Community Forums

baraff · 04-13-2014, 01:13 PM

I have a Winnebago Aspect on the E450 chassis. Three years ago I bought a full set (6) of BF Goodrich Commercial T/A tires to replace the rotting Michelins. On a recent trip to Tucson I had two go bad, (belt separations), the left and right rear outside tires. All these tires have 26,000 miles.
So my question is, defective tires or a problem with the suspension or bearings? I know the motorhome is not overloaded, I had it weighed and we're well under the 14,200lb GVWR. I had replaced all the shocks with new Bilsteins, and last year installed rear air bags. Inflation was within the specs, about 78psi rear, 60psi front.
Anyone have any thoughts on this, or advice?

andy29847 · 04-13-2014, 02:24 PM

Your problem sounds like tire pressure issues to me. You seem certain of your tire pressure so I am hesitant to mention this, but tire pressure gauges are not very reliable. If you are checking pressure with an older gauge, or using one that has been dropped or otherwise subjected to "hard knocks", I would verify the accuracy of my gauge 1st.

John Hilley · 04-13-2014, 02:43 PM

Sounds like low tire pressure to me. What pressure were you running in them. Are you sure the pressure on each pair were identical. If the outsides that separated were higher, they would be carrying more load.

Tom N · 04-13-2014, 05:13 PM

A problem I see with some 16" LT tires used in a motorhome application is not a high enough "load range".

TeJay · 04-13-2014, 05:15 PM

To the best of my knowledge suspension, shocks, or bearings don't directly lead to ruined tires or cause tire separation. As already stated low tire pressure increases the heat and excessive heat will cause tires to separate. Double check the recommended tire pressure and as stated check your tire gauge.

While the total weight of your coach was within specs it is possible that one side/corner was overloaded. That combined with somewhat low pressure could have contributed to one loosing air. Then maybe you drove some miles with just three tires holding up the rear end. That may have heated the other side which eventually failed as well. It could very well be a series of circumstances that cause two tires to fail. At least consider those angles because I know the tire manufacturer will consider them before they honor a warranty issue. Who knows how long you ran with a flat. You didn't explain the circumstances of how you realized that you had a flat.

Let us know what is eventually determined to be the problem. We all can learn.

TeJay

Tom N · 04-13-2014, 05:43 PM

Separation can also be caused by over-inflation and impact damage.

baraff · 04-13-2014, 08:18 PM

The tires never went flat. They held air, but broke down internally, with tread or belt separation causing an bulge. The vibration was very bad. I have a TPMS system, and monitored the pressures and temperatures. The temperatures never exceeded 90º on any tire.
Last year (Spring 2013) we drove down I-65 on the way to Florida. The condition of the road at that time (Chicago to Louisville) was so bad that our motorhome was damaged by a chunk of flying asphalt from a pothole. ($1500 repair) We hit several, some of the worst I have ever experienced. I wonder if impact damage was done then and took six thousand miles to fail.
Fortunately I bought these at Discount Tire and bought the warranty certificates, so they are covered. I had one replaced under warranty in Tucson, and the other failed on the return trip. I'll be paying them a visit next weekend and will have all the tires pulled and inspected at that time.

TeJay · 04-14-2014, 08:36 AM

Baraff,
Now that we have a little more information what you described can absolutely happen. Back in about 2000 six of us were heading up to Canada for some fishing in our 1999 DS on the F-53 chassis. I was driving through KC. I hit a pot hole so hard my cup of coffee setting on a shelf next to me completely emptied but the cup never moved. I should have stopped and examined the tires but didn't know enough at the time. We drove another 300 miles and the inner left rear tire completely came apart. I know today that I damaged the tire by hitting the pot hole and it eventually it went flat (no TPMS at the time) and we ran on it flat which caused all the rest of the damage.

Yes you can damage a tire by impacting something do internal damage and not have it show up for many miles.

It's great that you have a warranty to fall back on.

TeJay

tderonne · 04-14-2014, 09:03 PM

Roger Marble's RV Tire Safety blog is a VERY worthwhile read. He's a former tire engineer who did lots of failure analysis. He has many examples with pictures there.

Wrecked tires are gone I assume?

Old Radios · 05-16-2014, 05:54 AM

Quote:

Originally Posted by baraff

The temperatures never exceeded 90º on any tire.

Your temp reading does not sound right to me. Mine can hit 90 sitting in the driveway. I do not have TPMS with temp monitoring but would guess that the temp reading is from the sensor at the end of the valve so actual tire temp would be higher.

This has made me curious as to what others here that have TPMS with temperature normally see for temps?