I installed some 4.77's almost 2 years ago not knowing at the time that I was going turbo. Now everytime I do anything to improve the car it seems like 1st gear becomes more and more unusable. I've ordered a comptech diff and was planning on cryo treating my old 4.10's and slapping them in there when the diff gets here. So, like the title says, is there any reason not to do this?

 

Watching.

 

No, you should be just fine. Reinstallation of a gear set is not a problem. Even the 4.77 you will be removing could be sold and reinstalled by a new owner.. Care should be taken by the installer to get the used gear set, set like it was before. The same depth and backlash settings.

 

Theres no way to tell what the settings were set at is there? Just have to hope it was set at the factory settings? I'm the second owner, so I can't be absolutely sure. But it sounds like I'll be cool, thanks a lot.

 

The contact pattern is the most important thing to preserve...settings are a guideline, but if used solely you will get a nasty whine.

It will take someone who is good with Prusian Blue, and knows how to "read" ring and pinion patterns.

 

That is what I meant. Keeping the same settings of how the gears mess is what is important.

Again, this is a job for a very skilled tech. No your buddy who works on cars in the spare time.