Differential encyclopedia for C4's
Thread Starter
Racer
Joined: May 2017
Posts: 452
Likes: 136
Differential encyclopedia for C4's
Has anyone ever put together a "Sticky" or comprehensive guide of C4 Rear Differentials? What gears fit in which housings? What Posi Units work in D36's and D44's...same for carriers. Thick gears vs. thin gears?
There seems to be a bit of mystery on this. I'm an "Old School" 12" Posi/Dana 60/Ford 9" kind of guy and since I now have a C4 I want to learn more.
I know that all Automatics came with D36's and Manual shift came with D44's I have heard that there are different carriers/Posi units for D36's and the break is 2:59~2:73/3:08~3:31 (or maybe even 3:42's).
What gears work with which housings/carriers?
What's a good source of factual information on this?
There seems to be a bit of mystery on this. I'm an "Old School" 12" Posi/Dana 60/Ford 9" kind of guy and since I now have a C4 I want to learn more.
I know that all Automatics came with D36's and Manual shift came with D44's I have heard that there are different carriers/Posi units for D36's and the break is 2:59~2:73/3:08~3:31 (or maybe even 3:42's).
What gears work with which housings/carriers?
What's a good source of factual information on this?
Melting Slicks
Joined: Nov 2013
Posts: 3,451
Likes: 336
From: Greater Cincinnati Area.
I buy a lot of stuff from these guys.
https://www.ringpinion.com/DiffWizard.aspx
Although I haven't done the vette yet, they have a calculator/wizard that works very well for other vehicles.. Maybe you can give them a try?
https://www.ringpinion.com/DiffWizard.aspx
Although I haven't done the vette yet, they have a calculator/wizard that works very well for other vehicles.. Maybe you can give them a try?
Team Owner
Joined: Sep 2001
Posts: 62,140
Likes: 1,729
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
If it came with a 3.07/3.31/etc., its a 3-series case D36. 2.59/2.73/etc. are 2-series cases. You cannot use the 3-series gears from a D44 in the D36, to my recollection, but you can use other 3-series D36 gears in a D36 case.
You can re-gear to any other 2-series gear ratio with nothing other than the change in the ring and pinion. To go to a 3-series gear ratio, from a 2-series case, you can either use a gear set with a thick ring gear or change the differential, posi, internal or ring gear case.
You can re-gear to any other 2-series gear ratio with nothing other than the change in the ring and pinion. To go to a 3-series gear ratio, from a 2-series case, you can either use a gear set with a thick ring gear or change the differential, posi, internal or ring gear case.
Racer
Joined: Jul 2017
Posts: 259
Likes: 38
From: Volcano CA
I'd like to change my 2.59's to the 3.54's ('96 LT1/auto) and have a shop that would love to do it and is ready, but find conflicting info regarding speedo calibration (gear vs. electronic gadget), custom tuning due to new found higher shift points(?), etc... that all goes along with swapping gearing. I don't want to take the plunge until all the mysteries are solved and I have my ducks lined up.
I understand that many different cars/rear ends are out there so it's tough to put it all in one post or thread.
I'll keep reading......
Team Owner
Joined: Sep 2001
Posts: 62,140
Likes: 1,729
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
I'd like to change my 2.59's to the 3.54's ('96 LT1/auto) and have a shop that would love to do it and is ready, but find conflicting info regarding speedo calibration (gear vs. electronic gadget), custom tuning due to new found higher shift points(?), etc... that all goes along with swapping gearing. I don't want to take the plunge until all the mysteries are solved and I have my ducks lined up.
I understand that many different cars/rear ends are out there so it's tough to put it all in one post or thread.
I'll keep reading......
I understand that many different cars/rear ends are out there so it's tough to put it all in one post or thread.
I'll keep reading......
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