ZF 4hp22 tail housing swap? E28 to e23.

[Jviolinman]

I'm looking at a 1985 ZF 4hp22 Transmission but I think its from a e28. The bellhousing is different plus the output shaft has a about half an inch extra length to it. Will the output shaft swap form my original transmission work or best to find a new transmission? Thanks!

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[Kenneth1948]

I hate to see a post without a reply so I will let you know my experiences.
Firstly, Mine is an '84 733 with the hydraulic shift, old fashioned! no electronic connection ZF 4hp22H. I think your '85 probably has the ZF 4hp22EH. So, make sure the transmission you plan to install has the correct connector plug. I don't know for sure, I do know the H transmission was only used for a couple of years on the 7 series E23. It was used for longer on the 325, I have no idea on the 5 series E28.
I did two swaps. One from a 325. This was the easiest. The bell housing swap was easy. Had to change the output flange, can't remember about the rear housing, mounts maybe? and the kick-down cable will fit, but much neater to change the cable. Transmission worked fine but also turned out to be well worn.

The other swap was from an earlier 533. Likewise with bell housing but output flange shaft was too long and had to take it to a machine shop and remove about 1/2 inch off the end to make the shaft the right length. This worked fine but the problem was the older 533 has a different flange connection with no spiggot. I just aligned it as best I could and installed the flange bolts real tight! with intentions of figuring out something better in the future. The 533 transmission is excellent but ran into other troubles with the car.
So, I can't tell from the photos exactly what you're dealing with with the output shaft and flange. I can see the spiggot on the end of the shaft so at least you don't have that problem. You may be able to modify the shaft and/or flange. Feel free to ask if there's anything I can help you with.

Finally, are you sure the E28 tranny is any good? it looks pretty old. It's straight forward to change them but still takes time and costs money. As I found out, the guy I bought the 325 tranny from had not "driven and tested" it as he said! Good luck, John Kenneth