Okay, after numerous blow outs ( mainly right rear-but not always) and significant damage to my toy hauler caused mainly I believe crappy ST (trailer) tires made in China, I think I may have finally solved the problem.
I'm not the only one with this issue, lots of folks with Fifth Wheel trailers, Travel Trailers, Utility Trailers, etc... using the made in China ST tires have all had similar problems.
After a lot of research and the experience of many who were kind enough to post their own research and solutions here's what I came up with.
First was to up size the rims to 16" so I could install high quality Michelin Rib commercial truck tires (245/75). I was fortunate that I had 6.5" between the stock 15" tires, and ended up with a little over 4" between the tires with the new Michelin Rib tires.
The Michelin Rib tires are retread able and have steel plies in the side walls as well as the tread area. They also have a "Q" speed rating which is 99MPH continuous. Compared with the "ST" speed rating of 65MPH continuous.
Bridgestone also makes a similar tire, the Duravis R-250. I went with the Michelin's as their web site had a feed back section with countless stories of Fifth Wheelers and other recreational vehicle owners who had the blow out problems and all were eliminated with the installation of the Michelin Rib tires.
I have no desire to tow my TH at 90MPH!
However, what I have found out is that the ST tire speed rating of 65MPH is absolute, and as soon as one exceeds this speed when the tires are hot the ST tires tread will start De-lamminating from the carcass, which will give you the surprise blow out at some point in the future with NO imminent indication, and NO warning. In California, (PRK), the speed limit for vehicles with trailers is 55MPH, all of the other states that I travel in, the speed limit is 75MPH for all vehicles. I used to only tow at 65MPH because of the speed rating, and was always in the way.
Second, I found through my research that many trailer axles are miss-aligned from the factory. WTH???? With this in mind, and the fact that there are so many blowouts from the crappy Chinese made tires, it is astounding that the manufacturers are still putting them on their vehicles. One Chinese made tire was so bad the NHTSA banned these tires for sale in the United States.
So second on the list was to visit truck alignment shop that could do an alignment on the trailer axles. Part of this work was to have all of the suspension bushings replaced with bronze bushings and wet bolts installed. (Trailers come with Delrin bushings-plastic-again WTH?) I made an appointment three weeks in advance to get in there. I took vacation time to get the trailer in there and when I got there they didn't have room on their rack to do the work. The tech showed me the bushing kit, and told me he would check back later. Here is the best part, later in the day the tech called back and told me they didn't do any of the work and I had to get there before they closed to retrieve my trailer! SURPRISE! The tech told me that I should call back in a week to see when I could get it in and that they would make things right for wasting my time. Long story short, they never did and I had Edi Luna at Benchmark RV (818-504-4813) where I store my trailer do the bushing work, Benchmark had the work done in a few days.
I found an old school BEAR Frame & Wheel alignment shop in Glendora (626-335-0243), to have the camber and toe check on the trailer axles. It was no surprise to find that the rear axle had 1/4" of toe out, meaning the tires were dragging down the highway. And, the drivers side rear had 1* of negative camber, and the passenger side right rear had 0* of camber. The well seasoned alignment tech, using the old school three point alignment tool, chains and a bottle jack corrected the negative camber on the LR. Then using the same bottle jack for support, and a porta ram corrected the toe to zero inches. After the Toe was corrected they re-checked that the camber on both wheels was still at zero.
Moving to the front axle, they found the LF had 1 &1/4* of negative camber, and the RF had negative 1/4* of negative camber, and the toe was zero. Using the same method as above, the camber was corrected on both wheels. Upon re-checking the toe, this correction had created some toe out. Again, using the same method as above, the toe was corrected to zero, and then the camber was re-checked.
I am very hopeful that with wheels now running straight and true, and the addition of the best tires I could find my blow out problem will now be eliminated and maybe a little better mpg to boot.
If you have any questions please shoot me a note!
