Rebuilt Differential

[Roger G.]

I may be looking for a rebuilt differential, prefer 'correct'.
I'm not sure whether the currently installed differential is the original though it had been abused by past owners long ago.
The casting has been damaged, I'll probably look for a replacement.
Can anybody recommend a source for a correct differential, 70 big block?

[Joe L.]

Re: Rebuilt Differential

I may be looking for a rebuilt differential, prefer 'correct'.
I'm not sure whether the currently installed differential is the original though it had been abused by past owners long ago.
The casting has been damaged, I'll probably look for a replacement.
Can anybody recommend a source for a correct differential, 70 big block?

Roger------


Ikerd's Corvette would be one source. www.ikerds.com

[Robert C.]

Re: Rebuilt Differential

Roger

i sourced my period correct differential from

http://www.duntovmotors.com/corvette-parts1.php

im very happy with the diff now for several years

[Gary R.]

Re: Rebuilt Differential

Roger,
Ikerds probably has the most bare housing to select from. There are other places online but you should always ask for pictures of it INSIDE and out. The 70 housings are only different in the fact they have 3 letter prefix stamping compared to 2 letter the other years had. I don't know why this is but it is. I think I have a couple in my stock but I am preparing to move a lot of parts so I might not get a chance to check right away.

Value is based on condition and if you want a complete rebuilt diff that varies a ton from one place to another. I have had in plenty of "rebuilt" diffs from many places you would be surprised at the work I have had to correct. I have the pictures of some of the things I have seen. Again I advise you to check it out before you buy or have one built.

Questions to ask

1- Are USA Timkens used?
2- What brand of gears are used, there is only one place left that makes them in the USA and the quality is better then the others. I just set up a set of 373's over the weekend to a perfect pattern.
3-What RG bolts are used? Stock or ARP, there is a big difference in the new kit bolts and the ARP's
4- What size pinion yoke is supplied - you need to know what size your driveshaft joint is, 1310 or 1330.
5- What type of posi clutches are used?
6- Is the posi case checked for cracks
7- Does the housing come with the caps and are they fit to 001" rock?
8 Look at the LH side of the housing for gouging- from a broken RG bolt- not uncommon
9- Look at the axle seal bores, is there an 1/8" lip at the bore?

I want to be clear, I am not soliciting your work. You choose the place you want to work with but if you don't ask those questions and look at pictures you may be very disappointed in what you get.

Another very important question I ask when talking to an owner, how much power to you have and how are you going to use the car? I build these diffs for power up to 900hp and can tell you a stone stock vette diff is not going to last with 450+ hp and some abuse. Not many here on NCRS need to build a diff that goes beyond 400hp but there are plenty out there that still push these cars very hard and installing a engine with 2 or 3x the power level it was designed for will very often break many parts south of the flywheel. If you would like to see pictures let me know, if you have any questions I can help with again feel free to contact me.

Good luck in your search.

[Joe L.]

Re: Rebuilt Differential

I may be looking for a rebuilt differential, prefer 'correct'.
I'm not sure whether the currently installed differential is the original though it had been abused by past owners long ago.
The casting has been damaged, I'll probably look for a replacement.
Can anybody recommend a source for a correct differential, 70 big block?

Roger------


I should have mentioned, I thought you were just looking for a correct CORE and planned to have it rebuilt. I suggested Ikerd's as a source for a CORE. Regardless, I'd suggest purchasing a core and having Gary Ramadei rebuild it.

[Joe L.]

Re: Rebuilt Differential

Another very important question I ask when talking to an owner, how much power to you have and how are you going to use the car? I build these diffs for power up to 900hp and can tell you a stone stock vette diff is not going to last with 450+ hp and some abuse. Not many here on NCRS need to build a diff that goes beyond 400hp but there are plenty out there that still push these cars very hard and installing a engine with 2 or 3x the power level it was designed for will very often break many parts south of the flywheel. If you would like to see pictures let me know, if you have any questions I can help with again feel free to contact me.

Good luck in your search.

Gary------


I totally agree. For many years I have been hearing folks talking about maximizing horsepower in their C2 and C3 Corvettes. I've always told them that unless they are willing to seriously upgrade their differential (and make it appear very non-stock in the process), they're following a foolish path. 450 HP is the absolute most that I would feel comfortable with a stock differential and, even then, I would consider it marginal.

The fact is that the 1963-79 Corvette differential assembly is just not that strong of a unit. In fact, I don't even think it was actually adequate for applications like L-88, ZL-1, or LS-6. I think it was extremely marginal for 1970 LS-5.

[Terry M.]

Re: Rebuilt Differential

I may be looking for a rebuilt differential, prefer 'correct'.
I'm not sure whether the currently installed differential is the original though it had been abused by past owners long ago.
The casting has been damaged, I'll probably look for a replacement.
Can anybody recommend a source for a correct differential, 70 big block?

Roger
You can not do better than Gary Ramadei. He knows what he is doing and is, as we used to say: "A straight shooter." You get what you pay for if you shop price for a differential or steering box rebuild. Gary will make it better than GM did and unless you abuse it, it will last longer than you will.

[Roger G.]

Re: Rebuilt Differential

Roger,
Ikerds probably has the most bare housing to select from. There are other places online but you should always ask for pictures of it INSIDE and out. The 70 housings are only different in the fact they have 3 letter prefix stamping compared to 2 letter the other years had. I don't know why this is but it is. I think I have a couple in my stock but I am preparing to move a lot of parts so I might not get a chance to check right away.

Value is based on condition and if you want a complete rebuilt diff that varies a ton from one place to another. I have had in plenty of "rebuilt" diffs from many places you would be surprised at the work I have had to correct. I have the pictures of some of the things I have seen. Again I advise you to check it out before you buy or have one built.

Questions to ask

1- Are USA Timkens used?
2- What brand of gears are used, there is only one place left that makes them in the USA and the quality is better then the others. I just set up a set of 373's over the weekend to a perfect pattern.
3-What RG bolts are used? Stock or ARP, there is a big difference in the new kit bolts and the ARP's
4- What size pinion yoke is supplied - you need to know what size your driveshaft joint is, 1310 or 1330.
5- What type of posi clutches are used?
6- Is the posi case checked for cracks
7- Does the housing come with the caps and are they fit to 001" rock?
8 Look at the LH side of the housing for gouging- from a broken RG bolt- not uncommon
9- Look at the axle seal bores, is there an 1/8" lip at the bore?

I want to be clear, I am not soliciting your work. You choose the place you want to work with but if you don't ask those questions and look at pictures you may be very disappointed in what you get.

Another very important question I ask when talking to an owner, how much power to you have and how are you going to use the car? I build these diffs for power up to 900hp and can tell you a stone stock vette diff is not going to last with 450+ hp and some abuse. Not many here on NCRS need to build a diff that goes beyond 400hp but there are plenty out there that still push these cars very hard and installing a engine with 2 or 3x the power level it was designed for will very often break many parts south of the flywheel. If you would like to see pictures let me know, if you have any questions I can help with again feel free to contact me.

Good luck in your search.

I may be interested in taking advantage of your services once I determine what I have. The car is in winter storage, I won't have access to it for a few more weeks. The car was built March 2 or 3rd, 1970. If you have a unit which fits this build date, what would you be asking for it?

Thanks everyone else who responded. I appreciate your responses.