NP 435 swap questions

[Doug F]

Hey guys,

I got a 65,000 mile 1966 NP435 2wd trans that is absolutely MINT, with factory scribble and stenciling on it, to replace my who-knows-how-old-and-beaten NP435 in my 67 F100 4x4.

My questions is, again since it isn't detailed in the service manual, how does the output shaft of the trans mate to the tansfer case? My truck is at work and needs to be movable, so I will need to jump in, pull out the old trans and install the "new" one as quick as possible; does anyone have any tips or a how-to they are willing to offer up?

I got the gasket kits and I know the clutch is new and the transfer case is a new re-man.

Will I need to first remove the t-case from the trans and then pull the trans? Does the trans just pull straight back from the flywheel/clutch assy and then slide right back in?



Thanks again, your help has been invaluable!

[averagef250]

You will have to switch mainshafts in the transmissions. A 2wd mainshaft will not fit your transfer case.

[cep62]

Correct me if I'm wrong but the F100 tranny that goes to a D21 T case is a two wheel drive unit with a bolt on spline.
I think you can just bolt on the adapter and go.
Be careful taking it apart because the tail shaft can come out and you play 52 bearing pick up.

[Doug F]

Cep, that's what I heard and read too, according to the service manual illustrations, it looks as if the splined shaft "plugs" into the transfer case. Wish I had some REAL pics to go from! UGH!

Nothing I have seen or read mention a different shaft... But I will look into it.

Doug

[fordman]

the main shaft is longer inside of the 4wd trans so that the adapter covers the longer shaft.

[cep62]

the main shaft is longer inside of the 4wd trans so that the adapter covers the longer shaft.

But if i remember right the D21 uses a 2wd tranny with an adapter ,
that is held on by the nut that holds the yoke on.

Take off the yoke and tail housing and it should go on to the D21 adapter.

[fordman]

this is all i could find for the F100 http://www.fordification.com/tech/image ... kage02.jpg

[Doug F]

Looks as if 7024 is the piece that makes the trans hook up to the T-case. I have all that, since the trans in my truck is already a NP435 (2wd case) with 4wd.

So it looks like it should be a 1:1, unbolt and put back together type of swap.

[fordman]

keep this updated if it can be done or what has to be done to make it work. not only would it help out others i am thinking about doing the same thing sort of. i want to put a F600 5 speed in my truck.

[fordman]

let me look around the only one i knew about kind of got buried in the junkyard. i will try to unbury it. the last time i seen it it was till in the same place.

[Doug F]

Really? That'd be GREAT!

[Doug Comer]

I ithink if you use the 205 you will have to change the main shaft like Dustin said. If you use the Dana 21 I'd bet money you won't have to change it. Just my Good luck either way.

Doug

[71F100-390]

Did you have any luck? Just blew up the Dana 21 in our truck, need to figure out how we're going to replace/upgrade it.

So far it seems like the NP435 for a D21 has a square 2WD bolt pattern instead of the "A" pattern the later 4wd transmissions used, and a different spline count (10 vs 31). So, if you change the main shaft, you still have a bolt pattern problem?

Any updates?

[Doug F]

No updates yet...

From what I learned, you'd be best to find a trans and transfer case from a newer Bronco or F150 that is already to bolt in.
The shaft can be found and then you will need to find an extension housing which are HARD to find.

I am waiting to pull my cab to do a cab swap, before I pull the trans. It'll be much easier.

[FordTruck]

What about getting a divorced t-case?