TedH

I got an inquiry on my Dana for sale. Fella asked if it was Dana 36 or 44 and he says he thinks '36 since it carries 3.08 gears. Does that have anything to do with it (number of teeth)? If that is the case, my assumption about it being a Dana 44 is all wrong.

My understanding was that Dana 44 all installed in 1980-82 corvettes. True or false?

Monty

True, 80-82's all used a modified Dana 44. I rebuilt mine a few years ago and used a Dana 44 rebuilt kit from DTS.

Twin_Turbo

C4 uses superDana44

C4:



80-82:



Marck

TedH

I recalled the unit also being referred to as the Dana 44 by the shop that rebuilt it (blueprinted and new 3.54:1 Spicer gears installed).

That whole Dana 36 angle got me confused.

Weren't Dana 36's installed in some C4's?

Twin_Turbo

all automatics and the early manuals

TedH

That may be where the other guy got confused as he also said Dana 36 in the automatic cars and '44 in manuals. He just applied that to the C3's in error (I assume).

81vette

What was in the earlier C3's (68-79), and was it a tougher unit than the Dana 44?

Mark

LAvetteman

How hard is it to rebuild a dana rear end? Any tips?

MotorHead

Dana 44 is a tough rear end and match that up with a Super T 10 tranny and you've got a pretty darn strong drivetrain combination :D

TedH

The earlier years, 63-79 had a cast iron differential housing that attached to the frame using a steel brace. Different arrangement entirely. Article from the May '81 Hot Rod says 'not an easy swap' and you probably have a stronger differential than the Dana 44. Some of the internal steel parts dimensions are greater and the cast iron diff's are not as prone to twisting under high-torque applications (over 450 ft lbs).

TedH

I had a professional perform the rebuild due to the critical measurements required to get everything set up right.

Monty

I rebuilt mine and it wasn't too hard. the hardest part was replacing the clutch pack. Rather than springs, the 80-82 uses conical shaped washers to provide preload to the clutch pack, and it was a real PITA trying to get them back in place with all the special J-XXXX tools the shops manuals mention. As for all the shims, I just made not of the location, size and quantity of them as I dissassembled it, and replaced them with new, but identical shims in the same locations as the originals. I applied marking compound and it looed great, and I've probably put 30K miles on it since. As long as you are not changing the ring and pinion, it should go back the same way it came apart.

VegasJen

still not sure about this guys. i can't find any backup to support me but i could swear that the '80-'81 automatics used the dana 36 and sticks used 44s. my brother-in-law also has an '81 and we did some work on it a while back. although we did not pull his out, we did do u-joints. i DO know that the stub axles/half shafts on his automatic car uses joints 1/2" smaller than my 4-speed car. his half shafts are also smaller. it was my understanding that the '80-'82 aluminum diff was a precursor to the c-4. i'm lost. i imagine i'm wrong in this case although i could swear these units are different.
ted, i might still be interested if the stub axles accept a 3" u-joint. i could use a lower gear than my 2.72.

Twin_Turbo

Yes, 80-81 auto trannies use the smaller U-joint, the sticks & 82 have the larger ones. The differential itself is the same.

Marck

TedH

Correct. Different sizes on some parts but differential was Dana 44 for both. Per May '81 Hot Rod: "... There are now separate right and left-hand parts, as well as different shafts for manual and automatic-transmission-equipped vehicles. The new shafts are slightly larger in diameter than the old ones, and have 30 splines compared to the old unit's (Eaton) 17. The new manual shaft is slightly beefier than the automatic part, having a larger U-joint finger diameter (1.187 compated to 1.062). In fact, the manual unit accepts the same heavy-duty "1350-series" U-joint as the '75-'79 Vette. "

As a side-note, I still have ALOT of old Hot Rod magazines from my high-school days (77-82). Also a goodly number of them from early-to-late 80's overall. Subscriptions trailed off in 90's as I was less involved in rodding. Always fun to dust off the old mags and chuckle at the 'V-8's are dead... ' articles from 1980. Heck, even Smokey Yunick was announcing the demise of the small block back then. Crystal ***** must have been cloudy.


[Modified by TedH, 12:52 PM 9/24/2002]

TedH

If you have a manual trans, you will have to swap your side yokes, half-shafts and associated u-joints for use with my 3.08 diff from my automatic car.

Twin_Turbo

left & right hand




[Modified by Twinnie, 12:12 PM 9/24/2002]

82CorvetteCE

I purchased a rebuilt 82 Corvette Dana 44 ICA w/out the side yoke axles.
The side yoke bearings are INA #F66263 with an OD 2.25" / ID 1.4".
Purchased GM NOS side yoke axles for the 82 Corvette which is the same as the 80-81 4-spd axles and the axles bearing surface where the side bearings rides on is 1.5" OD.

When the side axles are inserted into the unit with the INA bearings, it engages the spider gear splines ok however the axle stops at the face of the roller bearing and will not fully insert as the bearing ID is 1.4" and the axle OD is 1.5"

The Dana Spicer catalog shows Spicer #566002 OD 1 7/8" , ID 1.5" for the side yoke bearing however the carrier case side bearing opening is 2.25" OD. Yukon Gear & Axle bearing #YB-AX005 has the same specs as the Spicer bearing as Yukon uses Spicer and Timken #b-2412 according to their Sales Dept..
Where does this Spicer bearing install with its 1.875" OD ?
The driver side side yoke bearing bore has the INA bearing installed in the 2.25" bore and it looks like its all the way back in the bore next to the differential side bearings and there doesn't look like there's a smaller bore behind the 2.25" bore.
The passenger side carrier case bore has a smaller bore stepped-up past the outside 2.25" bore.

Haven't removed the INA bearings...yet...as it's a bear to remove until I get more info on how to replace the bearing with the Spicer bearing.

I'm considering machining the axles down from 1.5" to 1.4" as doesn't seem to have a bearing available with an OD 2.25 & ID 1.5" if there's no way to install the Spicer bearing. Machining would cost approx. $150.

I wonder if the 80-81 automatic side yoke axles are 1.4" OD and the 4-spd axles are 1.5" or are both axles 1.4"OD ?

Also wonder why both the Dana Catalog and Yukon Gear & Axle bearings show the bearing specs OD 1.875" , ID 1.5" if the carrier case is 2.25" ?
I've sent inquiries to both Dana Spicer & Yukon Gear & Axle.

Is the carrier aluminum case different for the 80-81 Auto and 80-81 4-spd/82 Auto to account for the different side yoke bearing bore ?

82CorvetteCE

Did you use the Kent Moore spreader to pull the differential or pry it out with the spreader ?
If done w/out the spreader, how hard is it to get the differential back into the case with the side shims ?

Thanks.

tracdogg2

Time to post pics because what you are saying does not make sense.
The only difference between 80-82 diffs is the size of the u-joints, the rest of the sub axle is the same. Same housing, spiders, clutches, splines.... everything is the same.
Dana 44's do not use shims behind the side bearing races. The shims are installed behind the bearings. The spreader is not needed.
Mike