How hard of a swap would it be to put a ZF5 into my 96 f350 4x4. It has the C6 and I want to get anything better than 8 MPG. I have done numerous tranny swaps before but never with a ZF and Im wondering is there anything special I need to know about them? I am looking for a ZF5 47 also not the 42 so If anyone knows were I can find a good one I would appreciate the help locating. Also, how much abuse can that tranny put up with behind a 460?

 

If you've done a tranny r&r before you can handle this. Don't forget to put in a pilot bushing. Here's a pic somebody sent me back when I did mine that shows what all you need, this helped me a lot:

 

I have an donor 4x4 truck that has an NP435 behind its 351m and I might use that instead since it's free. Do you think the it's worth it to buy a ZF5 and all the extras need to make it work? Or should I just use the 435 I have. I know I will need a few extras as well but the 435 swap will be much cheaper. What would you do?

 

If you are doing this to up your mileage then I would say you need the ZF5. The NP435 is just a 3-speed trans in everyday driving, at least the ZF would give you a 4-speed. What gears do you have in this truck? I am guessing 4.10 so you need the OD.

 

I am doing the swap because I want a heavy duty transmission behind my 460 that I can shift manually. I think the C6 is robbing power as well. My truck has 3.55 gears in it just like the truck the NP435 is coming out. I use to drive that truck and it was always in the right powerband with those axle gears so I figure my 96 F350 would be just fine with that tranny just a lot more fun.

 

If you've got a donor truck with everything you need then go for it - you can always swap in a ZF5 later on if you run across one.

 

You will need a hydro clutch bellhousing. Other than that it's an almost drect swap. You can't use the bell from the 351m, even though they are the same pattern. I put a T18 in mine not too long ago, and it's ok, but I'm picking up a beater later today for the ZF5.

 

I have swapped in an np435 to a 460 before and never needed a different bellhousing as long as the tranny came off a truck with a 351m/400. The only other part needed are a externally balanced 79-later flywheel and a different rear driveshaft.

I have been told before that a C6 that was behind a 6.9 diesel can't be used behind a 460, and with some tweeking I made it fit.

 

There are two different types of bellhousing for a given engine/transmission application, one is for hydraulic clutches and the other is for mechanical linkage clutches. They are not interchangeable and if the OP wants to retain his hydraulic clutch he has to have the correct bellhousing.

 

The issue with the NP435 from behind the 351M is the input shaft. The 351M/400 needed a longer input shaft to put it in the correct position with the flywheel, where it will be a problem with the 460 as the fly wheel sticks into the bell house a bit further than the 351M/400. I dont remember what the length difference is but it is significant enough to be a consideration for using the NP435 from behind the 351M/400 block on a 460.

 

Well the truck the np435 might go into has no clutch and the old truck has the manual linkage so I will end up using the manual linkage from the 78 on the 96.