I am working on a frame off rest-mod with my boy. The truck has a c6 from the factory but my son wants to shift gears. Does anyone know if the zf5 bell housing from a non turbo 7.3 will bolt to the 400m? Since it is a true high boy with divorced transfer case I should be able to use a zf5 out of a 2wd as far as I know. If she will not bolt up is there a source for an adapter plate that you would recommend?

 

The quick answer is yes and no

In reality it will not bolt up, most of the bolt holes and the alignment pins do not match up. Now that being said it is possible to re-drill the trans case. The upper two holes are the same for the 400/460 pattern and the 7.3 pattern. Using those holes you can align everything up and drill the lower holes and the guide pins.

I would not recommend this though because it's very hard to get everything perfect.

It would be much easier to sell the 7.3 zf5 and buy a 460 zf5.

One note about the zf5 and the 400 is that you will need a flywheel spacer or a throw out bearing spacer to get the input shaft and the flywheel to match up correctly.

 

Agreed. The 7.3 won't bolt up, but the 460's will. Here's my thread on making the spacer, which has to be highly accurate since any error on it is magnified at the edge of the flywheel.

Mine works really well and I love the ZF. But when Dad's truck goes back together it'll have a PMGR starter from a 460 bolted in. That will allow the ring gear on the flywheel to remain in the factory position.

My drawings have been used by at least one other FTEer to have a machinist make the spacer, and his project turned out well also. At one point I think he had extra spacers made up for others to buy, so I can chase him down to find the status of them if you'd like.

 

Gary, what is a PMGR starter? Also what clutch disk did you use? My ZF has a 10 spline 1.25" input shaft and the only disk I can find are 12.25". The pressure plate for the 400 will only take a 12" disk.

 

PMGR = Permanent Magnet Gear Reduction. The starters are much smaller, pull less current, and have more torque.

As for the clutch, I went with the Saks 11" from the table in this post. Hope that helps.