Tread wear outer dually tires on F350 - Diesel Forum

brucebr · 08-28-2009, 09:18 PM

Never seen this discussed before. I have 39,000 miles on my 07 F350 dually diesel Tow Boss. I'm the original owner. I've pulled a 15,000 pound fifth wheel for maybe 10,000 of those miles, keeping my weight 1,000 pounds below the truck GCWR.

I just checked the tires (Continental LT245/75R17all around). The middle of the tread of the outer dually tires are worn down, just about even with the wear bars. Inside tires look just fine, as well as the front tires.

I monitor my tires frequently, particularly since I have Pressure Pro sensors on all truck and trailer wheels. 75F/60R towing, 60F/45R not towing. I keep the same pressure on all four dually tires. Don’t drive hard anymore like I usta.

The outer tires wear pattern indicates overinflation. Should I have maintained lower pressure in the outer of the dually tires when towing of not? Or has someone been following me around with sandpaper, sanding down the middle tread, and he's too lazy to reach in to the inside tires?

Now I need to find two used LT245/75R17, so I don't need to replace four or even six tires.

Your thoughts??

Bigshow · 08-29-2009, 11:09 PM

You made about one quarter of your miles towing. A few questions >> did you rotate the tires at all ... and what air pressures were you running empty and loaded???

brucebr · 08-30-2009, 12:21 AM

Mr Show,
Thanks for the reply.

I've never rotated the tires.

Tire pressure = 75F/60R towing, 60F/45R not towing, confirmed with a digital pressure gauge. I monitor my tires frequently, particularly since I have Pressure Pro sensors on all truck and trailer wheels.

I determined my unloaded pressures with the old chalk test, i.e. putting a stripe of chalk across each tire and looking at wear at different pressures. Loaded pressure I took from the tire manufacturer's label on tire pressures.

I could think that one of the rear sensors is wrong. But the wear pattern is the same left and right. Same question and answer for a bad rim.

I was wondering if the outer tires wear differently in turns than the inner ones. But then this would be a common problem in DRW trucks.

Bigshow · 08-30-2009, 11:46 PM

I had a 2003 F350 DRW and got 155000 kms out of a set of Michelins but I rotated them a few times, including the full wheel/rim dismount for the fronts because of the aluminum rims. I am curious about the outside ones wearing more than the inside ones myself too! I think I ran lower pressures in mine both empty and loaded based on the information I found from the tire makers for tire size/load/psi charts. Mine had 235/85/16 for tire size.
I wish I could help, but do keep us informed as I am now wondering about this.

brucebr · 09-01-2009, 09:03 PM

Just talked with the Ford dealer. Who says that the outer dually tires will wear out faster if all are underinflated. Guess I'll bump the unloaded pressure down to 40 on my new

set.

Thanks all for your help.

RatherBNtheWoods · 09-01-2009, 09:20 PM

Quote:

Originally Posted by brucebr

Just talked with the Ford dealer. Who says that the outer dually tires will wear out faster if all are underinflated. Guess I'll bump the unloaded pressure down to 40 on my new

set.

Thanks all for your help.

The outer tires will wear more if all are under inflated(low pressure) so you're going to lower? the pressure? I don't get it.

I run placard pressure all the time because I never know when I may be loaded(overloaded) next. I get 60K ish miles on the fronts, and 80K ish miles on the rears without rotating because of FoMoCo's DA idea of not polishing both sides of the wheel!!

brucebr · 09-02-2009, 12:26 AM

Quote:

Originally Posted by RatherBNtheWoods

The outer tires will wear more if all are under inflated(low pressure) so you're going to lower? the pressure? I don't get it.

I run placard pressure all the time because I never know when I may be loaded(overloaded) next. I get 60K ish miles on the fronts, and 80K ish miles on the rears without rotating because of FoMoCo's DA idea of not polishing both sides of the wheel!!

Ooop. You right, I'm wrong. Meant to say that they are overinflated, i.e. middle treads worn and outer not worn. Thus my, and salesman's, thought to bump pressure down 5 pounds.

Yet you are the second person to suggest the same remedy. Use max pressure loaded and unloaded. Which surprises me. That you should use the same pressure with a difference of 3,000 pounds bed weight. I would think you would increase the pressure to maximum. But you, and this other guy, think not.

I'm certainly not questioning your experience. This is my first F350 and first dually. It's a puzzle to me, and an expensive one too.

RonRosewall · 09-02-2009, 07:15 PM

I am just now looking to replace my BFG rugged trails that came on the '06. I rotated them every 10k including remounting and balancing them and I got 68k on the original tires. I too run mine at 80 in the front and 70 in the rear all the time.

brucebr · 09-03-2009, 12:13 AM

Of course, I'm trying to fit this discussion to my situation. Since I usually tow my trailer someplace and leave it for a month or more, I run empty for set periods of time, and about 3/4 of my total driving time. So I can, and have, modified my pressures up and down for unloaded and loaded weight.

Mr. Woods runs full pressure cause his weights vary too much. Makes sense to me. What about you, RonR? Do you run loaded most of the time, so you keep your tires at max pressure?

Note that I vary my front tires too, according to load. And they, as well as those inner rears, are wearing just fine.

CZDiesel · 09-03-2009, 12:46 AM

I also recommend six way rotation. I got about 65K on my Goodyear Wrangler Silent Armors by keeping them rotated but yes they will wear the inside of the tread if you don't rotate. The Goodyears are rather aggressive and will cup a little in the front after 10 to 12k so this is when I usually rotated. I put 40k on my truck last year with about 25K pulling a 15k trailer fwiw

brucebr · 09-03-2009, 09:32 PM

Quote:

Originally Posted by CZDiesel

I also recommend six way rotation. I got about 65K on my Goodyear Wrangler Silent Armors by keeping them rotated but yes they will wear the inside of the tread if you don't rotate. The Goodyears are rather aggressive and will cup a little in the front after 10 to 12k so this is when I usually rotated. I put 40k on my truck last year with about 25K pulling a 15k trailer fwiw

Whazzat 6 way rotation cost ya?

CZDiesel · 09-04-2009, 01:58 AM

$60 at Costco

wingnut60 · 09-04-2009, 09:17 PM

CZDiesel--does your rotation include moving tires to different rims to keep the polished side out?

CZDiesel · 09-05-2009, 01:45 AM

Quote:

Originally Posted by wingnut60

CZDiesel--does your rotation include moving tires to different rims to keep the polished side out?

Yes, if you have bought your tires there then they give free rotation and balance but if you need dismounts then it is $10 a wheel.

brucebr · 09-05-2009, 05:30 PM

Well let's see

Rotating cost $10/tire = $60 for 60k miles.
Replacing the $200 tire at 40k means spending an extra $70 for the shorter mileage. It's a wash. Tho replacing two of the dually tires at this point may mean replacing four.

But free at Costco means saving that $70/per tire, which comes to buncha money. Even if you just figure extending the mileage of the 4 rear tires @$70. If you ever looked at my truck, you'd know I don't care so much about shiny.

(And actually, half the time you have the shiny side out anyway.)

So you've convinced me of the value of rotation. Couldn't get it for free this first go-round on a new truck. As a fulltime RVer, I've left my Tacoma dealer behind.

Still kinda wondering about this rear dually tire pressure question tho.... You guys think I can't avoid the uneven wear on DRW tires without rotation in any case?