Zf6
Drifting
Joined: Feb 2016
Posts: 1,384
Likes: 339
From: Simi Valley CA
A huge problem would be the gearing. The first gear ratio in the ZF6 is 2.66 which is almost a 2nd gear ratio. So if you use a Dana 36 most are 2.59 and the rare ones are 3.07. Either one is too high of a gear for a zf6. It would feel like you're starting off in 2nd gear. Plus the zf6 has a .5 o/d in 6th. The 2.59 gearing would make 6th gear useless until 90 mph. That could be a salt flat high speed car where you reach over 200 mph but need someone to push you to get going. The first 89s that came with the zf6 got the 3.33s and then went to 3.45s pretty quickly as the 3.33 wasn't a low enough gear.
As far as the drive shaft and c beam lining up that would be another issue. Is the ZF6 the exact same size as the auto? That's the only way the c beam would line up from the auto. The D44 snout is is a different size than the D36, so the c beam from the manual would not line up using the D36 unless it happens to be the exact same difference in length that the auto/manual transmissions are. The drive shaft you can have a little room for difference as the slip yoke has play, but not too much.
As far as the drive shaft and c beam lining up that would be another issue. Is the ZF6 the exact same size as the auto? That's the only way the c beam would line up from the auto. The D44 snout is is a different size than the D36, so the c beam from the manual would not line up using the D36 unless it happens to be the exact same difference in length that the auto/manual transmissions are. The drive shaft you can have a little room for difference as the slip yoke has play, but not too much.
Team Owner
Joined: Sep 2003
Posts: 25,393
Likes: 2,741
I don't quite get the 'thread bump'!!! Just 'DO IT' and tell all.
Thread Starter
Le Mans Master
Joined: Sep 2006
Posts: 6,050
Likes: 147
From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
Zf6
There is an 85 that already has a ZF6 installed in it to be the donor car.
the Dana. 36 in my car is out of a 12,000 mile 96 that a barn fell on and the insurance co. Totalled it.
It now has 14,000 miles on it and since it’s so low mileage, i thought I would like to keep it.
it has been in my car for about 4 months, no noise, leaks or problems, but i did inspect it and change the sealant at the batwing and replaced the gear oil with synthetic positraction gear oil.
my C5 has a 6 speed in it, and i enjoy that driving experience as well as my 57 chevy truck with the 4+3 with manually controlling the overdrive.
( 3rd overdrive is 200 rpm lower than 4thgear without the overdrive on)
auto transmissions are the absolute best in traffic, but don’t afford total control of the powertrain.
the Dana. 36 in my car is out of a 12,000 mile 96 that a barn fell on and the insurance co. Totalled it.
It now has 14,000 miles on it and since it’s so low mileage, i thought I would like to keep it.
it has been in my car for about 4 months, no noise, leaks or problems, but i did inspect it and change the sealant at the batwing and replaced the gear oil with synthetic positraction gear oil.
my C5 has a 6 speed in it, and i enjoy that driving experience as well as my 57 chevy truck with the 4+3 with manually controlling the overdrive.
( 3rd overdrive is 200 rpm lower than 4thgear without the overdrive on)
auto transmissions are the absolute best in traffic, but don’t afford total control of the powertrain.
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Melting Slicks
Joined: Mar 2003
Posts: 2,512
Likes: 49
From: Franklin IN
The Zf is a good trans but expensive to rebuild the parts are not cheap. so if you thinking of buying a used one get it CHEAP. You’d be better to buy a car with a ZF. C4’s are cheap right now.
Racer
Joined: Apr 2020
Posts: 296
Likes: 169
From: Mooresville, IN
2026 Restomod of the Year Finalist
2026 Corvette of the Year Finalist - Modified
2025 C4 of the Year Winner - Modified
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As far as I know, there are only two C-beams for the C4 Corvette. One for the Dana-36 and one for the Dana-44. Since the automatic C4s did not come with a D44, the c-beams are commonly referred to as an automatic c-beam or a manual c-beam, but it is actually the differential that necessitates the different lengths, not the transmission.
As others have said, you can absolutely swap a ZF6 into a car with a D36. All you need to do is change the driveshaft yoke to work with the ZF6. Somewhere I read that a TH400 yoke will work but not positive on that.
Something I have learned over the years, when taking on a big project over a longer time frame, sometimes it is best to just do one job at a time. Even if you have to re-do a few things when you move on to the next project.
If dealing with a D-36 and tall gears for a bit means getting your ZF6 swap done and driving sooner, I think that is worth it. You can always swap in shorter gears or a D44 later on down the road.
As others have said, you can absolutely swap a ZF6 into a car with a D36. All you need to do is change the driveshaft yoke to work with the ZF6. Somewhere I read that a TH400 yoke will work but not positive on that.
Something I have learned over the years, when taking on a big project over a longer time frame, sometimes it is best to just do one job at a time. Even if you have to re-do a few things when you move on to the next project.
If dealing with a D-36 and tall gears for a bit means getting your ZF6 swap done and driving sooner, I think that is worth it. You can always swap in shorter gears or a D44 later on down the road.
