I am curious to find out if anyone has been successful at mating a 7.3 IDI or 6.9L diesel to a NP 435 trans. I have an old F600 that I am interested in switching over to diesel that already has the NP435. I'd like to keep the trans to save money and because it has a parking brake integrated into the *** end of it.

 

If you can find a T 19 four speed bell housing, the bell housing will bolt to the motor and the transmission should bolt to the bell housing.
The T 19 was the only transmission Ford used behind the diesel that had a seperate bell housing, and the diesel bolt pattern only fits 6.9 and 7.3 blocks.

T 19 and NP 435 both have the same bolt pattern if I remember right.

 

So that solves most of the problem. Now the question is which clutch/flywheel could be used. My NP435 has the bigger clutch that came behind the FT motors - I think it is 12".

 

There are 11 and 12 inch clutches out there, I can't remember for sure but I think I put a 12 in mine.

 

My neighbor put a 435 in his 86 6.9, used the stock T19 Bell housing.

 

You can use the 6.9 flywheel and simply bolt in the upgrade 12" setup. I did just that last winter, just that easy.

 

Dang, that sounds too easy..........SO , one last tidbit of information. Does the bell housing off of the 6.9L / T-19 combination use a manual or hydraulic clutch?

 

Itis set up hydraulic, but it pushes on an arm that could easily be made to work with a regular pushrod system.

 

Man, these things usually end up being more complicated. Thanks for all the advice.

 

Would the gear ratio of the np435 work with rmp range of the 6.9? If so I have one that was in my truck before the swap and wonder if it would help with mileage or the c6 as the auto never locks up and the manual would.

 

A manual vs an auto will always show an improvement in mileage, it is more a question how much and if it is worth the effort. The auto theoretically runs at 9/10:1, while the manual is obviously locked in at 1:1. If you have more slip than that on the auto, the converter is wearing out. If you were to have a lockup trans, it improves the converter slip to 1:1 like a manual, but yet, the manual still is a bit better.

 

Currently trying to mate my OBS 7.3 to the NP 435 in my Bus (B600)

 

Not sure how similar the FE/FT are to the 335/385 bell pattern, but the later can be drilled and used with the diesels. Top 2 holes are the same, middle need ovaled, and the bottoms need redrilled.

 

Shoot i judt realized this was the pre powerstroke thread i am trying to join and OBS 7.3 PSD to a NP435

 

For your intended purposes, theyre the same.