Odd ball NP435??!!

[Bronco_74]

I am currently installing a NP435 into my 74 with the 200. I ran across an interesting situation with the input shaft on the NP435. From the information I can find, the Ford and GM versions of the NP435 had a 6.5 in front input shaft with 10 splines. The front bearing retainer plate on Ford were 4.85 in diameter. I'm not sure on the GM ones.

I have a NP435 that has a 7.5 in front input shaft, a front retainer plate that is 5.25 in diameter, and a 10 spline shaft. The Ford belling housing is only able to accept a 4.85 in diameter plate. I did have to replace the the rear output shaft in order to get the spud shaft to mate up. As you can see, my NP435 will not bolt up to my bell housing because my retainer plate is too wide. I'll check in the morning to see if I have a roller or taper bearing on the front input shaft. Edit: I have the taper bearing setup.

I am trying to figure out what NP435 it is? Does anyone know if I can use the front retainer plate on the 6 cyl trans to replace the NP435?

 

[Quick & Dirty]

The NP435 was also used in medium duty trucks, with different inputs and outputs than the light trucks, some have the parking brake on the output.


This one is from a 70's Ford school bus;

 

[thepunisher]

I know for a fact they where in early 70's single axle dump trucks. Also cab and chassis trucks from the early 70's.

 

[DirtDonk]

...I did have to replace the the rear output shaft in order to get the spud shaft to mate up.

In other words, you've put good money into it and don't want it to turn into bad? I'm no 435 expert, but I'm thinking you're out of luck on the front retainer swap.
And maybe even the shaft? It may have 10 splines, but did you compare the diameter too? Are you able to slip the clutch plate over the splines for a good fit? If so, you've still got that extra length in the way.
Either way, it sounds like it's not just the front cover/retainer, but a new input shaft too. If that's possible.


Does anyone know if I can use the front retainer plate on the 6 cyl trans to replace the NP435?

Unless somehow the bolt pattern is by some stretch the same between the two, I don't see any way to bolt one to the other. I'm thinking it's to support the larger bearing, and not just a different size to register into a different sized hole in a bell-housing. But I'd love to be wrong on that score.

Maybe someone can measure their bolt spacing and you can compare.
Is that your transmission in the pic Quick n Dirty? If so, can you measure your front bearing retainer? Looks like a big one from here, but if not, it might give some comparisons Bronco_74 can work with.

Good luck. And welcome to CB.com if you haven't been already. Sorry to hear that the frustrating world of swapping parts bit you so early in the game.

Paul

 

[Bronco_74]

Well thanks for the welcome.

So the front bearing retainer plates are definately not interchangeable for future reference. The 6 cylinder transmission has a roller bearing for the front shaft while the NP435 is a taper bearing. No luck there.

If anyone has a spare NP435 sitting around, would you mind checking out these dimensions for me? If I was a contributor, I would upload the pictures. Instead I'll try to describe these measurements as best as I can. These are the dimensions for the front bearing retainer plate bolt hole spacing. I measured from outside edge to outside edge of each hole using a caliper. I measured these distances on the plate itself and not on the transmission. Across the top 2 holes, I got 3.050 inches. Passenger side holes, I got 3.448 inches. Drivers side holes, I got 3.434 inches. Bottom side holes, I got 3.327 inches. Outside diameter of the plate, I got 5.123 inches. Outside diameter of the part that inserts into the transmission (part that holds the bearing race), I got 3.541 inches. Inside diameter of the part that holds the bearing race, I got 2.842 inches.

I am basically trying to decide if I can just find a different front shaft and retainer plate, or if I need to completely get a different transmission.

 

[bax]

With the ten spline input I believe you are looking at a SM465 a chevy based unit.

 

[langester]

I looked at mine this morning , its still sitting in the garage. I didn't remove the retainer but here are the other measurements.

Top holes 2.750
bottom 3.050
drivers 3.150
pass. 3.250

O.D. 4.850

Hope it helps!

 

[langester]

I forgot to mention my measurements are center to center on the bolts.

 

[Bronco_74]

I looked at mine this morning , its still sitting in the garage. I didn't remove the retainer but here are the other measurements.

Top holes 2.750
bottom 3.050
drivers 3.150
pass. 3.250

O.D. 4.850

Hope it helps!

Hey thanks! This does help. After rechecking from the center of the bolt holes, this looks to be a perfect match! Now I just have to figure out if the bearing race and the part of the plate that inserts into the tranny is the same. Would you be able to measure two last things for me Langester? Could you measure the overall length of your input shaft from the mounting surface of the tranny? Also the length of the splines/pilot bearing surface that sticks out beyond the end of the plate shaft(if that makes sense)?

With the ten spline input I believe you are looking at a SM465 a chevy based unit.

Is the SM465 just a NP435 that was produced for GM? The top aluminum cover on mine does have the NP stamp on it if that helps.

 

[DirtDonk]

Completely different transmissions. The common three, the 435, the SM465 and SM420 were often found in the boneyards back in the day. The last two were mostly GM Muncie units, while our trans-of-choice was the New Process more likely to be found in the Fords.
Not sure about bax's comment about the 10 spline thing, since I think ours were too. Just a different diameter, like our 1 1/8" vs 1 1/4 for some. That's why I was asking about the diameter of the splines earlier too.
But he's a pretty smart feller, so I'll defer to him on that last bit until I can get into one of my clutch catalogs. Easy to find those listings in places like the Centerforce book and such. Better than this new fangled internet thing where supposedly you can find stuff instantaneous like.

Paul

 

[langester]

Here are some measurements and some pics.


overall length from face of transmission to tip of input shaft 6.5
tip of bearing retainer to tip of input 2.5
end of splines to tip of input where pilot bearing is about .875

Need anymore let me know.

 

[Deano]

I have driven a EB with a 200 I6 with np435 in it it was great. they should of come from the factory that way.

 

[broncnaz]

GM typically had a smaller or larger front bearing retainer than the Ford bearing retainer. Supposedly the GM NP435 only came with a roller bearing type input shaft bearing. Where the ford had a tapered one. Also the GM version didnt have as low of a first gear as the Ford and dodge versions.
Ford used a 1 1/16" 10 spline input gm used a 1 1/8" 10 spline input. The ford big truck ones had a larger input 1 3/8" and a larger diameter inputshaft retainer along those lines the output shaft is usually larger as well
But as was said ford did use a 7.5 inputshaft usually on pre 1965 trucks not sure about later big trucks but thats also a possibility. I beleive those early ones also used a 4.675 bearing retainer vs the later standard 4.85
All in all Id take your tranny to a junkyard and see if you can swap it for the correct one. It will probably be a lot easier overall than trying to modify what you have to work.

 

[bax]

The SM had a cast iron top so im wrong.

 

[R.P. Coltrane]

Got a machine shop buddy? Because it sounds like to use that trans as-is you're going to need a one inch spacer plate to make up for the extra input length. At that point it's no big deal to put 2 different centering diameters on the spacer plate. However the tailshaft and shifter are moving back one inch too, and that could be a headache (or not)

You could also turn down the bearing retainer and make it the correct diameter. Shafts can be cut and a new pilot bearing surface turned.

At some point you have to question the wisdom of that kind of stuff when the correct parts are out there. However, as mentioned, if you have a machine shop buddy that guy might make things easier than hunting down the right parts.......

good luck

 

[Bronco_74]

GM typically had a smaller or larger front bearing retainer than the Ford bearing retainer. Supposedly the GM NP435 only came with a roller bearing type input shaft bearing. Where the ford had a tapered one. Also the GM version didnt have as low of a first gear as the Ford and dodge versions.
Ford used a 1 1/16" 10 spline input gm used a 1 1/8" 10 spline input. The ford big truck ones had a larger input 1 3/8" and a larger diameter inputshaft retainer along those lines the output shaft is usually larger as well
But as was said ford did use a 7.5 inputshaft usually on pre 1965 trucks not sure about later big trucks but thats also a possibility. I beleive those early ones also used a 4.675 bearing retainer vs the later standard 4.85
All in all Id take your tranny to a junkyard and see if you can swap it for the correct one. It will probably be a lot easier overall than trying to modify what you have to work.

I measured my input shaft. It is 1 1/16" with 10 splines. 7.5" shaft and 5.123" bearing retainer. Yeah I'm going to have to try and find a donor. I don't want to get rid of mine quite yet though. I have a fair amount invested into it already. My fault because I never thought to measure the front input. It looked right, had the right spline count, and was free. I had it rebuilt and put in a new output shaft. That's the only reason I'm still messing with it. Worst case I figure I'll get another NP435 and switch out the internals.

Here are some measurements and some pics.


overall length from face of transmission to tip of input shaft 6.5
tip of bearing retainer to tip of input 2.5
end of splines to tip of input where pilot bearing is about .875

Need anymore let me know.

Hey thanks for measurements again! I was trying to compare all aspects of my front input.

Got a machine shop buddy? Because it sounds like to use that trans as-is you're going to need a one inch spacer plate to make up for the extra input length. At that point it's no big deal to put 2 different centering diameters on the spacer plate. However the tailshaft and shifter are moving back one inch too, and that could be a headache (or not)

You could also turn down the bearing retainer and make it the correct diameter. Shafts can be cut and a new pilot bearing surface turned.

At some point you have to question the wisdom of that kind of stuff when the correct parts are out there. However, as mentioned, if you have a machine shop buddy that guy might make things easier than hunting down the right parts.......

good luck

I don't have a buddy who does machining unfortunately. Would be nice to have a buddy like that though someday.