Mismatched dually tires

[Arberg0]

From: •Razee•  (Original Message) Sent: 6/26/2005 9:03 PM
Hi everyone,
My  79 winnie came with 2 different sets of tires on each end of the rear axle, I have been having handling problems and it dosent fell like its the front end thats making this a handful to drive above 50mph. While camping on my days off I measured the rear tires and one set seems to be about .75 in. wider in diameter. Time to change tires.

The current tires are "E" rated my owners manual calls for a "C" weight range should I go back to a "C" ?  Or stick with "E"s ?

Just to verify that my hunch is correct, what kind of problems would you expect with my current set up?

Thanks for your time,
     Ray
 

 

From: OldEdBrady Sent: 6/26/2005 9:05 PM
75 INCHES?!?!?!?  Yeah.  I'd say that's a problem, since that's over 6 feet.
 
   



From: •Razee• Sent: 6/26/2005 9:57 PM
¾ of an inch ☺
   

From: cooneytunes Sent: 6/26/2005 10:31 PM
Razee......
Load range E is a better tire than load range C. I would try and get the tires to match a close as possible. With .75 of an inch difference one of the tires are taking most of the load. That's is the reason your having handeling problems at higher speeds.  Also, look at the date the tire was made, (it's on the tire) if they are 6 years old it's time to replace, if they're 7 or more years old they are past their life expectancy no matter how the tread looks, and need to be replaced immediately...Personally I'd go with a load range E for all  rear duals. There is a lot of posts on tires on the messege boards. For now I would remove all 6 of them, match them up as close as possible, or, better yet, replace them all ASAP. As Michelin says, "You have a lot riding on your tires." That's a safety issue that you never want to fool with just to save some money.
Timmy 

   

From: OldEdBrady Sent: 6/26/2005 11:04 PM
Much better.

Yes; I think it would be a problem in handling.  I would NEVER run a vehicle with mis-matched tires on the same axle, dual or otherwise.

As for the load range, I'm not much help there.
 
   


From: <NOBR>HeavyHaulTrucker</NOBR> Sent: 6/26/2005 11:58 PM
Razee, I can tell that you don't drive it very far... if you had, you would have probably blown the taller tire on one side or both sides by now.

When two tires are mis-matched on height, it causes the taller one to take more weight than the shorter one -- which translates directly to more heat-up when running.  With my trucks, I never allowed a replacement tire to be more than 1/4" different in height than the one I was putting it next to.

If both rear duals are like that, yes -- it can cause severe handling problems.  The taller tire will have more sidewall flex, which you feel as it being "squirley" or wanting to fishtail all the time -- it won't ride in a rut solidly, and it will generally feel like someone has oiled the road ahead of you all the time.

The best bet would be to match the tires by height -- you can use the two taller ones on one side, and the two shorter ones on the other side.  This should eliminate the handling problems without costing you more than a couple of "mount & balances".

John
 
   

From: HeavyHaulTrucker Sent: 6/27/2005 12:06 AM
Ed, just to set the record straight...

You can run mis-matched tires on each end of an axle just fine.  Where you run into problems is when the tires on THE SAME end of the axle are mis-matched in height.  If they are next to each other, the taller one will take most of the weight and will get hotter on a long trip -- that is a big reason that you see all the rubber on the side of the road during the summer.  Most company truck drivers either know nothing of, or don't pay any attention to, tire height matching -- they replace a single tire on a dual set with a new tire when the old one blows, and then have the new one blow out pretty soon after.

A lot of people think that this rubber on the road side is caused by re-caps; not so.  As long as you watch your inflation pressure, re-caps have longevity that will rival or surpass brand new tires.  I used to run Bandag re-caps on the drive axles of my trucks, and never lost one to a blow out -- and, using the Centra-Matic wheel balancers, I routinely got 240,000 to 320,000 miles out of a set of drive tires.

John 
 



From: OldEdBrady Sent: 6/27/2005 8:53 AM
John, I accept what you say.  But, being extra-cautious, I still wouldn't do it.  Back when I was a snot-nosed kid of 40 or so, I probably would have.  But no longer.
 
 

From: •Razee• Sent: 6/27/2005 10:56 PM
Thank you gentlemen for your responses.
Depending on availabilty four new tires will be installed this week or next