What can be said about the 4-speed New Process NV833 overdrive manual transmission?

[Dazzoman]

Originally Posted by hatzie

I've run the Dodge Aluminum A833 OD behind a 340 in a 1/2 ton Dodge Pickup with a mild almost RV grind cam. The only serious difference is the Dodge dimensioned input shaft and maybe the output shaft spline count.

I have a 1:1 4th gear Cast Iron A833 behind a 383 in a C-Body 69 Dodge Polara.

I really don't see what the wild difference is between the CI case transmission and the aluminum case version is. The Al case is actually slightly thicker than the CI case.

I believe the 4x4 version of the GM A833 OD trans is an MM7. 2WD is MY6.

The Cast Iron Case version should work fine with a 350. I'd be sure to check all the bearings etc before you put it in. They are close to 40 years old and lord only knows what the previous owners did to it.

Perfect !
Your'e right . And this iron MY6 was made in 1982 !
I'm running it behind the stock 292 and it is perfect and tight , of course we replaced all the seals / gaskets .
I got it from an trans shop that happened to have it ready to go and they went thru the basics before they sold it to me .
Thats good news about the AL case because I have one ( but with the van shifter darn it ) .
I was thinking of putting that in an 1966 Ford van Im getting ha ha !
Ford didn't offer room for the shifting or much less an OD trans for the stock 6 cyl it had .I might put the 292 in it lol ! Or not if it doesnt fit :0P

[D13]

4wd - yes, there are GM factory 4wd versions, I have one in my shed with the correct adapter for an NP208 ( Actually, I think I have the NP208 too. But it's 0F out and I'm lazy). These have a different length and spline output shaft and are cast iron cases.

Torque capability - the issue is that the gear flip lowers torque capability compared to the direct drive. You get a really low first, allowing huge torque loads on the output side, and a really tall overdrive, requiring a lot of torque on the input side. Note these trans' were never offered behind anything bigger than a 305 in the GM line, and most of the Dodge applications are slant 6 or 318. I suspect the failure mode comes about when someone decides to tow a heavy load, which would explain why they were not offered in 3/4 tons.

The big key here is the operator. If you know how to drive it, it works great, witness Keith's many years of towing with his.

Iron vs aluminum - aluminum housing has wear issues in the countershaft bore but does not seem to directly be a strength issue. Although, all the GM 4wd versions use the iron case. I have never seen a GM iron case 2wd, although there is no reason it might not exist, and it certainly would be easy enough to build one by switching out cases.

I've not personally had any experience with the GM van applications.

[Dazzoman]

Hatzie said the aluminum MY6 is thicker than the cast but I was told by Passon transmission shop (who specialize in these and have an half dozen fresh built ones on the wall ready to ship), that the Aluminum ones have an propensity to wear in the countershaft bore (like you said ) .
Well I'm gonna not do any broadys or burnouts and keep it light on the foot- but I will probly go like hell on the freeway when I get an freshly built 350 in this iron MY6 / 1966 GMC 3/4 ton . I found an rebuilt 350 this morning from the guy who I bought the MY6 from. He will trade me the 350 for the MY6 including bell housing and shifter . Seems like an no brainer . He has been straight on with me about everything so it all looks good .
I'll note all of you when that conversion is done . I have to get all the exhust , power steering , mounts etc stuff all redone so it could take another month in this weather .
Its gonna be sweet as *#&% when its done !

[LT7A]

Originally Posted by D13

4wd - yes, there are GM factory 4wd versions, I have one in my shed with the correct adapter for an NP208 ( Actually, I think I have the NP208 too. But it's 0F out and I'm lazy). These have a different length and spline output shaft

That's more good info. Thanks D one three. Do you know if there is a seal on the output shaft or does the fluid circulate freely between the transmission and the transfer case? I've seen a tail shaft housing for a 4WD version, and it looks like it has two tabs with holes to bolt to a cross member. But if there's no seal around the shaft, then there would need to be an adapter or plate or something to seal in the fluid. It seems like I ought to be able to get the correct splined female connection for the drive shaft. The drive shaft may need to be adjusted in length though.

[65Robb]

So for everyone that has done this swap what styles of hurst shifter boots is everyone using? Thanks

[hatzie]

Originally Posted by Dazzoman

Hatzie said the aluminum MY6 is thicker than the cast but I was told by Passon transmission shop (who specialize in these and have an half dozen fresh built ones on the wall ready to ship), that the Aluminum ones have an propensity to wear in the countershaft bore (like you said ) .

One of the common repair/upgrades made to the AL case is a countershaft bushing. Don't think about it just do it.
The countershaft is fairly loose from the factory. The floating countershaft wallows out the case which spreads the distance between the mainshaft gears and the countershaft gears. When the clearance gets to be too large you get a BANG!!! and the party is over.

[D13]

Originally Posted by LT7A

I've seen a tail shaft housing for a 4WD version, and it looks like it has two tabs with holes to bolt to a cross member. But if there's no seal around the shaft, then there would need to be an adapter or plate or something to seal in the fluid. It seems like I ought to be able to get the correct splined female connection for the drive shaft. The drive shaft may need to be adjusted in length though.

The output shaft, internal to the trans, is the correct spline and length to engage the tcase gears. The adapter / spacer replaces the trans output housing, bolts directly to the tcase, and has the standard 2 bolt mounting common to all the later square 4x4's, and should use the common later cross member. I 'think' the tcase is sealed from the trans, but on the tcase not the adapter.
Speedo drive moves from trans to t-case. IIRC the 4wd shaft does not have speedo drive provisions.

[Dazzoman]

Originally Posted by hatzie

One of the common repair/upgrades made to the AL case is a countershaft bushing. Don't think about it just do it.
The countershaft is fairly loose from the factory. The floating countershaft wallows out the case which spreads the distance between the mainshaft gears and the countershaft gears. When the clearance gets to be too large you get a BANG!!! and the party is over.

Sounds very true and I will do that if I ever get into another Al MY6.
I just traded mine yesterday for an freshly rebuilt 350 block w/ heads .

[Gregski]

Originally Posted by Dazzoman

OK cool .
I was told to use regular engine oil like an 30 weight , try that maybe...

So finally got around to draining the expensive ACDelco Manual Transmission and Transfer Case Fluid 10-4033 and replaced it with some SAE 30 motor oil. I did this to see if the transmission noises in neutral and especially 2nd gear would go away. In neutral it sounds like the clutch is engaged or rubbing or something, it grinds a little bit as the input shaft is spinning. In second gear it sounds like Chubbaca is chocking on a wet dog especially if I am just idling in 2nd gear like in a parking lot or something.

I tilt the truck like so to get the last 1/2 quart out, you would be surprised how much more fluid comes out when you do this.

RESULTS: no difference, same sounds as before, I think it is time for a new input shaft bearing

I am not saying you should do this ie run 30 weight motor oil in these transmissions but I have heard old timers recommending this trick to quiet them down, so I just wanted to try it and give you guys a report, other than that, love this gear box

[Dazzoman]

Ok good - you just taught us that regardless it is better to fix it than to risk it .
much oblidged .
I love my set up and it works perfect .
Dazzoman

[LT7A]

Originally Posted by Gregski

I am not saying you should do this ie run 30 weight motor oil in these transmissions but I have heard old timers recommending this trick to quiet them down, so I just wanted to try it and give you guys a report, other than that, love this gear box

Any benefit to running it over-full? IIRC, there is an HD transmission that the big diesel guys run with Cummins conversions and such. Maybe it is the NV4500? Anyway, I think they run it a full quart "over-full". Unfortunately, I don't know enough to actually recommend this. Just wondering aloud and bummed that your cool setup is giving you fits.

[D13]

There is no advantage to overfilling it. If anything it makes it want to leak more.
Use the correct lube, some oils do not play well with the materials in the synchronizers. IIRC ATF was spec'd for some years, then probably Synchromesh. Note these are lighter to help cold shifting, but still have high temp capabilities.

[65Robb]

I used napa atf dextron 3 with lucas additive conditioner an mine doesn't make a lot of noise it just sounds like a syncronized transmission.

[Keith Seymore]

Originally Posted by hatzie

The MM7 is the 4x4 version.
The MY6 is the 2WD unit you just bought

Just clarifying this point:

MM7 is the "merchandised" option code.

MY6 is the "non-merchandised" option code.

The merchandised option code is the one the customer selects (ie, "I want a manual overdrive trans", or "I want an automatic trans"). The non-merchandised option code is the specific trans, in terms of capacity or gear ratios, that the engineering release charts choose on the customer's behalf, taking into consideration powertrain, GVW rating, etc.

It doesn't really matter when there is only one trans part number offered, but when there are multiple choices then it becomes significant.

Example: let's say you want a "three on the tree":

You tell your dealer and he chooses the "merchandised" option "MM3" = manual trans 3 speed.

From that then the engineering charts choose non-merchandised RPO M62 or M64, depending on the first gear ratio required for your specific powertrain and GVW.

Another example: you say "I want the manual trans with a creeper gear".

Dealer selects the merchandised option "MM4", but there is only one part number available, the non-merchandised option M20, so the two option codes can be used interchangeably.

K

[walkerb]

Just wanted to update my progress

Had to pull my Saginaw trans this weekend. So that forced me into the swap!

Saginaw and Nv833 are the same length, hub bearing size are the same so my sag bell housing fit the 833.

Throw out bearing diameter is also the same..... 1 3/8"

Only issue was the bottom right side trans to bell housing bolt was too long so ill have to source a shorter bolt

And in one of the pics you'll see that the Sag is a truck 5 bolt Sag and the Nv833 is a 4 bolt

I havent reinstalled yet, waiting on parts but should be good.

Cant wait to have a 3200lbs truck with a 250 and 373 gears

[Dazzoman]

For what its worth on my original 1966 bell housing I made two straps that proved to work and I have a posted a picture (somewhere here) of the "kit" I made for it with the bolts & washers .
Looks like you only need one of these straps and consists of 3/4 or 1/2 thick rectangle steel plate with two holes on the ends .
If you cant find that pic I can find something for you .

[Dazzoman]

Here is pics of my strap kit for this conversion of the NP440 for my 66 GMC bell housing (that went originally for the 305 V6 ) .
Cheers

[dragonball98312]

Originally Posted by Dazzoman

Here is pics of my strap kit for this conversion of the NP440 for my 66 GMC bell housing (that went originally for the 305 V6 ) .
Cheers

You going to run this behind the v6?

[Dazzoman]

Originally Posted by dragonball98312

You going to run this behind the v6?

Ha ha ha , no sir !
I curently have an 292
I am building an 350 .....its an 1988 block , heads so far .

[Mac the Yankee]

Bumping this back to the top!

Been reading through this thread, as I just picked up an iron case 833 that will go behind a 348 W-motor for my '56 Panel Truck project- neat to see that Brad54's article in CCT was mentioned, as Brad is one of my best friends, and I picked up the tranny at his swap meet last Saturday (if you haven't been to the NEGA swapmeet at Atlanta Dragway, you need to come out)!

The gentleman only had the transmission, so I'm on the hunt for a bellhousing and shifter/rods, but thanks to everyone who's posted on this thread- LOTS of great information!

Quick question- did the head duty linkage rods only come on the 4X4 transmission, or on the 2WD as well?

[bluek5]

Originally Posted by Mac the Yankee

Bumping this back to the top!

Been reading through this thread, as I just picked up an iron case 833 that will go behind a 348 W-motor for my '56 Panel Truck project- neat to see that Brad54's article in CCT was mentioned, as Brad is one of my best friends, and I picked up the tranny at his swap meet last Saturday (if you haven't been to the NEGA swapmeet at Atlanta Dragway, you need to come out)!

The gentleman only had the transmission, so I'm on the hunt for a bellhousing and shifter/rods, but thanks to everyone who's posted on this thread- LOTS of great information!

Quick question- did the head duty rods only come on the 4X4 transmission, or on the 2WD as well?

I have a shifter here if interested. http://67-72chevytrucks.com/vboard/s...d.php?t=737354

[Dazzoman]

Originally Posted by Chevystep

For those of you using this tranny in your 60-66 with stock wheels, what speedo gear do you need to make the speedometer read correctly. Driven gear numbers? Summit racing?

My truck has 16 inch wheels and for some lucky reason my 1982 cast iron NP440 tranny matched perfectly - regarding the speedo cable . Of course I had to get a longer cable but it matched better than my original 4 spd granny box .
Mind you I changed the Dana/Spicer rear end ring gear to the highest it would except and go in this year ( they made mine up until 1971 in this case ) 354 or something .
It was accidental but perfect match .

[D13]

Originally Posted by Mac the Yankee

Quick question- did the head duty linkage rods only come on the 4X4 transmission, or on the 2WD as well?

I've been diggin through my pile o'parts and come to the conclusin that my 'HD' shift rods are actually DODGE CAR parts. Keys is that the rods use the big bushings vs the GM's use of Muncie/Saginaw style, and the stick is bolt on not snap in. Also the shifter arm is bent almost 90 degrees, would stick into the seat. Shifter plates are also different than the GM ones.

The mounting plate of the Dodge sits too far forward to clear a 4wd adapter. I'm currently looking for the trans side arms to see if the Dodge arm/rods will work with the GM mount plate.

Shift rod strength should not be an issue unless you plan on seriously offroading in which case you have the wrong trans anyways....

[Mac the Yankee]

D13,

Thanks for the info! From talking with Brad(54), the Dodge and Chevrolet parts are not interchangeable, and all are in agreement that HD shift rods are not necessary for my plans

[Dazzoman]

Originally Posted by D13

I've been diggin through my pile o'parts and come to the conclusin that my 'HD' shift rods are actually DODGE CAR parts. Keys is that the rods use the big bushings vs the GM's use of Muncie/Saginaw style, and the stick is bolt on not snap in. Also the shifter arm is bent almost 90 degrees, would stick into the seat. Shifter plates are also different than the GM ones.

The mounting plate of the Dodge sits too far forward to clear a 4wd adapter. I'm currently looking for the trans side arms to see if the Dodge arm/rods will work with the GM mount plate.

Shift rod strength should not be an issue unless you plan on seriously offroading in which case you have the wrong trans anyways....

What yr and make is your truck ?
My shifter now fits near the seat and I had to bend it out a tad ( torch/ big vice)so it would straighten out .
Your right it would otherwise be too close ....