Finally caught a break NP440 / MY 6

[Dazzoman]

Good one Brad .
I think both of mine are Chevy application but you say Mopar had this too ? Maybe the shaft splines are different on the Mopar .
Do you have an chevy aluminum bell housing ? You could use that but it will not be as toughe as the iron , same with the iron trans like you said .
I had to make an kit (pics on my early post) to fit the L side where as the R side fit my 1966 GMC Bell housing of which my truck is .
Glad you kept the original hence the older starter bolt pattern .
Even tho mine is an iron trans Im gonna make an lighter rear crossmember for the rear trans mount or I'll find an 1965 Chvy truck automatic crossmember he he ya right .
They put it there so it must be there for a reason .

[Brad54]

Originally Posted by Dazzoman

Good one Brad .
I think both of mine are Chevy application but you say Mopar had this too ? Maybe the shaft splines are different on the Mopar .
Do you have an chevy aluminum bell housing ? You could use that but it will not be as toughe as the iron , same with the iron trans like you said .
I had to make an kit (pics on my early post) to fit the L side where as the R side fit my 1966 GMC Bell housing of which my truck is .
Glad you kept the original hence the older starter bolt pattern .
Even tho mine is an iron trans Im gonna make an lighter rear crossmember for the rear trans mount or I'll find an 1965 Chvy truck automatic crossmember he he ya right .
They put it there so it must be there for a reason .

The New Process A-833 4-speed was a Mopar trans since the early '60s. In the '70s, they reworked them to make 3rd gear 1:1, and 4th is an overdrive, running through the cluster position that used to be 3rd gear in a regular 4-speed application.
A Mopar input shaft is much longer and a different spline count, the output shaft is longer (on most--the Dusters had a short shaft) and different spline count.
From what I have been able to find, there are two different transmission main case mounting patterns: the ones in your photo, which require a special (factory) re-tooled bell housing, and another with a regular GM 4-speed mounting pattern. The ones you have use a Mopar mounting pattern.
There are also at least three bellhousings: any standard GM bellhousing, an aluminum one that's been retooled for the Mopar mount and uses mechanical clutch linkage, and an aluminum that's been retooled for the Mopar mount that uses a hydraulic clutch slave on the fork. (NOT a hydraulic throw-out bearing, as was used on later trucks). I have both of the aluminum ones, and need to see which I'll ultimately use on my '61 Suburban when I put the 348 in it.
Option eleventy is I buy a Lakewood with multi-pattern trans mount, and the side mounting holes for a '57 Chevy which will also work with the '60-'62 frame. I know that can be done because I already have one of those bellhousings for my slick-shift Hemi 4-speed racing trans, as that trans has a custom input shaft for Chevy... But I'd rather not use that one as it's slated for my gasser.

-Brad

[Dazzoman]

I see :-)
Wouldn't you want to use an iron NP440 for your 62 truck because its heavy duty ?
At the very least (otherwise ) I would pop that steel sleeve in it so you can feel safe .
On bolt patterns , even tho I have ( as you say) the Mopar tranny it does bolt (GM) on on the right side , and yes of course the nose piece has been turned and allen head screws added .But on the left side I had the bracket strap set made , so far today I drove it w no probs .I found an tiny oil leak of which I thought wouldn't happen on the rear seal but put in some motor purr and it sealed it up real nice . I wouldn't have had the time to do that too , it took me over an month to do all this much . Alot of wiring stuff I did plus floor/ seat .
BTW how come I can't post the thumbnail pic of my truck on this forum ( by my name like your has ) ?
T

[Brad54]

I've thought about putting the iron case in the 4x4, for the reason you said... but the 348 Tri Power that's going in the '61 Suburban is actually a stroker motor, and will be beat on fairly regularly.
The 4x4 will be a daily driver around town, and going into the woods to hunt and fish--no rock-crawling or anything like that. I figure the Dana 44s, the lock-out hubs, front axle hug u-joints, driveshaft u-joints, and transfer case all have to break before the aluminum case on the trans explodes in 1st/4-Low!

I don't remember how I was able to post that thumbnail... I'm a bit of a luddite when it comes to things like that! Stumble around until I find it, then forget how I got there!

-Brad

[Dazzoman]

Oh ya .
Are those aluminum trannies really that beefy ? I thought they can break ....
Im fairly new to them ...

[andyh1956]

Yall know that in the 70s ford did the same thing with the toploader 4 spd & made an OD outta it. I have adapted several ford trannys to chevy engines & looks like it would be a good swap also. In the 80s ford changed to a wimpy aluminum trans that wasn't very good. I had one of the toploader o/d in a 79 f150 & it was a great trans, the 302 in front of it not so much...

[Brad54]

Originally Posted by Dazzoman

Oh ya .
Are those aluminum trannies really that beefy ? I thought they can break ....
Im fairly new to them ...

They probably aren't any more fragile than an aluminum-case Muncie--both will break behind a lot of horsepower in a heavy car, or from simple abuse.

I put almost 100,000 miles on the one in my Suburban, behind a 290hp crate engine, and I wasn't always kind to it. Never a hint of a problem.

-Brad

[65Robb]

Hey guys great thread lots of info. so I'm about ready to swap a np440 in my 65 I have a question about the drive shaft does the drive shaft have to be modified or just swap a slip yoke on it if so what slip yoke should I use?

[Dazzoman]

Originally Posted by 65Robb

Hey guys great thread lots of info. so I'm about ready to swap a np440 in my 65 I have a question about the drive shaft does the drive shaft have to be modified or just swap a slip yoke on it if so what slip yoke should I use?

In my 66 GMC I had the front portion shortened and they had to put an Stingray type front U joint unit on there so I could fit the front portion on (because it has to slide in the tranny ) . Picture .

[par4tom]

Swap the yoke...tailshaft is typical gm type...you may have to shorten your drive shaft depending on what you have in there now...

[65Robb]

Ok I have a granny 4speed with the 2 peice drive shaft in it right now

[Brad54]

Originally Posted by 65Robb

Ok I have a granny 4speed with the 2 peice drive shaft in it right now

Not gonna work. Mine had that same trans. Had to buy a new yoke (same as TH700r4), and had a one-piece driveshaft made.
My '62 Suburban came with a 1pc driveshaft with the slip-yoke built into it... so technically, it was 2-pc, but when we're talking about these trucks, I think we all typically consider a "2pc driveshaft" to mean the later ones with the carrier bearing in the middle.

-Brad

[65Robb]

Yes think they all where a 2 peice i believe lol so I will have to get a slip yoke for a th350 700r4 to make it work or just go with a 1 peice out of a later model.

[65Robb]

Ok how much did you have it shortened?

[Dazzoman]

Originally Posted by 65Robb

Ok how much did you have it shortened?

Not sure exactly but when new tran is bolted in you can measure it and take the whole 2 piece drive shaft to (in my case ) San Jose Drive Line and they will spin balance the whole thing , add new U joints etc for about $400 .

[LEEVON]

Just wanted to add to the knowledge base...I sold my very nice MY6/NP833 aluminum case unit for $550 recently. It was complete with a very nice shifter and the offset pattern bellhousing. It's going in an old hot rod. That might give you all an idea on the market value.

[65Robb]

Ok ill measure it out when I get it mounted up. Thanks for the help guys

[dracko]

There is some excellent info online on how to measure driveshaft length. For the most part the shop i used just wanted a measurement from centre to centre of the U joint pivots. Keep in mind the slip yoke should be out 1" from the seal when measuring. That gives some play to move in/out as the suspension is compressed.

[65Robb]

Ok awesome haha

[Dazzoman]

Originally Posted by 65Robb

Ok awesome haha

Right on Drako thats right .
One thing I regret is that I could have reused my old zerked U joints and here it is :
U joints that were made pre 1990s were made better and lasted longer and/but the drive line specialists might say "If they have zerk fittings thats weaker , 'BAD' plus these new non zerked joints are made to go over 100k miles without having to grease them " .
Well they are half right about the strength with the zerks but what they won't tell you ( so they can sell more ) is that you can use your old ones and they are just as strong .
You WILL have to use an new front smaller joint AND it HAS zerks !
But don't worry , it will not break .

[65Robb]

Ok sweet great info guys I'm thinking once I get the slip.yoke in ill replace all u joints and carrier bearing just so its done and won't have to worry about them for a long time.

[Dazzoman]

Originally Posted by 65Robb

Ok sweet great info guys I'm thinking once I get the slip.yoke in ill replace all u joints and carrier bearing just so its done and won't have to worry about them for a long time.

I meant if you have USA made pre 90s u joints with zerks YOU SHOULD RE USE THEM .
Otherwise if you just get the new ones (without zerks ) you are at a dis advantage because they last about 100k whereas the old style are better .
They were still into making things last when they made em .
Ya you have to grease em once and a while but they will outlast the new .

[trailcarnage]

I am so hoping that somebody in this thread can help me out...

I recently picked up one a MY6 that I am going to mount behind my LT1 in my C10. I know that the LT1 uses a 153t flywheel and a 10.4" clutch with a T56. It looks like the '84 C10 that this trans came from uses a 11" or 12" clutch. I am trying to determine what flywheel and clutch to order to this combo.

Any advice would be greatly appreciated!

[par4tom]

I have a 168 tooth ring gear on mine...
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[Captainfab]

What is the input shaft spline count on the MY6 versus the T56?