1978 Vette Diff
Thread Starter
Heel & Toe
Joined: Apr 2024
Posts: 18
Likes: 2
From: Westchester, New York
Tech Contributor
Joined: Aug 1999
Posts: 15,135
Likes: 3,939
From: Connecticut, USA
That 63 carrier( housing) is worth something only to a guy with a 63 who is looking for that date code and stamping. Otherwise, it is a doorstop.
The caps are line bored to the housing, without them you will have to fit caps, - correctly. Most will not have access the caps or know how to fit them. I have a lot of stock caps and steel caps and know how to fit them. That doesn't help you since the labor would be more than the value of the carrier.
Even if you had the caps, where would get the correct side shims to build a 63? They don't come in the master kits sold today. Something vendors don't either know or tell their customers this little fact.
The wear at the seal location on both sides is from using C3 axles in it that worn down and crashed into it. The bores are still good but if it was any deeper the only fix would be to bore and sleeve it, again worth more than the housing value unless it was a matching numbers car.
Here is a tip.
Do a lot more homework before you spend any more money.
Out of the car complete diff's rebuilders pay $250 for. Market price if you will, is $400. Anything over $400 is overpriced and more than likely has issues.
If you don't know these diff's you will get burnt over and over. I have been teaching about this for decades but it's still prevalent today. Chances of finding a good used diff to bolt in without issue is slim. It is not impossible, but you have to know a lot more than you do now. I am not trying to be negative here, but if you saw some of what I have doing this work for decades you would understand better. And I get it, I bought my first vette, a 67 coupe, at age 18- there was no internet then. There were few custom builders then, even less today, and in that group even less who are honest. It has been a long road. I learned and developed more about these parts than most selling them know will ever know, yet they sell parts every day. Be careful of some rebuilders in the Lone Star state as well.
Good luck. Build the diff to your application do not trust cookie cutter builds for anything today.
The caps are line bored to the housing, without them you will have to fit caps, - correctly. Most will not have access the caps or know how to fit them. I have a lot of stock caps and steel caps and know how to fit them. That doesn't help you since the labor would be more than the value of the carrier.
Even if you had the caps, where would get the correct side shims to build a 63? They don't come in the master kits sold today. Something vendors don't either know or tell their customers this little fact.
The wear at the seal location on both sides is from using C3 axles in it that worn down and crashed into it. The bores are still good but if it was any deeper the only fix would be to bore and sleeve it, again worth more than the housing value unless it was a matching numbers car.
Here is a tip.
Do a lot more homework before you spend any more money.
Out of the car complete diff's rebuilders pay $250 for. Market price if you will, is $400. Anything over $400 is overpriced and more than likely has issues.
If you don't know these diff's you will get burnt over and over. I have been teaching about this for decades but it's still prevalent today. Chances of finding a good used diff to bolt in without issue is slim. It is not impossible, but you have to know a lot more than you do now. I am not trying to be negative here, but if you saw some of what I have doing this work for decades you would understand better. And I get it, I bought my first vette, a 67 coupe, at age 18- there was no internet then. There were few custom builders then, even less today, and in that group even less who are honest. It has been a long road. I learned and developed more about these parts than most selling them know will ever know, yet they sell parts every day. Be careful of some rebuilders in the Lone Star state as well.
Good luck. Build the diff to your application do not trust cookie cutter builds for anything today.
Thread Starter
Heel & Toe
Joined: Apr 2024
Posts: 18
Likes: 2
From: Westchester, New York
That 63 carrier( housing) is worth something only to a guy with a 63 who is looking for that date code and stamping. Otherwise, it is a doorstop.
The caps are line bored to the housing, without them you will have to fit caps, - correctly. Most will not have access the caps or know how to fit them. I have a lot of stock caps and steel caps and know how to fit them. That doesn't help you since the labor would be more than the value of the carrier.
Even if you had the caps, where would get the correct side shims to build a 63? They don't come in the master kits sold today. Something vendors don't either know or tell their customers this little fact.
The wear at the seal location on both sides is from using C3 axles in it that worn down and crashed into it. The bores are still good but if it was any deeper the only fix would be to bore and sleeve it, again worth more than the housing value unless it was a matching numbers car.
Here is a tip.
Do a lot more homework before you spend any more money.
Out of the car complete diff's rebuilders pay $250 for. Market price if you will, is $400. Anything over $400 is overpriced and more than likely has issues.
If you don't know these diff's you will get burnt over and over. I have been teaching about this for decades but it's still prevalent today. Chances of finding a good used diff to bolt in without issue is slim. It is not impossible, but you have to know a lot more than you do now. I am not trying to be negative here, but if you saw some of what I have doing this work for decades you would understand better. And I get it, I bought my first vette, a 67 coupe, at age 18- there was no internet then. There were few custom builders then, even less today, and in that group even less who are honest. It has been a long road. I learned and developed more about these parts than most selling them know will ever know, yet they sell parts every day. Be careful of some rebuilders in the Lone Star state as well.
Good luck. Build the diff to your application do not trust cookie cutter builds for anything today.
The caps are line bored to the housing, without them you will have to fit caps, - correctly. Most will not have access the caps or know how to fit them. I have a lot of stock caps and steel caps and know how to fit them. That doesn't help you since the labor would be more than the value of the carrier.
Even if you had the caps, where would get the correct side shims to build a 63? They don't come in the master kits sold today. Something vendors don't either know or tell their customers this little fact.
The wear at the seal location on both sides is from using C3 axles in it that worn down and crashed into it. The bores are still good but if it was any deeper the only fix would be to bore and sleeve it, again worth more than the housing value unless it was a matching numbers car.
Here is a tip.
Do a lot more homework before you spend any more money.
Out of the car complete diff's rebuilders pay $250 for. Market price if you will, is $400. Anything over $400 is overpriced and more than likely has issues.
If you don't know these diff's you will get burnt over and over. I have been teaching about this for decades but it's still prevalent today. Chances of finding a good used diff to bolt in without issue is slim. It is not impossible, but you have to know a lot more than you do now. I am not trying to be negative here, but if you saw some of what I have doing this work for decades you would understand better. And I get it, I bought my first vette, a 67 coupe, at age 18- there was no internet then. There were few custom builders then, even less today, and in that group even less who are honest. It has been a long road. I learned and developed more about these parts than most selling them know will ever know, yet they sell parts every day. Be careful of some rebuilders in the Lone Star state as well.
Good luck. Build the diff to your application do not trust cookie cutter builds for anything today.
Race Director
Joined: May 2006
Posts: 18,665
Likes: 2,564
Since you are in Westchester and Gary is in Connecticut, it maybe worth your while to reach out to Gary and ask if he is willing to show you first hand some of what he does.
Melting Slicks
Joined: Apr 2021
Posts: 2,642
Likes: 2,093
From: Minnesota
On a related note does anyone know a good place to look when buying a good core differential? Marketplace, Craigslist, and the internet has pretty slim pickings as far as good quality ones.
Thread Starter
Heel & Toe
Joined: Apr 2024
Posts: 18
Likes: 2
From: Westchester, New York
That 63 carrier( housing) is worth something only to a guy with a 63 who is looking for that date code and stamping. Otherwise, it is a doorstop.
The caps are line bored to the housing, without them you will have to fit caps, - correctly. Most will not have access the caps or know how to fit them. I have a lot of stock caps and steel caps and know how to fit them. That doesn't help you since the labor would be more than the value of the carrier.
Even if you had the caps, where would get the correct side shims to build a 63? They don't come in the master kits sold today. Something vendors don't either know or tell their customers this little fact.
The wear at the seal location on both sides is from using C3 axles in it that worn down and crashed into it. The bores are still good but if it was any deeper the only fix would be to bore and sleeve it, again worth more than the housing value unless it was a matching numbers car.
Here is a tip.
Do a lot more homework before you spend any more money.
Out of the car complete diff's rebuilders pay $250 for. Market price if you will, is $400. Anything over $400 is overpriced and more than likely has issues.
If you don't know these diff's you will get burnt over and over. I have been teaching about this for decades but it's still prevalent today. Chances of finding a good used diff to bolt in without issue is slim. It is not impossible, but you have to know a lot more than you do now. I am not trying to be negative here, but if you saw some of what I have doing this work for decades you would understand better. And I get it, I bought my first vette, a 67 coupe, at age 18- there was no internet then. There were few custom builders then, even less today, and in that group even less who are honest. It has been a long road. I learned and developed more about these parts than most selling them know will ever know, yet they sell parts every day. Be careful of some rebuilders in the Lone Star state as well.
Good luck. Build the diff to your application do not trust cookie cutter builds for anything today.
The caps are line bored to the housing, without them you will have to fit caps, - correctly. Most will not have access the caps or know how to fit them. I have a lot of stock caps and steel caps and know how to fit them. That doesn't help you since the labor would be more than the value of the carrier.
Even if you had the caps, where would get the correct side shims to build a 63? They don't come in the master kits sold today. Something vendors don't either know or tell their customers this little fact.
The wear at the seal location on both sides is from using C3 axles in it that worn down and crashed into it. The bores are still good but if it was any deeper the only fix would be to bore and sleeve it, again worth more than the housing value unless it was a matching numbers car.
Here is a tip.
Do a lot more homework before you spend any more money.
Out of the car complete diff's rebuilders pay $250 for. Market price if you will, is $400. Anything over $400 is overpriced and more than likely has issues.
If you don't know these diff's you will get burnt over and over. I have been teaching about this for decades but it's still prevalent today. Chances of finding a good used diff to bolt in without issue is slim. It is not impossible, but you have to know a lot more than you do now. I am not trying to be negative here, but if you saw some of what I have doing this work for decades you would understand better. And I get it, I bought my first vette, a 67 coupe, at age 18- there was no internet then. There were few custom builders then, even less today, and in that group even less who are honest. It has been a long road. I learned and developed more about these parts than most selling them know will ever know, yet they sell parts every day. Be careful of some rebuilders in the Lone Star state as well.
Good luck. Build the diff to your application do not trust cookie cutter builds for anything today.
Le Mans Master
Joined: Jun 2019
Posts: 7,645
Likes: 2,464
From: Indiana
After sum decent studying and researching i went to searching on marketplace. I found a differential part number 3899143 and it was rebuilt with richmond gears. I counted 37 teeth on the ring gear and 10 teeth on the pinion so i know it is a 3.70. I Picked it up for 275 bucks, it had clean fluid aswell as no leaks. and i had my shop foreman look at it and he says it looks good. I purchased a seal kit for the axle seals and the pinion seals. I was planning on just replacing the axle seals but if i should do the pinion seal aswell or just leave it as is without touching the internals. when i get out of class i will post pictures let me know what you guys think when i post the photos. The differential came out of another 78 corvette. It has the connections to the universal joints aswell as the mount bracket by the pinion. I ordered 6 new universal joints. made sure to get spicer 1330x and 1350x. I will be doing the work in the shop of the dealership i work at. When i remove the old differential i plan on rebuilding it as a backup or to put in when or if i want to make changes.
https://www.corvetteforum.com/forums...ay-advice.html
Race Director
Joined: Mar 2017
Posts: 11,906
Likes: 4,479
From: Virginia
I just generated another surplus 3.55 diff (and an entire chassis), when I found a built SRIII chassis.
Keep looking! They are out there. Sometimes still inside parts cars. Glad to see the OP had success!
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