Yes things wear out. Especially after as many years as that thing has been in operation. There is a trolley available that will replace the one you have. The exact replacement for your trolley hasn't been available for about 20 years. You can check out part number 41A3489. Sells for $26.99 or there abouts.

trolley is pretty simple. tee shape. attaching point for cable. another point for lift bracket. mine is cast alum. seems the replacement one is stamped steel. maybe it will fit?

It will fit but will not be an exact replacement.

You can always just assemble one from stock shapes, or even simply pop-rivet a patch over the worn location.

got a used one. opener is so old, there are clips on drive chain to trigger up/down limits. the trolley has the cable mount on the opposite side as original. and threaded rod for chain tension is shorter. so lengthen chain, or use new rod and shorten chain.

Let's see now. If the cable mount is on the other side it will be going down when it's going up and going up when it's - oh well.

I just turned trolley around. Not sure what rod is called that connects chain to cable. Tension rod? Some trolleys do not have it. U mount the small springs to it so the lift cable has some cushion. My new rod is shorter so I need to lengthen chain or move cable pulley about 1 " closer to opener motor.

hey, my trolley is backwards? works fine.