I've been using the same ROADMASTER towbar since 2001. (All steel) On a return snowbirding trip (2 days to go before home) one of the telescoping arms would not retract. Made for interesting hookups the next two days....(pull-thrus were not available) but we did it with a minimum of fuss.
I called Roadmaster...they asked for the serial number then gave me a "return-repair" number to put on any package. And....VERY surprisingly, told me I had a lifetime warranty !!
Took it (arm still extended)to my UPS store, where they packed and shipped it...for $94. 2 weeks later, it was returned, and better than new. (lol)
Still using it without problems...of course, things might have changed since then...happened in 2008.
FWIW.,