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Old 05-16-2015, 10:21 AM   #1
Gregski
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What can be said about the 4-speed New Process NV833 overdrive manual transmission?

I did search the forum but could not find anything relevant.

So word on the street is the 1980-85 two wheel drive trucks may have had the 4-speed New Process NV833 overdrive manual transmission. (this being a popular Mopar transmission)

1st = 3.09
2nd = 1.67
3rd = 1.00
4th = 0.73

I currently have the 4-speed Muncie SM465 manual transmission, which only has 3 gears, the Low being useless for me and my driving needs. So it's just a practical 3 speed with a 1.00:1 tallest gear.

First Gear - 6.55:1
Second Gear - 3.58:1
Third Gear - 1.70:1
Fourth Gear - 1.00:1
Reverse - 6.09:1

Have any of you done the swap, how difficult is it? Can I use my old bellhousing?

here's some pics off the InterWebs
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Last edited by Gregski; 12-07-2018 at 10:20 PM.
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Old 05-16-2015, 11:32 AM   #2
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Re: What can be said about the 4-speed New Process NV833 overdrive manual transmissio

I can't say enough good things about it.

Available through '87 (at least, also available in 4wd Blazer) as RPO MY6 (New Process A833), it is smooth shifting (uses auto trans fluid) and durable. Factory Hurst shifter. Works perfectly with a 3.73 rear axle and P235 tires.

I have 213,000 miles on mine.

http://67-72chevytrucks.com/vboard/s...highlight=a833

http://www.hotrod.com/how-to/transmi...-case-buildup/

http://www.hotrod.com/how-to/transmi...-speed-tranny/

http://www.hotrod.com/how-to/transmi...-modification/

http://67-72chevytrucks.com/vboard/s...highlight=a833

http://67-72chevytrucks.com/vboard/s...highlight=a833

http://67-72chevytrucks.com/vboard/s...highlight=a833

etc



K
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Old 05-16-2015, 11:50 AM   #3
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Re: What can be said about the 4-speed New Process NV833 overdrive manual transmissio

Search on A-833 here (40+ hits) and in Engine/Drivetrain (22 hits).
Good light duty trans, not a Hemi A833, great for low torque and moderate RPM. Most are Mopar bolt pattern and will not fit into GM belhoousings. The front bearing retainer is too big for most GM bells. Shfter is unique and hard to come by, Mopar truck shifters will work if modded. 2wd and 4wd, 4wd output shafts are a different length. That's a starter.
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Old 05-16-2015, 11:52 AM   #4
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Re: What can be said about the 4-speed New Process NV833 overdrive manual transmissio

Thank you so much Keith for the links, you looked at my watch and told me what time it is, LOL, I am embarrassed I did not find them myself, I recon it is on the account I was a searchin' for "NV833" instead of "A833" but not even just looking for "833" found those

I got sum a readin' ta do
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Old 05-16-2015, 11:54 AM   #5
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Re: What can be said about the 4-speed New Process NV833 overdrive manual transmissio

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Originally Posted by Gregski View Post
Thank you so much Keith for the links, you looked at my watch and told me what time it is, LOL, I am embarrassed I did not find them myself, I recon it is on the account I was a searchin' for "NV833" instead of "A833" but not even just looking for "833" found those

I got sum a readin' ta do
Yep - I think so too.

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Old 05-16-2015, 12:53 PM   #6
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Re: What can be said about the 4-speed New Process NV833 overdrive manual transmissio

Interesting option to the conventional car 4 speed as in the Muncie M21 or M22. But I wonder if it would stand up being behind a 454. I was/am thinking about putting an M22 behind my 454. I prefer a manual to auto but a TH400 is hard to beat strength wise.
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Old 05-16-2015, 09:23 PM   #7
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Re: What can be said about the 4-speed New Process NV833 overdrive manual transmissio

I have a 2wd one sitting in my shop. not sure what I will do with it. its a complete trans and bellhousing, only thing missing is the shifter. the bellhousing I have with it only fits it, but I have another bellhousing I'm using in a lancruiser for the wife, thats a hydro bell, and it has the boltholes for that trans or a regular gm one. if it was 4x4 I'd prob use it in the lancruiser rather than the sm465.
that bellhousing you posted has the dual pattern as well. it will take either trans.
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Old 05-17-2015, 06:47 AM   #8
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Re: What can be said about the 4-speed New Process NV833 overdrive manual transmissio

The overdrive version of the A833 was never offered behind a big block. It's not a strong trans for torque motors. Keith tows with his because he knows how to shift one and his 4.3 is a good match.
I would like to try one behind my 250. I've got a 2wd hydro clutch and a 4wd mech clutch, and keep thinking my 77 with its 250 and 3OTT could use some love. Then again, with my knees, I might just swap in an auto trans.
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Old 05-17-2015, 11:01 AM   #9
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Re: What can be said about the 4-speed New Process NV833 overdrive manual transmissio

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The overdrive version of the A833 was never offered behind a big block. It's not a strong trans for torque motors.
I kinda figured that. The way I drive, I'd most likely kill that trans in a few days.
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Old 05-17-2015, 12:04 PM   #10
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Re: What can be said about the 4-speed New Process NV833 overdrive manual transmissio

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Originally Posted by Titomars View Post
I kinda figured that. The way I drive, I'd most likely kill that trans in a few days.
I'm confused were there two flavors of this trans cause talking to my Mopar buddy who is building a '71 Challenger race car right now so he knows his stuff he says those are great transmissions strong as hell and used by Mopars with the big blocks, FYI he is not putting one in, to this car I was just making a point the guy can wrench
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Old 05-17-2015, 02:05 PM   #11
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Re: What can be said about the 4-speed New Process NV833 overdrive manual transmissio

If you have a later hydro bell on your SM465, it should have the dual bolt pattern (GM and Dodge) and can take any version of the GM NP833. The trans almost has the larger front bearing to utilize the same bellhousing, presumably a cost savings move by GM.
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Old 05-17-2015, 02:28 PM   #12
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Re: What can be said about the 4-speed New Process NV833 overdrive manual transmissio

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Originally Posted by Gregski View Post
I'm confused were there two flavors of this trans cause talking to my Mopar buddy who is building a '71 Challenger race car right now so he knows his stuff he says those are great transmissions strong as hell and used by Mopars with the big blocks, FYI he is not putting one in, to this car I was just making a point the guy can wrench
The 60's/70's Mopar version is equivalent to the Ford top loader and the Muncie M21 of that era. It was a cast iron heavy duty car 4 speed with 4th at 1:1. Typical of all Mopars they had a ridiculously long tail housing. But they were a good 4 speed in the day.
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Old 05-18-2015, 06:26 AM   #13
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Re: What can be said about the 4-speed New Process NV833 overdrive manual transmissio

Quote:
Originally Posted by Gregski View Post
I'm confused were there two flavors of this trans cause talking to my Mopar buddy who is building a '71 Challenger race car right now so he knows his stuff he says those are great transmissions strong as hell and used by Mopars with the big blocks, FYI he is not putting one in, to this car I was just making a point the guy can wrench
The original A-833's were a heavy duty 4 speed with conventional gearing. They even made a super strong version for the Hemi cars.

The version we are talking about, they flipped the gear clusters to give an overdrive, resulting in a super low 1st gear. Most of them are aluminuim, not cast iron cases (it appears the 4wd version may be cast iron), and will flex under heavy load, causing the shfts to go out of alignment. The revised shafts are much weaker than the original version. One of the shift levers is flpped to make this work.
GM offered them behind 4.3's and 305's, plus the 6.2 diesel which was desinged to match the 305 in power. They are not a high torque drag race capable trans like the original A-833! Big block and slicks = bang!
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Old 08-08-2016, 04:08 PM   #14
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Re: What can be said about the 4-speed New Process NV833 overdrive manual transmissio

Quote:
Originally Posted by D13 View Post
The overdrive version of the A833 was never offered behind a big block. It's not a strong trans for torque motors. Keith tows with his because he knows how to shift one and his 4.3 is a good match.
I would like to try one behind my 250. I've got a 2wd hydro clutch and a 4wd mech clutch, and keep thinking my 77 with its 250 and 3OTT could use some love. Then again, with my knees, I might just swap in an auto trans.
Mine came stock behind the 6.2
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Old 05-17-2015, 09:18 AM   #15
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Re: What can be said about the 4-speed New Process NV833 overdrive manual transmissio

My father bought an 87 R10 short fleet brand new. 305 with that A883 4 speed. He loved it. I remember him towing his 66 427 Chevelle to the track with it. I was a little tike. I think he sold it with 125,000 on it, no clutch rebuild either.

Hard to find, from what I have seen here on the net.
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Old 05-17-2015, 10:18 AM   #16
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Re: What can be said about the 4-speed New Process NV833 overdrive manual transmissio

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My father bought an 87 R10 short fleet brand new. 305 with that A883 4 speed. He loved it. I remember him towing his 66 427 Chevelle to the track with it. I was a little tike. I think he sold it with 125,000 on it, no clutch rebuild either.

Hard to find, from what I have seen here on the net.

...





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Old 05-17-2015, 03:51 PM   #17
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Re: What can be said about the 4-speed New Process NV833 overdrive manual transmissio

At the rate I've blown up muncies [first the oem sm465, then the M20 twice] I doubt the nv833 can be that much weaker lol. Its not all in how you drive them either. I was exceedingly easy on the 2nd M20 rebuild but torque to the wheels is torque to the wheels and sometimes they just can't handle it.
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Old 12-07-2015, 12:19 AM   #18
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Re: What can be said about the 4-speed New Process NV833 overdrive manual transmissio

Well today I got me one, it wasn't cheap and it wasn't close by, so I am broke but I am happy.

It cost me $950 dollars and a 350 mile drive each way. The guy would not budge on the price, in the end I asked if he would go for $900 and he would not drop $50 bucks, oh well.

This is off of a 1982 Chevy 1/2 ton 6.2 diesel 2WD.

I bought it from a guy who bought it from another guy.

To sweeten the deal I had him throw in the bell housing, clutch & brake pedal assembly (just in case) and a transmission cross member off of a 1984 4x4 automatic. (more on that later).

So there is a lot to talk about here, and this swap may not happen until Spring but I just wanted to share, and start asking some questions.

Pic 1 - how it was listed on Craigslist

Pic 2 - we found the missing bellhousing under an old tarp in front of the passenger seat

Pic 3 - the loot in the trunk of my car
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Old 12-07-2015, 12:24 AM   #19
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Re: What can be said about the 4-speed New Process NV833 overdrive manual transmissio

So the first question / comment I have is regarding the mechanical clutch assembly bellhousing I got for this bad boy.

I was under the impression that these transmission used a hydraulic clutch assembly, and then this guy shows me this bell housing which indeed matches the bolt pattern of this transmission yet it has the mechanical linkage fork in it and no provisions for the hydraulic clutch slave cylinder.

Again remember this guy does not have the original truck this came out of, so we were unable to take a look see on how this was originally set up, but he swears the bellhousing is original to this transmission and he bought them as a set.

So could some of you more experienced folks comment on weather these transmission came with either a mechanical Z-bar like clutch linkage and or a hydraulic clutch or this mechanical setup is just not going to work for me?
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Old 12-07-2015, 07:46 AM   #20
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Re: What can be said about the 4-speed New Process NV833 overdrive manual transmissio

Both hydro and mech clutch versions are available, I actually have one of each.
The early ones, particularly 4wd, seem to be mechanical.
For most of these the pattern on the bellhousing is unique to this trans, although there are some that apparently have the Chevy pattern.
To check you have the correct bell, line up hte pattern. Then check if the front bearing retainer just slides into the bell. This is larger than the Muncie / Sagniaw GM front retainers and the bell should just fit it. This is critical to the alignment of the trans.
I see you got the shifter, that's the other critical part.
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Old 12-07-2015, 09:03 AM   #21
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Re: What can be said about the 4-speed New Process NV833 overdrive manual transmissio

85+ trucks are hydro clutch, regardless of which transmission it came with. You could get an 85+ SM465 bell. Or buy the advanced adapters hydro conversion bracket.
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Old 12-07-2015, 11:12 AM   #22
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Re: What can be said about the 4-speed New Process NV833 overdrive manual transmissio

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85+ trucks are hydro clutch, regardless of which transmission it came with. You could get an 85+ SM465 bell. Or buy the advanced adapters hydro conversion bracket.
Thank you Eric, that makes sense these parts being off of an '82. I don't know much about the 80 and up trucks, mine is a '74 so I mostly dwell in the 1973-1979 arena, and still believe they should have split the 73-87 trucks into two Generations, Gen 3 should be 1973-1979 and Gen 4 should have been 1980-1987 but lets not start WWWIII over this, ha ha

once again I thank you for your feedback
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Old 12-07-2015, 02:12 PM   #23
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Re: What can be said about the 4-speed New Process NV833 overdrive manual transmissio

The MM7 is the 4x4 version.
The MY6 is the 2WD unit you just bought
.
It's pretty much the same aluminum case NP A833 Dodge used in the Ram trucks with a GM input shaft and output spline count.
Make sure the countershaft plug seals properly and the countershaft isn't rotating in the case.. And don't use gear oil in it.

The shifter isn't that odd.
It's an OEM side mount Hurst Competition Plus shifter. You can get them freshened up by Hurst if the shifter itself is terribly loose. If it's not loose clean it up and lube it.
The Hurst plastic bushings and spring clips for the relay rods are available from Summit Jegs etc.
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Last edited by hatzie; 12-07-2015 at 02:19 PM.
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Old 12-07-2015, 05:43 PM   #24
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Re: What can be said about the 4-speed New Process NV833 overdrive manual transmissio

Quote:
Originally Posted by hatzie View Post
...

The shifter isn't that odd.
It's an OEM side mount Hurst Competition Plus shifter. You can get them freshened up by Hurst if the shifter itself is terribly loose. If it's not loose clean it up and lube it...
Thanks bud, that helps I did not know what the model was I just heard of them referred to as Hurst shifters so that helps.
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Old 12-08-2015, 12:26 PM   #25
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Re: What can be said about the 4-speed New Process NV833 overdrive manual transmissio

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Thanks bud, that helps I did not know what the model was I just heard of them referred to as Hurst shifters so that helps.
It's a Competition Plus made by Hurst for use by GM on the MY6 & MM7 A833. A lot of the OEM side mount shifters from the 50's through the 80's were Hurst units.
Fairly easy to re-work as long as it's not shagged completely out. The shim plates and springs are available.
This guy is hawking his hardened shift rod bushings. They transfer the wear to the soft harder to replace parts. I'd just use the nylon Hurst Pit Pack bushings.

6 bolts is probably gilding the lily. The SM465 does fine with just 4. It's heavier than a dead horse.
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RTFM... GM Parts Books, GM Schematics, GM service manuals, and GM training materials...Please include at least the year and model in your threads. It'll be easier to answer your questions.
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Last edited by hatzie; 12-08-2015 at 01:45 PM.
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