NP435 Repair Manual

[18Z]

Does anyone have a PDF copy of the GM Truck Unit Repair Manual X-7B-08B, Transmission New Process 4 Speed Model 435. I am about to rebuild one. I have the 18 page ford one and the 10 page chevy one out of the chassis manual but the one above is a 26 page one that I can't find.

Thanks
Kirk

[Willys_MB]

I also have this transmission. There really isn't a lot of information out there. Everybody says there is, but actually finding information is challenging. Have you looked over this website?
http://www.novak-adapt.com/knowledge...s/manual/np435

[18Z]

I have checked that website, I found the manual I was looking for on a Ford forum tonight, but thanks for the info.

[Willys_MB]

Care to share the manual on here?

[El Dorado Jim]

I have never heard of the New Process 435 4 spd trans...what year is it? I have heard of the SM420 and the SM 465, I have the SM465 in my 72

[WorkinLonghorn]

Here you go Jim; I have one in my truck. Had a SM465 in my last '69 and like this 435 a LOT better. -BA

http://www.novak-adapt.com/knowledge...s/manual/np435

[El Dorado Jim]

Originally Posted by WorkinLonghorn

Here you go Jim; I have one in my truck. Had a SM465 in my last '69 and like this 435 a LOT better. -BA

http://www.novak-adapt.com/knowledge...s/manual/np435

thanks, I didnt know they put these in Chevys, I have seen them in Fords, didnt know who they were made by

[Bob B.]

The NP435GA transmission was the 4 speed manual used with the GMC 305 and 351 V-6's in 4X2 trucks, and was also offered as an option in other '67-'72 Chevy and GMC trucks. It's a heavy duty unit but unlike the SM420 and SM465 it is a close ratio transmission that does not have a 'granny' low ratio 1st. gear. They even use a different knob, marked 1-2-3-4 unlike the L-1-2-3 knob sometimes used on the Muncie transmissions. Ford, Dodge, and IH used other wide ratio versions of the 435 that did have a 'granny' 1st. gear.

My '67 has a 435GA, and I normally use 1st. gear when driving. 1st. gear is a much higher 4.56:1 than the 7.05:1 low gear of a Muncie. The GMC V-6's made so much torque off idle and at low r.p.m.'s a very low 1st. gear was not necessary.

Some '67-'72 Chevy and GMC sales literature lists the 435GA as a 'close ratio 4 speed'. I think over the years many mistakenly believed this referred to the Muncie M21 'Rock Crusher', which was never offered in any trucks other than the El Camino.

The Ford NP 435 shop manual should be fine, the other differences between the regular 435 and 435GA are minor.

[Willys_MB]

Originally Posted by Bob B.

The NP435GA transmission was the 4 speed manual used with the GMC 305 and 351 V-6's in 4X2 trucks, and was also offered as an option in other '67-'72 Chevy and GMC trucks. It's a heavy duty unit but unlike the SM420 and SM465 it is a close ratio transmission that does not have a 'granny' low ratio 1st. gear. They even use a different knob, marked 1-2-3-4 unlike the L-1-2-3 knob sometimes used on the Muncie transmissions. Ford, Dodge, and IH used other wide ratio versions of the 435 that did have a 'granny' 1st. gear.

My '67 has a 435GA, and I normally use 1st. gear when driving. 1st. gear is a much higher 4.56:1 than the 7.05:1 low gear of a Muncie. The GMC V-6's made so much torque off idle and at low r.p.m.'s a very low 1st. gear was not necessary.

Some '67-'72 Chevy and GMC sales literature lists the 435GA as a 'close ratio 4 speed'. I think over the years many mistakenly believed this referred to the Muncie M21 'Rock Crusher', which was never offered in any trucks other than the El Camino.

The Ford NP 435 shop manual should be fine, the other differences between the regular 435 and 435GA are minor.

That's interesting. Mine definitely has a granny gear. Max speed of ~5 mph. I rarely use it and always start in second gear. I wonder if that's the difference between the NP435 and NP435GA...

[Willys_MB]

The NP435 was a Chrysler product. My understanding was that it came standard in GMC, but was an option in Chevy trucks, but that could be wrong. It's a standard 4 on the floor with a granny gear. I just had mine apart and I was surprised at the shape it was in. The tranny was dated 1967 and in my 1968 truck. I'm pretty happy with it, so it's staying!

[A1971Blazer]

A lot of the 435s that are in Ford trucks have extra ears cast on the front of the housing that can be drilled to fit a GM bellhousing...the 435 is a tough transmission much like the 465 Muncie....
I have a Ford435 with a driver drop NP205 that I'm saving....for a future use....?

[Dave64]

Hi Guys,
Recent newcomer to your forums, live down under (Australia) and have not long taken possession of a 1975 C30 LWB dual rear wheels/ SBC 350/ SM465/ 14 bolt rear. In reasonable nick for over here, few spots of rust but otherwise not too shabby.

I too have been following (with interest) for a while now, the NP435 saga, re Chev/GMC 1968-1972 that came out with the 435 GA transmission.
Seems to be quite a bit of dissension, not only here but on other forums, just what, where and when they were used. I am referring to the "GA" version of the NP435, NOT the common as wide ratio "granny" gear version, just about anybody and everybody used that one.

Just to put my two cents worth in, yes, New Process was owned by the Chrysler Corporation and made many different versions of transmissions for many different light truck makers. Wasn't unusual at the time, apparently an autonomous division of a major corporation was still supposed to generate revenue. And in transmissions, New Process DID have a top notch product.

Onto the "Close Ratio" NP435 GA, which I read as having been the std 4 speed HD transmission offered between 68-72. Again, going by my research, this transmission was a 4.56:1 FIRST, 2.28:1 SECOND, 1.41:1 Third, 1.00:1 FOURTH. If my info is correct, COULD have been installed in both GMC as well as some Chevvy, from 250-292 sixes/ 307-350 SBC etc, also SOME V6 engines.
Again, this is only what I read both here and on other forums.

New Process also produced what they called the NP4350 transmission, (often referred to as the NP445) ALL-SYNCHRO CLOSE RATIO trans, I have one here in my garage, externally very similar to the std NP casing except an inch longer, has two extra "ears" on the front casing, at first glance easy to confuse the two.
Whether this is similar to the NP435GA (other than identical ratios), I have been unable to determine. I had written away to many forums, transmission "experts", parts warehouses trying to locate an input shaft and about the only thing I'm getting back is they are "obsolete, can't get parts anymore" etc etc. They must have made thousands of these transmissions at the time, can't have all been sent to China to convert to cutlery. I don't consider a 50 year old vehicle or parts all that old, just a matter of keep hunting down leads.

I realise the original post goes back quite some time, but somebody still seems to be wanting info other than myself. I find it hard to believe that if they were as they say, defunct, that you would sell the vehicle , drop an auto in, (or a SM465) without trying to chase down parts.
Would be interested in what others views are.
Cheers, Dave64

[WorkinLonghorn]

Hey, welcome to the forums.

My GMC came with the NP435 and I prefer it very much over the 465. The 3d gear is actually 1.31 (you posted "1.41" -probly a typo). It was an option on these trucks but only on the C/20 or C2500 GMC (at least in my year, 1969) as option code M28. The throws are short and very snappy. Standard transmission was three "on the tree".

[jocko]

NP435 Parts for anyone looking

[Wrenchbender Ret]

Back in the 60,s I worked for a truck leasing fleet. We had a few of the 435 NP trans some in Dodges & GMC,s. We had a lot of trouble with them. They had weird syncros
in them. They would bust up & were expensive to buy new ones. Also the aluminum covers would crack. I sure wouldn't want one.
George

[Dave64]

Thanks for the prompt replies, Men.
Longhorn, you are spot on, must have hit the wrong button and slipped through, is indeed 1.31:1 3rd gear.

Jocko, alraedy been onto that guy, recently sent me a small parts kit for an NP435, reasonably priced coming all the way from the states.
Unfortunately, didn't have a Chev NP435 GA input shaft, had Dodge and/or Ford but no Chev/GMC.

Wrenchbender, that surprises me a bit. We had them over here in both Ford and Dodge guises, locally assembled with imported components of course, both makers had them installed for the best part of twenty odd years, albeit they were the 6.68 first gear versions. I have had half a dozen here at different times, even an Inter Harvester model, personally I found them quite a robust box, easy to work on as long as you got your bearing pre loads spot on otherwise they were reluctant to shift properly.

I even tinkered with the input ratios on one I have just finished rebuilding, made an overdrive box out of it, seemed to test out OK on the bench at least.

Suppose it's like a lot of things we buy and try, what one guy prefers, another won't have as a gift.
Cheers, Dave64

[WorkinLonghorn]

Doesn't prove anything but the one in my truck is 50+ years old and hauled around a 2000 Lb Camper for it's first 28 years and then became my work truck hauling gravel, sand, mulch, wood etc and it's never had a thing done to it. Couple of the syncros are starting to go. I can imagine how those lease trucks were driven to break a NP435, one of the toughest transmissions ever made for light duty.

[Dave64]

WorkingLonghorn,
Just reading your earlier post, you say you have nearly fifty years out of your NP435GA and you also add that a couple of synchros are starting to go. If I got a fifty year run out of one I'd be more than happy.
As I said earlier, I have about half a dozen (just the straight NP435 with 6.68:1 first) here and picked the eyes out of all of them to come up with two decent boxes and got away with re-racing them and putting new gaskets and shims in.

Have you ever tried to get parts for your NP435GA??
I am not familiar with that Chev variation, so don't know if the case external sizes are the same as the common old New process type. I also have the NP4350 (or NP445) which although having many common components (bearings, seals, gaskets etc), is about one and a half inches longer in the case and internal, so not interchangeable.

I have been hunting around for an input shaft for some time now, to suit the same box as you have, but seem to be scarce.

Also seems to be some dissension as to the actual tooth count of the input shaft to cluster gear.
According to Hemmings they were a TWENTY ONE tooth input shaft, whereas I came up with a 22/38 combo on the cluster.

Standard 6.68:1 first gear in all the ones I have here are 17/43 input to cluster count.
Would either you or someone else following this post be able to confirm this?

Funny thing is, over here in all our literature by any of the manufacturers, the 4.56:1 ratio first gear version was OPTIONAL, but as yet I have been unable to find anyone on our forums here who has ever actually had the close ratio version.

Have tried quite a lot of people over your way looking for a Chev NP435GA input shaft, so far unsuccessfully.

One other thing was I have been told by quite a few others that the Chevy input shaft housing ran a different type of roller race and seal to the other types of 435's. I downloaded a workshop manual online and it is telling me that the larger inch and a half diameter input did indeed run a roller race, yet the smaller inch and an eighth was actually a tapered roller bearing.

So, somewhere, somehow wires got crossed.
Still doesn't help me to find the correct input shaft.
Cheers, Dave64

[WorkinLonghorn]

Hello Dave64. Sorry to be of no help but I've never had my NP435 out to look at it and never needed to know much about it. I've read about the different bearings, roller or taper. The Chevy/GM one had the roller and 10 spline input according to these guys;

https://www.novak-adapt.com/knowledg.../manual/np435/

I would give them a call. Wish I could be of more help. Brian

[Eric Johnson]

My late production 67 GMC 3/4 has a 435GA. It does have a granny gear and 4 speed inscribed knob... Fun to drive tranny!

[Dave64]

Guys,
I have here on the computer, a download of article X-7B-08B (dated Sept 1978) which is a Chev/GMC publication which designates the close ratio first gear as NP435GA, ratios given as first gear 4.56:1.

Eric, quoted "My late production 67 GMC 3/4 has a 435GA. It does have a granny gear and 4 speed inscribed knob... Fun to drive tranny!"

I suppose it will depend on what the individual calls a "Granny Gear", I have always taken that to mean the deep first gear 6.68:1, the very common ratio.

Don't wish to get into a slanging match with anyone, but even the Novak site makes no mention of an NP435GA, it also states that ALL the Chev/GMC input shafts were of the roller race type. Yet the publication I quoted above tells me that there were TWO different diameter inputs, as well as TWO different bearing types used, 2 at tapered roller type, the other larger shaft a roller race type.

To further muddy the waters, I went onto the Hemmings site and they are telling me that,"NP435s used three different input shafts on 1966-’72 GM trucks:

GM# 2462235- 1-1/8 inch X 10 spline 21 small teeth, 17 large, 9-1/8-inch length, New Process# WT-291-16B
GM# 3858831- 1-1/2-inch X 10 spline 21 small teeth, 17 large, 10-5/32-inch length, New Process# WT-291-16H
GM# 2942337- 1-1/8-inch X 10 spline 21 small teeth, 21 large 9-1/8-inch length, New Process# WT-291-16J

the only finer spline input shaft is for 1969-’85 Dodge #2909382- 1-inch X 23-spline 21 small teeth, 17 large, 10-7/8-inch length, New Process# WT-291-16Q, however, this input uses a tapered bearing, whereas the other three used roller ball bearing. We see nothing in a 22-spline.

Going by them, (Hemmings), the two shafts with the 17 large teeth would be correct for the 6.68:1 FIRST gear both large and small diameter, but the 21 tooth version(4.56:1) doesn't match what I have here and been advised

So, somewhere along the line there is some misleading info being quoted.
I know it may sound like I'm beating the subject to death, but in trying to find even a second hand input shaft, I have to positively identify it.
I do know for certain that the 4.56:1 ratio box I have here has a TWENTY-TWO tooth input shaft, I have the box sitting on the bench, took the input shaft out and counted them THREE times, definitely TWENTY-TWO teeth!
Dave64

[WorkinLonghorn]

I would call Novak in the above link and ask to talk to the NP435 specialist.

As for "granny" first gear; It depends on the differential gearing and tire size somewhat whether a 4.56 gear feels like a "granny". With 3.07 and 31"(or larger) tires one could easily use it as a normal 1st. Mine has 3.73 rear and I usually start in 2nd unless I'm loaded down or on an incline. So it is sort of a granny in my case. But I can still go 0-26 MPH in 1st if I want to. -BA

Eric Johnson, that's cool that you have the original build sheet. Mine is long gone and there was never even a SPID in the glove box.

[Eric Johnson]

Originally Posted by WorkinLonghorn

I would call Novak in the above link and ask to talk to the NP435 specialist.

As for "granny" first gear; It depends on the differential gearing and tire size somewhat whether a 4.56 gear feels like a "granny". With 3.07 and 31"(or larger) tires one could easily use it as a normal 1st. Mine has 3.73 rear and I usually start in 2nd unless I'm loaded down or on an incline. So it is sort of a granny in my case. But I can still go 0-26 MPH in 1st if I want to. -BA

Eric Johnson, that's cool that you have the original build sheet. Mine is long gone and there was never even a SPID in the glove box.

Yes. Fortunate to have it!

Don't know what my first ratio is, but first is way to low to use in normal driving. Very low and whines. Reverse is super low as well. Very similar...