Community Forums

chickie · 07-11-2009, 12:21 PM

Just got our new F350 about 2 weeks ago. Can anyone tell me what pressures they are running in the duals when they tow? I used to put 80 psi in my old 350 SWR whenever I towed our 36' 5er. Now I still have the same pin weight but have 2 more tires to carry the weight and I don't think I will need the full 80 psi. Comments?

twalton · 07-11-2009, 12:58 PM

Hi Chickie,

Is your toy hauler an 5th wheel or a tag along? At any rate if you can get the rear axle weight with the the rig attached you can go to the tire manufactures website and get the recommended pressure for your situation.

ParTheCourse · 07-11-2009, 03:06 PM

Congrats Den, decided on a small one I see? Does it have the 110#, G’s?

I think the above is the best way to go, get underway weights at a CAT scale and refer to manufacturer charts but I still have not figured out an easy way the get air into them yet.

chickie · 07-11-2009, 07:21 PM

Mike it has the E rated tires, I did get it licensed for GCW of 26000 lbs. I was looking for a 450 but no one had one in 4x2 so they found this nicely equipped XLT 4x4 with 4.30 LS rear.I get my hitch installed on Monday then we go to Erie on the 23 of July. My pin weight was 2000 lbs if I remember right . This was taken at the National rally with the trike inside.

RustyJC · 07-11-2009, 07:30 PM

On my Dodge dually, I can handle the rear axle's GAWR at tire pressures well below the maximum 80 psig of the E-rated tires. Your tire pressure sticker in the driver's door should give you the tire pressures needed to achieve your truck's GAWRs.

Since you had your rig weighed at the National Rally, the optimum approach would be to take your truck's loaded front and rear axle weights and go to your tire manufacturer's weight and inflation chart.

Rusty

woodburner · 07-12-2009, 01:07 PM

I believe on my 2005 the front is supposed to be set at 75 and the dual rear at 65lbs.
I run the rear at 70lbs. when hooked up and the front are the recommended 75.
Tire wear and performance has been excellent.
BUT: I do think it a good idea to follow what the other posters have recommended.

glennwest · 07-19-2009, 04:18 PM

I have 245x85 on my GMC dually. I run all my tires at 80 psi. This is the maxium air pressure rating on tire. I tried 65 and they bulged rater well. Look much better at 80 with my 5th wheeler. When stopping for fuel I run my hand over all the tires, truck and rv. If all are about the same temp I'm satified. Heat is what kills tires and with all the weight of a 5th wheel i believe if temps are in check air pressure should be adequate. Works for me so far.

Ray,IN · 07-25-2009, 06:06 AM

chicke I have found out the hard way, rotate your tires as recommended in the owners manual. I didn't and the fronts washboarded. This cannot be corrected after the fact. When I did rotate the tires, those washboarded tires still create a vibration in the truck from their rear position. Tire shop says it will never go away until the tires are replaced. Cause? They said it's a 4WD thing.

FFStreetDoc · 07-30-2009, 12:55 PM

I too have an F-350 dually, put new tires on it shortly after purchasing it (used) ran them at 80 psi and wore the centers out in like 25,000 miles, the next set i ran at 45 psi unloaded, i run at 70 psi towing, 1,500 lbs tongue weight on the fiver, they seem to wear much better, no heat issues...