I'm hoping to change the gear in my transmission so that I can synchronize the rear end with the speedometer. My transmission is a THM350 and my gear is a 3.42 Richmond gears limited slip differential. Can anyone give me an idea of what gear I need? It's for a 73 Olds Cutlass . Thanks!!

 

This thread has some good info with links to online calculators that can help answer your question. You'll need to know your axle ratio (3.42 in your case), tire size, and how many teeth in your drive gear. Probably best to check the drive gear and not assume which one it is.