I swapped my rear gears a while back. Not long thereafter I changed my speedo gears to correct my speedometer. Now, years later, I have to replace the speedo gears again due to the clip on the tailshaft failing and chewing up my gears. So, what is the best speedo gear combo for a 700r4 and 3.42's in the rear? I have 215/65/15 tires. I thought that I should use the 15 tooth drive gear and 41 tooth driven, but TCI says to use a 40 tooth driven gear. Which is correct. Thanks.

 

I don't know which would be better, but I would say maybe check out a factory thirdgen with 3.42's and see which it uses

just a thought.

 

Aren't all factory 3.42 cars 5 speeds or would that not even make a difference?