[Idontknowanymore]

Hi, I’ve had this trailblazer for awhile and every time I take it out after a few minutes the chain falls off and splits the sprocket hub from the axle housing in the rear and this is the 3rd time I’ve replaced it because I cannot figure out what’s wrong.

 

[FPD218]

Welcome to the forum

 

[latebird]

You either adjust the chain incorrectly or have bad swing arm bearings - it appears to me the axle is being pulled forward under acceleration causing excessive slack in the chain, the chain then rides to the top of the teeth of the sprocket and the chain walks off the sprocket.

Actually, the entire drive line needs to be inspected and rebuilt - there may be a problem with the transmission, a missing chain guide, bad swing arm bearings, a crack in the swing arm, a crack in the frame or other undiscovered problem.