Attention: TDR Forum Junkies 
SQUEAK... ... . SQUEAK... ... SQUEAK... ..... SQUEAK
Word of warning, don't do the poly mounts. Use OEM parts.
Do you or did you have poly cab mounts? Plain poly suspension bushings will definately squeek. My understanding was that they do that because unlike a rubber bushing which deflects, a poly bushing must rotate(hence the squeek). That was supposed to be the reason for graphite impregnation on upgraded ones. Cab mounts are primarily for isolation of vibration. They should not squeek like in a suspension application should they? Just like a poly engine or transmission mount, I would expect an increase in vibration, but not a noticeable pattern of squeeking. I admit I've only ridden a short distance in one truck equipped with poly cab mounts, but I noticed no squeeks at that time.
