I have a 98 auto with I believe 2:73's.....meaning.....absolutly NO bottom end!! I am getting started on bolt-on's soon (intake, pullies, cold air, tuner, exhaust, ect) and I know putting a set of 3:42 or 3:73 will be a tremendous wake-up.....but the little research I have done shows me I dont want to do this myself. I probally can do it.....but dont have the time or patience. Im curious what people are paying for the labor?

 

You will be better off buying a low mileage 3.42 diff (you will need a 3 series diff if you want 3.42's/3.73's) rather than having them installed.

Installation charges varies depends on where you take it to be installed. $500-$800 is what you're looking to have the diff installed in your car.

 

I have a built diff for sale with the OEM 3.42 in it.

http://forums.corvetteforum.com/c5-p...iff-brace.html

 

There is a sticky on here about how to change out your entire dif in your driveway. I am not brave enough but it looks like it can indeed be done. Just buy an entire dif, swap it out and have your computer speedo retuned to account for the different ratio

 

Throw a 2800 - 3000 stall TC in there when you do the rear end change!

 

PM sent, I'm local & may be able to help you out.

 

About $700 plus parts-new gear set $230, set-up kit $170--don't use anything but OEM
Dana Spicer.
Bon Air

 

My car currently has an A4 and 2:73's. My research revealed that while you can install 3:15, 3:42, or 3:73 gears in the 2:73 housing ~technically~ you'll either need a spacer, or a ring gear that has been specially machined for that specific housing. (the 2:73 ring gear is thicker than the other gears, and the carrier in the 2:73 rear end is machined to accept it. The other gears are thinner, ergo the need for a spacer or special gears.) Here is a link to the best post in the universe for the DIY on rebuilding your differential..... http://forums.corvetteforum.com/c5-t...ld-how-to.html

I ~really~ didn't want the higher gears (>3:15) because I don't want to run down the road at 90 MPH at +/- 3000 RPM, so for me, it was easier and far less expensive to buy a used 3:15 differential than to overhaul mine. I live in South Korea, so sometimes the wait for parts can get ...aggravating.

I found a 3:15 differential for $225, plus $60 shipping. When it gets here, I'll replace the output shafts and seals....I don't plan to ever be on a track, and am not prone to burnouts, so it'll probably last me for a while.

Here's my plan:
I'm gonna install the new differential. At the same time, I'm gonna replace the TQ converter, cam, and intake. I am considering ordering a spare PCM, the thought being that when I'm finished with the mechanical upgrades, I don't want to be waiting for my PCM to get back from the tuner (mail order.) I'm still trying to figure out this part of the equation....I'm a little confused on all the seeming options for tuning...is it possible for a tuner to install a "tune" in my PCM via the internet or email? Maybe this is a topic for a different thread...

Anyhow, the R&R of the differential is pretty straightforward.....even if it seems a little daunting to you, you can probably find someone local who is a pretty good wrench turner to help you out. Doing it yourself would be a great way to get to know your car better, and save some money at the same time!