trailer suspension

valhalla360 wrote:

propchef wrote:
OP, the suspension on nearly all bumper-pull RVs and 5th wheels is state of the art directly from the 1920's. VERY rudimentary. It's one of the major causes of tire failure.

Just because it's been around a while, doesn't mean it's bad.

Your heavy duty pickups all use leaf springs. I think only Dodge has tried coil springs on the 3/4 ton trucks (1 ton they still use leaf) and there are mixed thoughts on that use of more advanced technology.

Typically failures can be traced to...road debris, overloading and/or low tire pressure. Do you have any documentation (not anecdotes) that leaf springs are the cause of tire failure? I've never heard that before.

I think you're reading into my post a bit, so let me clarify. I never said leaf springs were "bad" or even the cause of tire failure, I said RV suspensions are very basic and rudimentary and that these overly-simplistic barely-meets-spec axels need as much attention and maintenance as the inside of the RV. Who checks them for alignment? No one. What you can find with regularity are examples of RV leaf springs and associated shackles failing.

That 3/4 ton truck likely has progressive leaf springs (most do) and are very different from the ones on a TT which are usually a single or thin double, and are rarely progressive. Passenger vehicles will also have shocks and other links to help locate and dampen the axel.

Absolutely true that overloading, improper inflation, and road debris cause tire failures. So does severe misalignment, which these axels are prone to, with many coming from Dexter (or insert other brands here) off by more than a few degrees. This is something that manifests itself more with a twin-axel setup but can still be an issue on a single. The worst part is that there are no adjustment points, and an axel that is off must be bent back into position. The out-of-position tire heats up and fails, and the owner storms off complaining about "china bombs."