XT m760 crank probs
I've got a m760 XT crankset and bb that's had about 1.5 years of riding on it. It's gotten loose. If I grab the crank arm (either side) and the frame there is play. This is very noticeable when pedaling hard.
1) Do I just need a new bb?
2) If I do need a new bb, will the old external-type FSA bb that came with my gossamer rd crank work?
Did you figure this out? If not, my guess is that your crank arms are loose. Loosen the pinch bolts on the crank, use this tool (should came with your cranks) to finger tighten, then tighten the pinch bolts back.
While you are doing this, I would recommend you clean and repack grease in the BB. Refer this in the drivetrain posting area.