I am helping a buddy of mine replace the diff from a 2.73 to a 3.42 and I am trying to see if I could gain enough clearance to just drop the trans a little and pull the rear off and put the new one in?

I really don't want to have to pull the whole thing out if I don't have to.

 

Yes no problem just watch the clearance between the back of the intake and the cowl when you lower the TT

 

Cool, thats what I needed to know. I pulled a few before when I worked at the dealer but that was over 12 years ago.

 

Like Feeler82 said you can lower diff/trans torque tube assembly enough to get the differential of the transmission and still have enough clearance between the engine and the firewall. I have done it this way quite a few times.

 

Are you installing a Z06 differential? I've been looking over six months for one and can't find. The C6 3.42 won't fit. The Z06 requires minimal modification.

 

I was thinking that it was actually a C5 automatic that they were working on (though I might be wrong in assuming that), upgrading the base C5 automatic's 2.73s to a manual's 3.42 which can be done much easier in C5s then it can in our automatic C6s.

 

You may be right. I guess we were both assuming!

 

Yeah its a z06 diff from a c5. We found it on a google search in a corvette only junkyard in Picayune, MS. If you call them make sure they don't try to rip you off. They have $650 on their site and when we called they told us $1350, we told them F U and then they came down when we told them they had $650 on their site.

Yeah we are upgrading a c5 automatic from the 2.73 to 3.42.

Didn't the c6 auto's come with 2.56? I'm not really a vette guy so I don't know.

 

How long did it take you to the point of getting access to unbolt it?

When I took out the torque tube and all it took me a little over 2 hours on a lift at the dealer years ago.

Hopefully its like riding a bike, you never forget.

 

Yes, the only ratio available in 2006/2007 was the 2.56s. In 2008/2009 a 2.73 rear became optional on base automatics and standard/part of the package on Z51 optioned automatics.
In 2010 all base automatics again came with 2.56s with the only way to get 2.73s being to order a Grand Sport automatic which came standard with the 2.73s, which is how it still is to this day.

 

step it up put a set of 3.73 and a 3600 stall before you install and snap some necks

 

If thats the case we wouldn't be putting in a whole diff. It's just easier for us to swap it.

The converter will be later down the road and a cam will go in also.

 

You don't have to remove everything, just lower it enough to get the old diff off and new one on

 

It took me roughly an hour or so. Once you get back in there it will come to you. It is not bad at all but I have done a ton of trans/diffs/clutches in vettes so it is kind of like second nature.

 

An hour to take it out and maybe an hour and a half to reinstalled. And a dealer here in Houston quoted me $700 to change out a differential in my 08.

 

Yea 700$ for removal/install on a diff is about average... that's the corvette tax...

 

$650...that seems steep. I bought a used C5Z diff last year for $400 that's just sitting in my garage as a spare.

 

Yeah. I looked on ebay and the classifieds on here and couldn't find anything . Ebay had them for 600 but the shipping would of put it over 700. I found that junk yard which was a 20 minute drive away. Plus that diff had low miles. The ebay ones had like 90k+ miles.

Update: The diff is in and the LT's are on. He has the XS Power 3 inch mufflers on. He was supposed to go to the dyno yesterday but couldn't make it. i think he is going to go next week.