NP435 variations?

Hi All,

One for blokes have tooled around over the years with New Process 435 transmissions.
I have a couple of them here, one in a rebuild project, t'other I got off a bloke for around the cost of a carton of universal tender!

One in project vehicle has no tags, but casting No. G-96391-P. Came from behind a 240/300 Ford inline six, has clock face with the number "70" and a few dots at 4 0'clock, so I am assuming it came from the New Process (Chrysler) plant in April 1970?

Spare again has no tag, but casting No.
G-96391-S. Both seem to be identical, think this one MAY have been from behind a V8, but not sure. Rotate the input shaft by hand, comes out at what I would guess is stock ratios of 6.69/3.34/1.79/1.00:1. This one also has a clock face with the numbers "68" stamped in it, so again, assume it was produced in 1968. Would the difference in the last letter designate anything in particular? Possibly different factories? The only anomaly I can find so far is for some strange reason, the gear shift levers are NOT interchangeable! Later model has a deeper groove cut in the sides of the ball socket where it is retained by the two pivot pins and held down by the spring and retaining cup. Try swapping them back the other way, late model stick flops about in earlier receiver!

I know it is a bit of a long shot, and can't really check the later one (input spline count VS output spline count) as it is installed in the vehicle. Would they both be the same ratio transmissions i.e. in-line six and V8? Have asked a few questions on other forums and so far no replies. If 1968 and IS from a V8, what size and series did Ford run in that year, 1968? I would have thought that they would simply have used different diff ratios?

Part two of the question is a little different, have heard that at one stage, just about all the light truck manufacturers used the NP435 in varying guises. Certainly Ford were a major user, as were Dodge, I-H and have even heard of Chevy running them before using their own Muncie SM420 as well as later SM460. Seems in the States and Canada they are still popular, but they seem to prefer swapping the gearsets from either a Dodge or Chevy NP435 because of a better spread of ratios. Again, some say that the Dodge version uses a different spline count on the input shaft and they avoid them. Has anyone ever tinkered around with them, as far as I can work out, the ideal box is to use the Ford gearcase and swap in the Chevy gearsets, if you can find one in good nick. I-H used them a lot, but have heard they are an entirely different gearcase.

The standard Ford version seem to be the best bet for spare parts if needed, probably because they used them for so long over so many models. But the huge step between gears could have been better, more like Dodge and Chevy. Would be interested in others thoughts on these transmissions. Not really interested in the pros and cons of NP435 versus Warner Gears T98/T18/T19. It would be akin to Holden vs Ford, you would argue a case for either for the rest of your life!

Dave,

There were a couple of different ratio sets in the Ford boxes, but not really sure if they specified one or the other for v8 versus 6cyl. The box in my f100 is the 6-point-something from behind a 240, and is doing very nicely with the 302 clevo.

As far as I know the difference between the ford/chev/dodge boxes - besides ratios - is input shaft spline/length, and also the diameter of the front bearing carrier.

As for the borgwarner boxes, you're right- you could argue all day except to say they offer a different set of ratios again, and the T19 has synchro on first.

HI Willweld,
Thanks for that info. Couple quick questions for you, you said that your NP435 came from behind the inline 240, and now running quite well behind a 302 Clevo, did you have to change the actual bellhousing? Or, are they interchangeable? Do you know if the 302 Windsor uses the same pattern? Also, final drive ratios would have a lot to do with road speeds and gaps between gears. In my application, my ORIGINAL box came from behind an F350 running a 4.88:1 diff with 31 X 15 wheels. On the project vehicle I am running the same size wheel, but moved up to a 3.73:1 diff ratio, quite a large step as you will appreciate. I as yet have not tried this combination on the road (still rebuilding), but am a little concerned about the steps between gears will be even more noticable. However the project vehicle is a lot lighter in tare weight so it may not be an issue. Given that I am still using the inline six, so for my use, huge horsepower is not wanted, but bottom end torque and good driveability is more desirable.

I was unaware of Ford using different ratios in their NP435 instillation's. I know that Dodge NP435's are still about, having the better spread of gear ratios, 4.something first gear.

Ideally, if I could somehow fit the Dodge innards in the Ford casing (be a bit tricky unless I have the input shaft machined) it would possibly be a better combination. Don't really want to go via the way of having a bellhousing machined up to fit a Dodge box onto a Ford engine. Been down a similar road before and it really became an expensive hassle. I suppose it is the old story, nothing is impossible if you have the time, patience and a deep pocket!

Thanks, Dave

years ago i was going to put a 351w in a D series ford (it had the 300ci 6cyl) from memory the bellhousing & flywheel is the same ..( needless to say the 240-300ci 6cyl & the 302-351w all started life as a Canadian motor) there is still some good "hot up gear" avail stateside for the 240-300ci 6cyl as well

Hi Kenny,
Thanks for that, answered one part of my question(s).
I am guessing from your nom-de-plume that you are a bit of a Chrysler/Dodge fan? If so, ever had anything to do with those early Dodge NP435 (non-synchro !st) gearboxes?
As opposed to the NP445 which I have been led to understand are virtually the same box but synchro on first, and also a different ratio?

Just from having a bit of a squiz on the net, it seems that there are still parts available for the early Dodge NP's, whereas the GM version are getting scarce.

As far as performance parts for the Ford inline 240/300, I got hold of a full gasket kit off fee-bay. About the only thing I was looking for was an extractor set , so as to clear the starter motor/firewall in the project vehicle. Worst comes to worse, a bloke in Ballarat can make me a set from scratch, just have to wait until I finish what I'm doing before taking it down.

Thanks again, Dave

Dave,

I found a chart listing the ratios for the different boxes. Here goes...


1st 2nd 3rd 4th Rev.
NP435A (Dodge, GM) 4.56 2.28 1.31 1.00 5.64
NP435L (Ford, Dodge, GM) 6.68 3.34 1.66 1.0 8.26
NP435D (GM) 4.90 2.29 1.19 1.00 6.06
NP435E (Ford) 6.68 3.34 1.74 1.00 8.26

As for putting the 6cyl box behind the v8- the bell housings are interchangeable, but you must use the v8 flywheel because they are balanced differently, even though the 6cyl one will fit.

Thanks Wilweld!
Have copied that ratio chart, there's one there I was unaware of, two different Ford listings for 3rd gear 1.74 VS 1.76:1.

Also, that flywheel change, although it won't affect me, as I'll be sticking with the inline six and only changing the gearbox itself if necessary, I'm glad you noted it. Years ago I stuffed a 343 Rambler into a Jeep which was auto, had a devils own job getting a manual flywheel and was lucky enough to be able to utilise a six cylinder, can't remember exactly, but something to do with one being externally balanced, the other internally so.

Cheers, Dave

Hi Kenny,
Thanks for that, answered one part of my question(s).
I am guessing from your nom-de-plume that you are a bit of a Chrysler/Dodge fan? If so, ever had anything to do with those early Dodge NP435 (non-synchro !st) gearboxes?
As opposed to the NP445 which I have been led to understand are virtually the same box but synchro on first, and also a different ratio?

Just from having a bit of a squiz on the net, it seems that there are still parts available for the early Dodge NP's, whereas the GM version are getting scarce.

As far as performance parts for the Ford inline 240/300, I got hold of a full gasket kit off fee-bay. About the only thing I was looking for was an extractor set , so as to clear the starter motor/firewall in the project vehicle. Worst comes to worse, a bloke in Ballarat can make me a set from scratch, just have to wait until I finish what I'm doing before taking it down.

Thanks again, Dave

here is Hitech headers part number for extractors for the 240-300ci into the d series truck HTH058
& for your induction Clifford performance Stateside is the go www.mustangandfords.com/how-to/engine/52...ne/photo-gallery/#13

as for the New Process gearboxes ive really only played around with the "540"which is a direct top gear 5 speed

cheers ken

Thanks Kenny,
Have sent an email to Hitech as to availability. As I have the two piece manifold, may have to leave inlet as is because of height restrictions with carby on project vehicle.

Cheers, Dave

I have 3 x different boxes, a 1968 , a 1972 and a 1975
The '68 came as a spare so not sure what it was out of, but I did notice the front bearing retainer has no seal in it, just a spiral groove for oil return.
Both the other boxes have an oil seal fitted in there.
One is behind a 318V8 Dodge, the other behind a 345 V8 Inter.
All the input shafts are different, but output ends are the same, ratios are the same too.
I've not tried interchanging shifters as no need to do that.