Rotating rear tires

[cmeadows]

Rotating rear tires — I used to like the idea of mounting the rear dual tires and running them as a set until replacement. This works fine if the tires get old and need to be replaced before they wear out. But, I’m going to start rotating the rear dual tires. We wore out a set in 3.5 years at 45k miles. No complaints. The tires had 10k miles of towing and 1000 miles of gravel road and crushed rock.

We needed 8k miles to complete the last planned trip on the tires. With 36k miles and nearly half the tread remaining at 6-7/32nds, I figured the tires were good to go. There was some rounding on the edge tread nearest the differential but I thought they would make the trip. The roads were more abrasive than I expected. The right rear inside tire threw the tread at 42.5k miles. After we were home (with new tires on order), the left inside tire threw the tread at 45k miles. Neither was a blowout.

Below are photos of the left rear outer and inner tires. As you can see by the wear bars, both tires are worn out. The glaring difference is the rounded edge tread that was mounted nearest the differential and never rotated. The outside tire measured 1/32nd deviation across tread. The inside tire had 2/32nds deviation across the tread with the side nearest the differential worn the most. All 4 rear tires had less than 1/32nd deviation around the circumference of the tire—they remained in balance for the life of the tire.

I will start rotating the new rear tires every 10k and plan for each side of the rear tires to spend 10k running in the harshest position— nearest the differential. I’m not expecting to get additional tread life out of the new tires, but I do anticipate even wear and no thrown treads. Rotating at home before a trip seems like a great tradeoff to changing tires on the side of the road.

Trivia . . . the tires that lost their tread were manufactured 2 weeks after the Michelin recall range on the LTX M/S tires.

We still balance with beads. Below is a photo showing what the inside looked like with the beads after 45k miles. For those interested, here’s a link to a thread on beads.
http://www.bornfreervclub.org/bulletin_ ... f=4&t=4429

[whemme]

Note sure why your inside dual should have that much wear on the inside edge. Since the duals are on a solid straight axle, there will not be any alignment issue to cause that kind of difference in wear from the outside vs the inside edge of the tire. I use Firestone Transforce HT tires in size LT225/75R16E on my Born Free and change them every 5 years and only rotate the fronts left to right. I am currently on my third set on my 2002 BF 26' RSB coach and never have had that kind of wear pattern on my rear duals.. Since I have the custom Borg Tire metal valve stems, it is difficult to rotate the rear duals and never thought it to be necessary anyway.

[bigdipper]

I had the original Michelins replaced 3 years or so back after a recall. With no rotations on rear, they were down to the wear bars at roughly 35000 miles. Wear was even. This time Michelin replaced them under the tread wear warranty. It cost me something but a lot less than buying new. While I have no opinion why your uneven wear, I would not rotate rears. I think FOMOCO recommends against rotating rears. I do switch fronts every 20,000 miles or so. Keep the pressure up! My recall was due to an epidemic of throwing tread off. One rear had lost tread while holding air. You might see if your tires were from the defective run.
Ralph

[randallrae]

http://www.tirereview.com/back-to-basic ... cle-tires/ I was told that inside tires on dual wear more than outside tires . I would GUESS your wear might be caused by the crown that most roads have .( high in the center tapering down left and right ) that would cause the inside tire to wear more towards the differential ,or center of the road .

[cmeadows]

Thanks for the advice and replies.

----Bill, the Borg valve stems would make it difficult to rotate the duals. Rotating the duals would not be necessary if the tires are replaced for age instead of wear.

----Ralph, the 4 rear tires were made 2 weeks after the recalled date range. We keep the rear pressures at 80 and monitored frequently. I might check on a tread wear warranty if the next set wears more evenly.

----Randallrae, I’ve also read that the inside duals carry more of the load than the outside tires. The crown between the tire tracks in the road probably caused the wear on the inside dual tires. We travel on many secondary roads which probably have more crown between the tire tracks.

Conventional wisdom has been to not rotate duals and wear them out as a set. I followed that on a previous dually vehicle and never had a problem, but we replaced the tires on that vehicle due to age instead of wear. When we bought our Born Free, the tread on the tires looked new, but they needed replaced due to age.

This is the first set of duals that we’ve worn out. With the amount of edge tread remaining on the outside tires it seems that, if I’d rotated them, some of that tread could have worn down a little and prevented the inside tires from taking all of the wear which lead to the inside tires throwing the tread. I may be wrong, but I’m going to rotate the new set.

[randallrae]

My inside dual , 3 years old , 27000 miles

[cmeadows]

Randallrae, your tire appears to have the same wear pattern as mine.
Looking at the sipes in the photo, it looks like there is less tread depth on the inside edge.