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ZF tranny guys?

RPM289

Sr. Member
Joined
Jan 4, 2008
Messages
835
I was pulling a ZF out of a diesel truck at work and was wondering if the outer case will swap between diesel and 302 trannys?

Thanks,

Mike
 

CA Monkey

Jr. Member
Joined
Dec 4, 2011
Messages
106
Loc.
Tracy
nope. The big block / diesel ZF5's are different at the bellhousings. The ZF5 you want is from a small block 4x4 f250-350 from late 87 to 96. Donor trucks have gotten very scarce.
 

Digger556

Sr. Member
Joined
Aug 8, 2013
Messages
793
If you're asking if you can switch the case of the diesel ZF with the Windsor ZF, I believe the answer is yes, but you will likely still need the input shaft from the Windsor block version. Bear in mind that the bell housing is integrated, so you have to swap the whole housing.


ZF5's were rated for 420 lbft or 470 lbft and came in narrow or wide ratio versions. You would need to match the gear sets between the cases you intended to use.
 

sykanr0ng

Bronco Guru
Joined
Aug 11, 2014
Messages
5,363
The gasoline versions of the ZF5 were the wide ratio, the diesel versions were the narrow aka close ratio because of the narrow RPM range of diesel engines.

ZF S5-42 Close Ratio
3.79:1(Reverse), 4.14:1, 2.37:1, 1.42:1, 1:1, 0.77:1

ZF S5-42 Wide Ratio
5.24:1(Reverse), 5.72:1, 2.94:1, 1.61:1, 1:1, 0.76:1
 
OP
OP
R

RPM289

Sr. Member
Joined
Jan 4, 2008
Messages
835
Very good reading over there CA THANKS!!! Looks like it can be done but easier to find a 302 ZF
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
34,833
With the different gearing don't expect to swap the input shaft.

The only thing that might be useful is if you find a 2WD small block ZF you might be able to change the tail with parts from the diesel. That's still a maybe and a lot of work.
 

CA Monkey

Jr. Member
Joined
Dec 4, 2011
Messages
106
Loc.
Tracy
Even finding a donor doesn't guarantee it being any good. Try and find a donor truck so you can test it before you install it. Don't be surprised if going from 2nd to 3rd gear grinds a little. Almost everyone's ZF5 does because of it being the "quick shift" from second which these transmissions aren't meant for quick shifting.
 

patford

New Member
Joined
Dec 12, 2010
Messages
28
Another point of interest diesel and 460 have a shorter tail housing about inch and a quarter . Wish i know this before my rebuild it would help for future doubler build
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
34,833
Another point of interest diesel and 460 have a shorter tail housing about inch and a quarter . Wish i know this before my rebuild it would help for future doubler build

Interesting find. I could actually see this as a benefit for rear driveshaft length. Output shaft have enough spline or needs trimming, or need changing? Any idea if the modular motor version of the ZF is short or long?
 

landshark99

Bronco Guru
Joined
Oct 13, 2011
Messages
1,401
Another point of interest diesel and 460 have a shorter tail housing about inch and a quarter . Wish i know this before my rebuild it would help for future doubler build



I also believe the case is slightly taller at the shifter mount on the 460 ZF. I would need to review my measurements but it’s definitely slightly shorter.
 

75Bronc

Sr. Member
Joined
Feb 5, 2008
Messages
425
I would look for a whole truck. I found a great donor truck I drove home for $1500. I used the serpentine 351W, ZF5, Clutch, Starter, Flywheel, Master Cylinder. When you add up the parts, it was a great deal. I see them quite often around here for $1500-$2000. Just get on craigslist and look for 1988-1997 F250s that are 4x4, 351W and Manual Transmission.
 
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RPM289

Sr. Member
Joined
Jan 4, 2008
Messages
835
I would look for a whole truck. I found a great donor truck I drove home for $1500. I used the serpentine 351W, ZF5, Clutch, Starter, Flywheel, Master Cylinder. When you add up the parts, it was a great deal. I see them quite often around here for $1500-$2000. Just get on craigslist and look for 1988-1997 F250s that are 4x4, 351W and Manual Transmission.

Will the Tcase off one work or do we still need to adapt to D20?
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
34,833
The BW or NP case that comes on the ZF will NOT work. Too wide for the narrow Bronco frame. NP205, Atlas, or adapt the D20
 

Bronc076

Jr. Member
Joined
Jan 7, 2007
Messages
57
Loc.
Sierra Vista, AZ
I understand an Atlas II will bolt directly to the flange on the back of a ZF, and the output shaft on a ZF is 31 Spline. Can anyone confirm this?

My current setup is a Dana 20 adapted to the ZF in a 76 Bronco with a 5.0 and the BC Broncos cross member. If anyone has experience with this setup, or is running it I'd love to know the measurements for your drive shafts, mine are pretty new and I'm wondering if they will work.

Thanks
Rob
 

Jedeka

Contributor
Full Member
Joined
Oct 5, 2014
Messages
240
A 6 cylinder engine has the same bellhousing as a small block. Advance Adapters makes ZF to Dana 20 adapter.
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
34,833
I understand an Atlas II will bolt directly to the flange on the back of a ZF, and the output shaft on a ZF is 31 Spline. Can anyone confirm this?

My current setup is a Dana 20 adapted to the ZF in a 76 Bronco with a 5.0 and the BC Broncos cross member. If anyone has experience with this setup, or is running it I'd love to know the measurements for your drive shafts, mine are pretty new and I'm wondering if they will work.

Thanks
Rob

Call up advance adaptors. They will confirm it. And help you pick the right option boxes for it to work.
 

Digger556

Sr. Member
Joined
Aug 8, 2013
Messages
793
I understand an Atlas II will bolt directly to the flange on the back of a ZF, and the output shaft on a ZF is 31 Spline. Can anyone confirm this?

My current setup is a Dana 20 adapted to the ZF in a 76 Bronco with a 5.0 and the BC Broncos cross member. If anyone has experience with this setup, or is running it I'd love to know the measurements for your drive shafts, mine are pretty new and I'm wondering if they will work.

Thanks
Rob


I can confirm that works. I had to shorten the output shaft of the ZF by ~1/4".

Don't remember driveshaft lengths, but front and rear are the same now.

44558877170_b6fd23bbc9_o.jpg
 
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