Tire wear

[Tom_D]

We just got back from 5 weeks in Canada.

I was using front tires that had about 9000 miles on them and that seemed good at the start of the trip. After the 6000 mile trip the fronts are badly cupped across the tread. The truck has always pulled slightly to the right on some roads and over many miles this is probably the cause of the cupping.

The brakes are not dragging and I had the front end aligned last year and everything looks straight and tight. I have not weighed the corners. I run 76 psi in the front for highway driving.

Does anyone else have any front end pull or wear issues?

My plan is to replace the OEM Yokohama tires with Toyo M55's and to rotate the tires at every oil change (6000 miles).

Thanks
Tom

[Guinness44]

Have you checked into centramatics? We run them on all diesels. (Do I admit I have never rotated the tires on the frontheavy Ram, and 40Kmiles later, no cupping).

[Tom_D]

Thanks for the tip. I did go to the centramatics web site but it doesn't look like they make a product that will work with the FUSO's 16" 6 lug wheel. I am going to contact them directly and ask.

I am looking to see if I can find other wheel balancing systems.

Thanks
Tom

[762X39]

We just got back from 5 weeks in Canada.

I was using front tires that had about 9000 miles on them and that seemed good at the start of the trip. After the 6000 mile trip the fronts are badly cupped across the tread. The truck has always pulled slightly to the right on some roads and over many miles this is probably the cause of the cupping.
Thanks
Tom
My unimog always pulls slightly to to right and the front tires cup like crazy.I have had the alignment etc checked and it seems that if you run a tire with open tread blocks on the edges, you will get cupping.I have less cupping (well actually none) when I run an over the road tire instead of a "cross country" tire.

[FusoFG]

We just got back from 5 weeks in Canada.

... The truck has always pulled slightly to the right on some roads and over many miles this is probably the cause of the cupping.

I had the front end aligned last year. I have not weighed the corners.

Does anyone else have any front end pull or wear issues?

My plan is to replace the OEM Yokohama tires with Toyo M55's and to rotate the tires at every oil change (6000 miles).

Thanks
Tom

Tom_D

Sometimes both my 93 and 04 Fuso pull very slightly to the right but only on certain roads. On some roads they go perfectly straight.

It definitely gets worse as the tires wear.

The outside of the passenger tire and the inside of the drivers tire wear first.

The manual calls for rotating the tires at 6000 miles I think. So you would at the very least want to swap the front tires every 6000 miles.

There is no front end alignment adjustment other than toe in and that doesn't affect pulling left or right.

I have been told by the dealer in New York that it's caused by "radial tire steer", but I don't know what that is. Something to do with uneven loading maybe?

The dealer in florida told me my 93 had an axle designed for right hand drive trucks and the camber was set to cause the truck to pull slightly to the right so it would climb up the crown of the highway when driving on the left.

They replaced the front axle for free and with new tires on the front the problem went away.

But I think it was the new tires.

It might pay to have the camber and castor measured and see if it is correct and makes sense. Nascar certainly uses different camber on each wheel to make the cars turn left.

Does it happen more on crowned roads?

I would also weigh the truck. Separate weights for the corners would be best, but at least the right and left side.

I have often wondered it the rear axle was slightly cocked to one side. Nascar certainly does that to make a car turn.

I have heard about companies that do real axle alignment on semi tractors and trailers but I haven't found one yet.

Both trucks drive perfectly with new front tires.

I rotate the tires according to the manual every 6000 miles and that pretty much eliminates the problem.

We drive our 2004 on a 3 - 4 month trip each year of about 10,000 - 12,000 miles, so I have started buying 2 new front tires every 12,000 miles and moving the old front tires to inside rears, then the outside, then to the spare and then I get rid of them.

That way I always start each years trip with brand new front tires, they don't pull and I am only buying 2 tires every year or so instead of 6 tires at once every 3 years or so (easier check to write).

I know I can get more than 36,000 miles out of a tire, maybe 42 - 48,000, but I don't want to be driving a 10,000 plus pound truck on a rain slicked highway or a rocky road like the Dawson, the Dempster or Trans Labrador several days from civilization on that last 6 or 12,000 miles of tread.

I use the OEM Yokohamas. My local guy in ne georgia can't get them, but I have purchased them from TireRack.com and Les Schwab out west. Les Schwab has the best price and can get then in 5 days or so if not in stock. They also balance them better than anywhere else. A lot of places say they can't mount a wheel with a big center hole on their balancers.

Tom

[kerry]

The 99FG I recently bought has some cupping on the tires, mainly passenger front. Sometimes it pulls slightly to the right.

[Tom_D]

I am planning to switch to Toyo M55's because I can't get the OEM tires here in WA. Tire Rack has them once an awhile but It seems that Yokohama only builds to demand. The Toyo's have a less aggressive tread and might help.

On last years trip up the Dempster I ran new fronts and the truck still pulled a little (worse on crowned roads) but no cupping issues and no vibration. I was just lazy this year and didn't rotate the fronts to the back. I think rotating every 6000 miles will help.

Once I get the Toyo tires I will comment on how they work. Toyo M55's are available from Les Schawb in the west and they look like a suitable replacement.

cheers
Tom

[dhackney]

Our Fuso was very crown sensitive and would pull to whatever downhill side of the crown the truck was on. I took it to a truck body shop in Altoona, Iowa and had them do a two-axle, four wheel alignment.

The tech was the most "take pride in my job" person I have dealt with in a long time, especially related to vehicles.

He spent the entire afternoon on it. Took it out for three or four test drives. Aligned the axles to within .001, rotated the tires, adjusted the toe-in, etc.

He was very frustrated because he could never fully eliminate the crown-sensitive pull, but he improved the situation tremendously.

We had some cupping happening before we had the truck two-axle aligned, but have experienced none since then.

I just rotated the fronts after about 15k miles in that position. They did not have any cupping.

Our truck probably weighs as much as all the other rigs listed so far put together, so YMMV.

I recommend finding a shop that rebuilds collision damaged trucks in your area and have them align both axles. In my experience, it is very much worth the cost.

And BTW, the Fuso FG is a worldwide vehicle with the majority of sales in left hand drive countries, so I don't think the "right hand drive axle" story has much merit. AFAIK the front axle is the same part number in all countries.