looking to change out a 3.08 for a 3.55 and a bowtie 700r4 conversion from a th350. anybody have opinion on where to purchase a 3.55 differential. just want to swap out my old 3.08 for a rebuilt 3.55. does ecklers and all the other guys {mid-amrica} etc. use the same supplier?

 

Just swap the gears,..keep everything else. Richmond sells 3.55's thru Jeg's or Summit for about $175. Also get the install kit and take it all to your mechanic (someone who knows what they're doing).

He'll charge you from $100 to $200.

Then you're done.

 

Keep in mind you get what you pay for. Richmonds gears run about $270 from Summit and are known for howling. I use Toms which are a better gear in my opinion,but even with them I have one set now that is howling. Finding someone to set them up for $200 labor is a great deal- I charge $475 to custom build and tune a diff. I believe if you look at the catalog jobs and deduct for the parts they use the labor will be $400-$500. I've seen local shops charge even more.

 

100%

 

I recently replaced my differential, old one didn't like the new engine.

I read the posts here and did some checking around, I wound up buying a rebuilt differential from a shop in Beloit WI. Stevens Corvette.

I was tied up at work and didn't have the time to replace it myself so I brought it to the local race shop in town. The mechanic said the guy who rebuilt it really knew his stuff and he didn't need to do anything to it but bolt it in and fill with fluid(s).

You can give this shop a call at 1-608-365-0911, you'll find his prices lower than just about everyone, but the quality is first rate.

He rebuilds other parts for Corvettes as well, traling arms etc.

 

Lots of myths here in the gear department. There are only two gear manufactures in the states that actually make gears, Richmond and U.S. gear. They both brown box gears even though they say they do not. I am sure that Toms uses the U.S gear which is nice, they also are sold under the name of Motive and I am sure that is who makes the Randy's also. DTS I know uses the Richmond, that is where I get some of mine from and they are fine. Everyone complains of gear whine and that is a installation problem. Now if you are installing a 4.10 and lower(shich means higher numerically) then you will hear some pinion noise if you are listening for it. You have a bearing turning and metal to metal contact. Ask yourself if you can hear your trans whine or your engine running? The diff is the same thing, in a Corvette the back of your seat is in line with the pinion on the diff. If your Corvette has quiet exhaust and you roll up your window with the radio off, you will hear the diff, stock or rebuilt any manufacturer. The richmonds are a great gear and so is the U.S gear, you cannot go wrong with eiter one. The 3.55 is a great gear especially when there is going to be an overdrive, I also would not look past the 3.70 gear as an option. We build them here in house and we do not do any (half) rebuilds. What I mean by this is we first disassemble and clean the rear, it is then magnafluxed to find any cracks in the carrier assembly. After that is it put back together with the new gear, new clutches, new bearings and seals and setup for a great pattern and correct backlash and preload which is very important if you want it to last. Then we back it with our 3 year unlimited mileage warranty. The rear is $795.
Thank You
Justin Abbott
Zip Products

 

Capt T-

IMHO i would recommend sending your unit to gtr1999. I placed 3.55 gears (from Tom's) into my pumpkin using Gary's instructions. the Posi unit was easy to set up, the backlash on the gears was tedious ( I used a shim set instead of the crush sleeve for the pinion gear), and spent the money for new yokes and all new bearings and seals. Although I learned alot and had fun doing this job, next time i will send my stuff to Gary to do. He apparently has all the tools- i had to scrounge and travel, and make some to press everything out (or in). that alone is worth the price of having him do it.

i really cannot say anything about noise yet- my project is progressing at a glacial rate. it may be another year before it is running.

PureSilver

 

PureSilver, before you discount us, since you are so close why don't you stop in a see what we do with diffs. We are on the cutting edge of technology where we are actually cutting the path on some of the newer stuff. The old cast iron diffs are cake walk compared to the newer ones. Come on over and take a look, but no pictures please

 

3.08s will go well with a 700r from what I've heard. 3.55 u might wanna go with the 2004r.
ESU

 

We only use US Gears as well. 9 times out of 10 Richmond gears are nothing but trouble. I wouldn't say that there are only 2 gear manufactures as Yukon gears are made offshore and thats all Randy's Ring & Pinion uses. And to be honest those are junk as well. You can't even get a good pattern on a new set gears.(Ask me how I know)