Originally Posted by
bh85
Do you think Alivio M3100 9 speed would work? It’s the newest Alivio RD that can handle 36t. Not sure if anything changed with new ones.
It will, but I've found the Shadow style derailers like these, which don't pivot the upper pulley wheel up with cage rotation, to have sluggish shifting across the smaller sprockets of the cassette, because the chain's further away from meshing tightly with those sprockets.
Instead, I'd recommend a Deore RD-M591. It's one of the last traditional style Deore rear derailer and it's a pretty stout piece. Shimano says it will support up to 34T, but I can say from personal experience that it'll handle at least 36T.
Another option is the Alivio series RD-T4000. It's one step down from Deore in Shimano's line up and is a
current production derailer. Like with the M591, it supports up to a 34T, but I run this derailer with a 40T on one of my bikes and it clears it with ease.