We have a 1990 with a straight 6. 4x4 with a 5 speed. The door tag appears to say that it has a zf s5-42 ( trans code w ). While the Internet is a wealth of knowledge, I'm also finding a bunch of conflicting information. This 90 4x4 f25@ has a straight 6 gasser and a five speed. I want to know if it will it on a 91 f250 7.3l idi.

Thanks in advance!

 

A big block "460" gasser bellhousing can be re-drilled to fit the diesel, but a small block bellhousing is way different. Short of putting a different main case on the small block internals there is no way to mount that ZF on a diesel.

 

I have a 4 speed on the 87 we want to put the 5 speed. If this one wont work, what will? Only a 460 5 spd, right? Will any 5 speed off a diesel 97 or earlier work?

 

You will want to try to find a 5 speed from an IDI truck (ZF S5-42, diesel housing) or from an early powerstroke (ZF S5-47). A gasser 460 ZF can be made to work, but you have to drill new (different location and larger) mounting holes in the bellhousing. Also be aware that the gasser version has different gear ratios, that you may or may not like depending on which axle gears you have and how you use your truck. The close ratio, diesel ZF with the diesel housing is going to be your easiest swap. When buying, look for input shaft play and the common crack that develops in the rear case webbing just forward of the 4x4 shift lever mount.

 

Awesome! Thanks so much!

 

ad u might need a new adtper for ut gv unit two

 

I have a 1986 F350, 6.9L T19 and GV overdrive. It has the BW1345 transfer case with the Gear Vendors rear case. The whole T case should bolt onto the ZF with no problems or new adapters needed.

 

This is what I have heard. If any one can confirm for sure that'd be great. Just to reiterate that I'm on the same page, joe. you're saying if I get a zf s5-47 it should bolt up in theory?

 

all borg warner 1356 transfer case have the same mounting pattern. it don't make any difference what it was on. if it had a 1356 case a 1356 will bolt on .
the ZF trans has an integral bellhousing. diesel trans will only bolt to diesel engine.
a gas trans will not work without redrilling and weakening the case.

 

... In fact most of Ford's "married" style transfer cases should mount up to to a ZF. Same mounting flange, shaft size and spline count. Not sure if your 1987 truck with the T19 would have come with a Borg Warner 1345 like my 1986, or a Borg Warner 1356 that was standard issue behind a ZF, but either way you should be fine to bolt ~your transfer case + GV behind a ZF 5. The ZF is almost exactly the same length as a T19 with bellhousing so you can use all your existing drive shafts as they are. Pretty straight forward, you just need the transmission and the right pressure plate/clutch disc to work with the ZF's larger input shaft.

 

Alright, well I hope I've found a good one. 5 spd (guy states its the zf5) came off a 94 7.3 idi. He says he thinks the clutch was having issues disengaging because reverse was hard to shift. Any sure fire ways to make sure the tranny is good if it isn't in the truck?

 

I'll second the seller in saying it is likely a clutch issue. Could also be the pilot bearing dragging. I had that issue on mine when I bought it. 1st was a pain, and reverse always was nasty grinding unless it popped it into 4th, then into reverse.

Should be a ZF if it came off a diesel, its the only 5 speed that came on diesels.

 

Awesome! We'll see how much we can get it for next then!