Rear tire pressure dually

[Obewan]

Just changed from a TT with 1200lb tongue weight to a fifth w approx 4000 pin weight. Haven't gotten to the scale yet. I'm confused.... placard on truck door says tires rated at 2660lbs at 65psi for rear duallies. Michelin load rating says 2778 at 80psi for duals. Should I inflate to 65or 80psi? Didn't have to think about this as much with only 1200lbs. Always kept it at 65.

[RustyJC]

I'm running 65 psig cold in the rear tires of my dually when towing the 5th wheel in my signature below. According to the TST 507 TPMS, pressures will increase and stabilize around 4 psig above cold inflation pressures at ambient temperatures of 90 degF or so, and tire temperatures increase about 6 to 7 degF above ambient temperatures, depending on road surfaces and which side of the rig gets direct sunlight. (An interesting observation - to me at least. The inside right rear tire is closest to the exhaust pipe, and it will run 5-8 degF hotter than any of the other 3 rear tires when making a long pull up a grade while towing.)

65 psig is the door sticker pressure recommendation for maximum rear GAWR. The E-rated tires are capable of 80 psig if needed.

Rusty

[donn0128]

I run 80 in all my tires. That way I dont have to worry about overloading the tires right up to the trucks max. In 30K miles I never noticed any undue tire wear.

[wandering1]

Follow what is on the tires, Michelin had a reason for putting that on the tires. What is on the door is wrong if it is not for the brand and size tires you have on the truck.

[SanMarMor]

If the door placard says 2660, which is 10640 total, at 65#, that's what I'd set them at. That is way more than you're carrying. At 80#, you will have a harsh ride, and wear the center of your tires out.

[JIMNLIN]

You may want a mod to move you over to the tow vehicle forum as this is the 5th wheel trailer forum.

As rhagfo says 80 psi is for carrying max 1110 lb rear axle loads which I doubt any 5th wheel trailer RVer ever will.

I've always ran my DRW trucks rear tires in the 55-65 psi range depending on the load. That way my tires don't bulge at the bottom enough to get hot at interstate speeds on a long all day trip.

[We_Cant_Wait]

Put your truck on a scale with the 5th wheel hooked up and see what your weights actually are. The go to the Michelin tire inflation chart and determine by your actual weight what your REAL tire pressure should be.

[Puddles]

The Mad Norsky wrote:

randeez2001 wrote:
I keep my front tires at 65psi and my rear tires at 80psi.

:h

I honestly think that is just backwards from where it should be.

Especially if you are running the diesel engine versions.

Those engines are HEAVY and front tires are always carrying that load.

Keep the front's aired up good. I had cupping and wear troubles on the front tires for my 2011 Ford dually cause I ran them like the dealer had them aired to, which was actually way too low.

Started running them at 75 PSI instead of the 55 PSI and wear/cupping troubles went away. Front tires here.

Back's at 65 should be fine.

X 2

[The_Mad_Norsky]

randeez2001 wrote:
I keep my front tires at 65psi and my rear tires at 80psi.

:h

I honestly think that is just backwards from where it should be.

Especially if you are running the diesel engine versions.

Those engines are HEAVY and front tires are always carrying that load.

Keep the front's aired up good. I had cupping and wear troubles on the front tires for my 2011 Ford dually cause I ran them like the dealer had them aired to, which was actually way too low.

Started running them at 75 PSI instead of the 55 PSI and wear/cupping troubles went away. Front tires here.

Back's at 65 should be fine.

[byronlj]

65 on all six for me. Improved ride and tread life.
Dave

[rhagfo]

Obewan wrote:
Just changed from a TT with 1200lb tongue weight to a fifth w approx 4000 pin weight. Haven't gotten to the scale yet. I'm confused.... placard on truck door says tires rated at 2660lbs at 65psi for rear duallies. Michelin load rating says 2778 at 80psi for duals. Should I inflate to 65or 80psi? Didn't have to think about this as much with only 1200lbs. Always kept it at 65.

Well if you inflate to 80 psi that is a total of 11,112# of capacity, do you need that much?

At 65 psi you have 10,640# of capacity, so hit the scale and get your loaded and unloaded weights, my guess is 65 psi is more than enough.

[Mile_High]

I can't run my rear tires at 80, or I lose the hubcaps. I lost three on the same bridge before I figured it out. Back to 65 as stated on the tires for dual tires, and I've kept my hubcaps for over a year driving the same bridge.

[christopherglen]

There should be a rating stamped into your rims, the lesser of the rims or tires is the limit.

[Greentow]

I stay at 80 all around on my Ram dually. 3100 pin weight.

[blkdodge]

X2

[randeez2001]

I keep my front tires at 65psi and my rear tires at 80psi.