Steel cap for Dana 44

[69427]

Another question. Several guys have mentioned the swap of the iron and aluminum units in their car. Can I then assume that the width (inner u-joint to inner u-joint) is the same?

 

[tracdogg2]

The finished diff with steel cap.

 

[tracdogg2]

Another question. Several guys have mentioned the swap of the iron and aluminum units in their car. Can I then assume that the width (inner u-joint to inner u-joint) is the same?

No, they're not the same. If you convert from a Dana to an iron diff you have to change the spindle flanges and the halfshafts.
Mike

 

[69427]

Another question. Several guys have mentioned the swap of the iron and aluminum units in their car. Can I then assume that the width (inner u-joint to inner u-joint) is the same?

No, they're not the same. If you convert from a Dana to an iron diff you have to change the spindle flanges and the halfshafts.
Mike

Are the halfshafts shorter?

 

[69427]

I'm trying to come up to speed on the C3 D44 (all my rebuilding experience is with the iron units). Here's what I've gathered from this thread, and my questions to learn more.

1) An earlier post stated that the D44 posi carrier is stronger than the earlier iron case units. What comprised this improvement?

2) The stub axles are larger. The diameter and spline count is what compared to the older units?

3) 8.5 inch ring gear. What is the older ring gear size?

4) What was Chevy's reasoning for two different versions of this rear end (auto and manual versions), given that Chevy then put the "manual" version in the "all auto" '81 model year cars? It's usually more expensive to produce two different versions of a product, unless one version is just incredibly cheaper than the other.

5) What are the halfshaft differences between 63-79 and 80-82 units?

6) Do we have an accurate weight difference between the iron and aluminum rears, without the covers (for apples to apples comparison)?

7) Who's the slim in Tracdogg's avatar?

Just trying to catch up here.

 

[tracdogg2]

Hi Mike,

1. The carrier is thicker and has more neat around the cross shaft. But the clutches are smaller.
2. I'll get you some comparison pics
3. If memory serves correct 8.2
4. No idea. I wouldn't use a D36 in a riding lawnmower.
5. Slightly shorter and thinner metal used in the tubes on the 80-82
6. I'm shipping this diff tomorrow so I will have an exact weight
7. My daughter
Mike

 

[69427]

Hi Mike,

1. The carrier is thicker and has more neat around the cross shaft. But the clutches are smaller.
2. I'll get you some comparison pics
3. If memory serves correct 8.2
4. No idea. I wouldn't use a D36 in a riding lawnmower.
5. Slightly shorter and thinner metal used in the tubes on the 80-82
6. I'm shipping this diff tomorrow so I will have an exact weight
7. My daughter
Mike

Any update on the weight issue?

 

[MYBAD79]

6) Do we have an accurate weight difference between the iron and aluminum rears, without the covers (for apples to apples comparison)?

7) Who's the slim in Tracdogg's avatar?

6. I'm shipping this diff tomorrow so I will have an exact weight

7. My daughter

Any update on the weight issue?

I assume you're asking about the weight of the differential ??? :drink:

 

[69427]

6) Do we have an accurate weight difference between the iron and aluminum rears, without the covers (for apples to apples comparison)?

7) Who's the slim in Tracdogg's avatar?

6. I'm shipping this diff tomorrow so I will have an exact weight

7. My daughter

Any update on the weight issue?

I assume you're asking about the weight of the differential ??? :drink:

Yeah, the differential. (I think I probably already asked one too many questions about item seven anyway. LOL)

 

[tracdogg2]

The weight is right at 55 lbs without the cover. Approx. 20 lbs lighter than an iron diff.
No problem talking about my daughter, we're quite used to it.

 

[69427]

My compliments on item #7.

Back to business: What's a quick easy way to tell the auto from the manual/'82 rear ends? Any special measurements that are easy to use when wandering the swap meets?

 

[tracdogg2]

The diffs are the same except for the stub axles. 80-81 manual and all 82 use the 1350 u-joint. The bolts that hold the straps are 5/16 thread. 80-81 auto uses the 1330 joint. The distance from cap to cap is 3.62 in on both. Cap diameter is 1.06 for 1330 and 1.18 for the 1350. Also the auto stub axles use 1/4 threads to bolt the straps on.
Mike

 

[69427]

The diffs are the same except for the stub axles. 80-81 manual and all 82 use the 1350 u-joint. The bolts that hold the straps are 5/16 thread. 80-81 auto uses the 1330 joint. The distance from cap to cap is 3.62 in on both. Cap diameter is 1.06 for 1330 and 1.18 for the 1350. Also the auto stub axles use 1/4 threads to bolt the straps on.
Mike

I appreciate it. Looks like I'll just toss a 5/16 bolt in my pocket prior to the next swap meet to check the threads on the side axles. How about the pinion yoke (size), are they common to both setups?

Thanks,
Mike

 

[tracdogg2]

Yes, all the pinion yokes take the 1310 joint.
Mike

 

[Twin_Turbo]

The difference is VERY easy to spot, just by looking at the stub axles. Not only are the bolts for the 1330s 1/4, they are also drilled in a different location (closer together) so you can't even redrill them for the large bolts (wonder why GM does that, would have been so much easier if they didn't)
With the 1330 stubs the hole is significantly closer to the center. With the 5/16 ones the hole is centered in the face where the cap meets.

Here, lonestar has a nice pic: