. Front end alignments and regular rotations did not fix the issue.

The factory recommended pressure of Front: 50 PSI and rear 70 PSI does not make a lot of sense to me if you are not towing or loaded.

Any advise will certainly be appreciated.

 

[MichaelOverfield]

Hi folks,

i just put a set of Michelin Defender LT265/70/R17 on my 2005 Ram Quad Cab short bed and I am looking for tire
pressure recommendations from folks that have put some miles on them with good results. I mainly run pretty hard but empty.

i previously ran 70 psi in the fronts and 55 psi in the rear when empty on Michelin LTX M/S2 and had really poor outer edge wear on the fronts. Front end alignments and regular rotations did not fix the issue.

The factory recommended pressure of Front: 50 PSI and rear 70 PSI does not make a lot of sense to me if you are not towing or loaded.

Any advise will certainly be appreciated.

You will get many and varied opinions on this. On all my vehicles I go with the pressure on the actual tire. I've never had unusual wear issues, except crappy OEM trailer ST bias ply tires. Lower than tire rated pressure does nothing for the tire, it provides a softer ride, that is all, and it DOES lower your MPG. Now wait for others with differing opinions.. they will come.

 

[Killer223]

The amount it lowers the MPG might not be noticeable. but it doesn't hurt to try does it?
i run 50F 45R, average 18 highway, and 14 town on my early 04.
My 08 same pressures is maybe 1/2 mpg better on a good tank.

 

[MichaelOverfield]

The amount it lowers the MPG might not be noticeable. but it doesn't hurt to try does it?
i run 50F 45R, average 18 highway, and 14 town on my early 04.
My 08 same pressures is maybe 1/2 mpg better on a good tank.

It's a personal preference. I don't care for the slightly smoother ride, any of my vehicles.. so for me it's not worth any reduced MPG, and OP noted uneven wear, on OUTER edges, that is characteristic of under inflated tires. It the tire was designed for a certain PSI, that is what I use. It's never failed me. Mythbusters has done testing on many MPH boosting methods, and confirmed tire pressure helps improve MPG. Even if you go from 18 to 18.5 MPG thats a pretty significant % if you do the math, over a long trip that is noticable.

 

[DaveHess]

I use a racers trick for initial setting up of my drag slicks. After noting the starting tire pressure, take a piece of chalk and make a line across the tread. Drive straight for about 1/4 mile and see where the chalk is worn off. Outside edges of chalk gone, raise pressure and retest. Center chalk gone, lower pressure and retest and so on until the chalk is evenly worn off. Then I would know if I need to go up or down with pressure. For a drag slick, this is for an initial setting. I too have the Michelin LTX's on mine and they too are wearing on the edges on the front and I have recently had the front re-aligned. I run 60 PSI in the fronts and 70 PSI in the rears during towing season. This IAW a chart I found back in 2003 that listed all Dodge trucks (1500, 2500, 3500), tires sizes for each, and gave loaded and unloaded pressures for the fronts and rears. The rears I am going to leave alone on mine since I am towing but the fronts I am at least going to try the chalk technique and see what happens. Can't hurt. Just my 2 cents.

 

[6speed]

Of course the fronts will wear on the outer edges, they are steer tires, I have fleet of 3/4 ton trucks (65) and you would not believe the how fast the fronts wear out. I try to keep them rotated but some get away from before I can. Look in the door jam for the tires pressures and you can't go wrong. With all the trucks that I manage this gives me the best results. Of course I have 65 different drivers. But its works best for me.

 

[SnoKing]

If only the out edge of the front are wearing out(1 side, not on the inside also), then you have to much toe in. On 4 gens factory specs are 1/4" Cummins12V98 claims 1/16" works a lot better. SnoKing

 

[Tuesdak]

Weigh the truck on a CAT scale and then run the PSI recommended by the tire manufacturer for the weight. Their website should have a chart. Over inflated like unloaded rear tires at the door sticker PSI will wear the center of the tire out. Change tire pressures for loaded operation like towing.

Have you checked front end wear like the upper and lower bushings and ball joints? Sway bar end links? Condition of shocks?
My shop recommends the upper bushings done first as they fail faster than the lowers.

For a 2WD I like to run the "commercial" tires like the XPS rib or my personal favorite of Cooper's Discoverer HT3 as they wear more evenly vs. anything else. (IMO Michelin is too green and squirmy/soft handling of a tire for my liking. Esp. when one likes to corner fast and lean on the outer edge of a tire.)

 

[GrantP]

I use a racers trick for initial setting up of my drag slicks. After noting the starting tire pressure, take a piece of chalk and make a line across the tread. Drive straight for about 1/4 mile and see where the chalk is worn off. Outside edges of chalk gone, raise pressure and retest. Center chalk gone, lower pressure and retest and so on until the chalk is evenly worn off. Then I would know if I need to go up or down with pressure.

Totally agree with this!

 

[johnward]

Thank you all for your great advise. I am going to the scales and then use the chalk method to try and fine tune it.

 

[Bob4x4]

pay attention to hard hard you corner.You might even want to put another driver behind the wheel and watch how hard the tires work when doing tight turns.The newer Michelins do not perform like they did 10 years ago

 

[DaveHess]

John, Please keep in mind, I use the chalk method to get the best tire contact patch. It doesn't take into account any load requirements. I hope this helps you.

Dave