Difference in ZF-5 transmissions
Laughing Gas
Joined: Feb 2009
Posts: 921
Likes: 1
From: Denver CO
On a 13, 15, or 18 spd the drop rate is about 300 rpms per gear. on a 9, 10, super 10, or srtaight 8, is about 500-600 rpms, if your an experienced driver floating the gears (using rpm band, not the clutch to shift).
New User
Joined: Mar 2007
Posts: 19
Likes: 0
From: Clovis
ZF 42 to 47
Here I was told they would not, that the 42 cannot replace the 47 because the wrong year.
If I would only lose a little torque, I don't mind because my 94 pulled great. And I liked how it shifted better anyway, I could float anything over 2nd.
I know this is an old post, but hope someone replies for a second opinion that this is ok before I start tearing apart the 94 when the rain stops!
Thanks for the hope that I might actually get a truck running this week!
I had been limping around in my 84 F250 non-4x4 until last month, when I think it blew the head gasket.
Hotshot
Joined: Oct 2003
Posts: 17,799
Likes: 104
From: Ashland City, TN
the 42 and 47 are a lot of the same.
Though, I don't know about the year thing. Travis has a 95 and he's got a 42 in his truck. He bought a 47 to replace his though.
The 47 has some more useful upgrades like a non pressed in throw out bearing shaft.
On the 42, you have to disassemble the case, with the 47 you do not.
Some other upgrades and such as well.
If you look at the pictures, they are very similar, but they made some case modifications to them as it appears to me.
As for input torque. Look at cody and the other guys on here with sled pullers running this.
The biggest fear on a zf5 is snapping the input shaft. Which... Is actually pretty hard to do.
Other than that, the other worry is worn bushings, which all transmissions have to worry about.
Though, I don't know about the year thing. Travis has a 95 and he's got a 42 in his truck. He bought a 47 to replace his though.
The 47 has some more useful upgrades like a non pressed in throw out bearing shaft.
On the 42, you have to disassemble the case, with the 47 you do not.
Some other upgrades and such as well.
If you look at the pictures, they are very similar, but they made some case modifications to them as it appears to me.
As for input torque. Look at cody and the other guys on here with sled pullers running this.
The biggest fear on a zf5 is snapping the input shaft. Which... Is actually pretty hard to do.
Other than that, the other worry is worn bushings, which all transmissions have to worry about.
Cargo Master
Joined: Feb 2010
Posts: 2,526
Likes: 6
From: College Station, TX
Here's some info directly from ZF. It's specific to the 42 but some can be implied and applied to the 47.
http://www.thedieselstop.com/faq/949...load/S5-42.pdf
http://www.thedieselstop.com/faq/949...load/S5-42.pdf
New User
Joined: Dec 2010
Posts: 1
Likes: 0
S5-42 and S5-47 not interchangable
These transmissions are not interchangable the 47 has an overall longer lengthcase from bellhousing to the tailshaft. Also if you would install a 42 where a 47 should have been originally equipped you will not get proper support between the pilot bearing and the input shaft. You will have only a 1/4 of insertion and the bearing and the shaft both have 1/8" of bevel ( to aid in insertion) so you have no real support and are doomed to mechanical failure. This I know from personal experience.
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New User
Joined: Mar 2007
Posts: 19
Likes: 0
From: Clovis
These transmissions are not interchangable the 47 has an overall longer lengthcase from bellhousing to the tailshaft. Also if you would install a 42 where a 47 should have been originally equipped you will not get proper support between the pilot bearing and the input shaft. You will have only a 1/4 of insertion and the bearing and the shaft both have 1/8" of bevel ( to aid in insertion) so you have no real support and are doomed to mechanical failure. This I know from personal experience.
I will avoid the 42 swap for sure then, it had been a gut thing not to go with it.
I haven't been able to do anything yet, needed a truck asap so had to defect to a 92 dodge (only decent truck I could find on short notice). I am still looking and these 47s are not easy unless I want to shell out $1800-2500, which I don't have right now. (plus extra new parts and install)
Thanks again.
Post Fiend
Joined: Nov 2003
Posts: 21,285
Likes: 16
From: Nutter Fort, WV
Hotshot
Joined: Jul 2008
Posts: 11,231
Likes: 130
From: Thomasville, GA
There are several people who have swapped the 42's onto a 95-97 7.3 with no problems, and seeing that it came stock in the 94.5 PSD and it is the same block as a 95-97 PSD I dont' see any problem with using the 42 on one of those engines as long as you use the proper flywheel/clutch for your application.
The driveshafts may be different lengths but any ZF5 from a '88-97 7.3 will fit the engine.
The driveshafts may be different lengths but any ZF5 from a '88-97 7.3 will fit the engine.
Hotshot
Joined: Jul 2008
Posts: 11,231
Likes: 130
From: Thomasville, GA
I've thought about it, but I'd rather keep a married t-case so I'm going to use the trans/t-case from my '88.
I just think that the np205 is one of the better factory t-cases out there, cast iron case and gear driven instead of aluminium and chain drive.
I just think that the np205 is one of the better factory t-cases out there, cast iron case and gear driven instead of aluminium and chain drive.
Freshman User
Joined: Dec 2004
Posts: 33
Likes: 0
NP205
Evan,
You can absolutely mount an NP205 (married version) to the ZF tranny. You just have to notch the transfer case mounting flange on the ZF. This is (relatively) commonly done in dentside trucks to retrofit an overdrive transmission where one wasn't available stock. If you search the 73-79 forum for zf swap, I'm sure you can find the info. The ZF case also has a boss for mounting the transfer case shift lever though you may have to fab up a linkage piece. Good luck!
You can absolutely mount an NP205 (married version) to the ZF tranny. You just have to notch the transfer case mounting flange on the ZF. This is (relatively) commonly done in dentside trucks to retrofit an overdrive transmission where one wasn't available stock. If you search the 73-79 forum for zf swap, I'm sure you can find the info. The ZF case also has a boss for mounting the transfer case shift lever though you may have to fab up a linkage piece. Good luck!