I have a M21 in a 67 chevelle big block. The tranny roars when in second gear and gets worse when additional pressure is applied to shifter toward second gear. The builder sees nothing wrong says it is shifter issue-Hurst Comp Plus. Any help would be appreciated.

Did he change any of the gears when the trans was rebuilt? They need time to wear a patten on the themselves.

Thanks Mike The tranny was pulled for this reason,no new gears, it appears that the shift collar is rubbing on the cluster gear when fully engaged, Any clues?

is the shift collar on backwards? I did that when i rebuilt mine, but caught it before i put it all together. I noticed it rubbed on the cluster...

This is the deal. The 3-4 slider or collar as you call it from the factory has a blunt edge. People not knowing this will accidently stick it on 1-2. The unit will work but the slider when in 2nd gear will rub against the countergear because it is not clearanced or tapered in this area as the 1-2 slider is. New sliders are all tapered and work in both positions.

Paul
www.5speeds.com

Dear Paul, Believe you have nailed it again.Thanks for your help!!!!