I had the same issue with a similar aged bar and this is what I found based on suggestions from Roadmaster.
If you look at the coach end of the arms there is a rubber seal/plug at that end of the arm. That seal can wear or be torn over time allowing dirt and gunk to get in the back of the arm and cause it to get hard to move in and out. You can also get a lot of dirt inside the mechanism if the arms are collapsed "dirty" and w/o any silicone to keep them lubed.
That seal/plug is just press fit in the back of the bar. Roadmaster suggested removing the seal/plug (gently pry/wiggle out with a screwdriver) and then using WD-40 to lube/clean the bushing inside there. The tech basically said "lube the p*ss out of it" with WD40 while moving the arm in and out.
As you do this it will get easier and easier to move. Once you get it loosened up like new, then reinsatll the seal/plug and you should be good to go.
If you have a bad seal/plug, Roadmaster might send you new ones gratis.
Since that happened, I found the best process to keep from happening again is:
EVERY time I disconnect the toad, the first thing I do is wipe down the stainless arm with a clean paper towel. This keeps the arm from drawing any dirt back into mechanism when it is retracted.
Second thing I do is spray the stainless arm with a good dose of silicone spray before I retract/collapse the arms.
Since I have been following this procedure EVERY time, I have had no issues with any binding or stickiness of either arm.
Tom & Mary plus Lilli the Havanese
2017 Entegra Aspire 44B,
450 Cummins, Spartan K2
HRRVC #106803
2017 Buick Enclave toad:)
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