After having a full set of M&M Aluminum IRS bushings setting around for a while now ,I finaly got around to putting them in. All I can say to anyone on the fence about this is DO IT ! It took two laydedback style days on the floor of my garage to put them in by the time I matched the pinion angles,results?? No vibe at ANY speed form 0 to 145 ( in Mexico of course). So if your on the fence About this dont be noise incraes was minimal and no vibe is defently worth the trade off.