I noticed that my front tires were cupping at 8,000. The tire were upsized at the dealer to 275x70x17 goodyears. I went to the dealer and they said to take it to the local goodyear dealer. The dealer was supprized to see those tires on this truck. The tires are C rated not E rated.

The tire dealer said that he thought it was a suspension problem, if you bounce the front of the truck the right side is stiffer than the left but both front tires look about the same.

I am going to go back to the dealer. Any suggestions or comments. I am going to try to get the suspension checked and a new set of E rated tires.

 

Well first off the dealership should put the proper tires on your truck. Where I am you have to run E rated tires or else insurance is invalid.
As for cupping of the tires, you mean the centre is not worn but the outer edges are.
What tire pressure are you running?

 

Have the dealer give you your proper tires because the ones on there won't hold a load as designed by DC. Also have the dealrer do a complete alignment on the truck. When they ship them they compress one side of the suspension down real hard on the trucks with the block and tackle to keep it from coming off the truck.

 

The tires seem to be wearing evenly acrossed. The cuppling is like every other tread or **** is worn down lower than those around it.

 

i have owned several vehicles that cup tires and a few that didnt. i have been told all kinds of expensive fixes. the ONLY one that i have found to work is to just rotate the tires at a low enough mileage before they start cupping. once a tire begins a wear pattern it will almost always continue that pattern until worn out.

 

I agree with rotating the tires. I try to do mine every 3000 miles or so. But, I did have a set of Mickey Thompson 315x70x16 on my 1st gen that they would start to cup before I rotated them. I then went to internal balancing instead of the weights on the rim. That took care of the cupping within 1500 miles. It just went away and the ride was smooth. I have used Ceramic Beads ever since and have no complaints.


http://www.innovativebalancing.com/index.html

 

What load carrying capacity do C rated tires carry? Are they even rated high enough for the weight of the Cummins? I was trying to google what 275/70/17 c's were rated for with no luck. I've seen D's on our Dodge's but never C's.

 

Dynonan

i Had the same problem with my goodyears factory tires. I Was waiting to rotate every 10,000 miles thinking that would be a good number. guess i was wrong, I took my truck in the have the tires rotated and the tire MAN told me to bring it in atleast every 5,000 with these tires, i know he is not trying to make a buck off of me for the rotation because they do them for free. We had the same problem with my dads truck ( 2002, 4x4 1500) so i dont think its a weight thing as i was told befor, just maybe a Goodyear tire thing But i am no expert, just my opinion. And the Tire tech said that he has seen this alot with these tires.

 

load rating on a c rated tire is 2600lbs! so about 5200 for the front of the truck total I don't think that is enough.. do you??

 

I think thats too light of a tire rating for these heavy front ends.

 

A cop and accident investigator once posted that if you get in an accident with C rated tires you can be liable even if it was not you fault.

Pete

 

I spoke to the service manager today and he was very disturbed that the sales department put C rated tires on my truck. He said that they should have been E rated and that he will call me back Monday.

 

Another question.
I upsized to 275's for fuel economy on the highway. What is the best size for economy? I have read some post that say 315's will rub a little but 305 do not, would that be to big and actually hurt milage?