My mechanic just installed a ring and pinion in my tranny. I love how my car hits higher RPM faster especially after changing the cams, but it makes a "humming" noise in third and fourth gear (I have a 4 speed and before it wouldn't make that noise). My mechanic says its normal. Is this true? Your comments/advice are appreciated.

 

Its normal.

 

Thanks man. Love the flames.

 

The noise may disappear as the ring and pinion wear in a bit. Nothing to really worry about though.

 

Aligning the ring and pinion requires an expert. There should be no humming if it is aligned perfectly. It is not normal. Ask me how I know? Had a new ring pinion in my 71 911S was not aligned noticed the humming and it got progressively worse. An expert coates the teeth with yellow grease. When the grease is evenly distributed on the ring and pinion the alignment is correct. Keep an eye on it. If not you will ruin it.

 

You can do that and/or measure the backlash. Bother are pretty simple and imho don't require you to be an expert.