Dana 44 differential ID

Hey guys. I acquired this differential and batwing with a parts lot of first gen camaro parts. Both are new, never used. I need to identify them, year range they fit, ratio, and ballpark value. I spent about an hour searching the net, and found many similar ID stickers, but none with these numbers. I plan to list them for sale, and want to make sure all the info and details are correct, as well as a fair price.

close up of tag

What is the ratio of the diff?

That was part of the info I was looking for. I can count the teeth on the ring and pinion to figure out the ratio, but I was hoping to decode the tag for full info.

Looks like a Gen 1 (1992-1995) unit based solely on the pics.

Tag won't tell you everything you need to know, as the gear marking compound tells me someone has been in there, and recently at that as those gears haven't been run yet. It's hard to tell from just one photo, but I'd want to take a good hard look at that pattern before just slapping it in...looks like the pinion is set too shallow by my untrained eye. Backlash and total bearing preload should also be measured before installing just to make sure everything is right.

There should be a part number on the ring gear - rotate it around until you see it. That'll help, but there should also be two numbers stamped on it as well...that will for sure tell you the ratio.

• 43/14 = 43 teeth ring gear, 14 teeth pinion gear; 43 divided by 14 is 3.0714 (a.k.a. 3.07 gears)
• 39/11 = 39 teeth ring gear, 11 teeth pinion gear; 39 divided by 11 is 3.5454 (a.k.a. 3.55 gears)
• 41/11 = 41 teeth ring gear, 11 teeth pinion gear; 41 divided by 11 is 3.7272 (a.k.a. 3.73 gears)
• 43/11 = 43 teeth ring gear, 11 teeth pinion gear; 43 divided by 11 is 3.9090 (a.k.a. 3.91 gears)

If the numbers you see are different than what's listed above, just divide the larger number by the smaller number. 3.55s and 3.73s are popular aftermarket ratios for most Vipers. The stock ratio for all Vipers from 1992-2010 (Gen 1-4) is 3.07; 2013-2017 (Gen 5) Vipers came with 3.55s from the factory.

Thanks for your help, I should have thought about rotating the ring gear around. It's a dana part number on the ring gear. Stamped 39 11, so 3.55. Both the center section and rear cover were still in the box. According to the guy I bought the parts lot from, the parts were bought new and complete as shown. He thought the viper was 2002, but wasn't 100% sure. Here's a few pics of the numbers on the ring gear.

If it is 3.55 I would be interested in it if it fits.

Well, you definitely know it isn't 100% OEM. That's not the end of the world, but it does raise some questions.

What exactly is "new" in this assembly?
- The differential case looks like it could be new, even with the few spots/stains
- Same for the differential cover; that looks pretty good minus the bushings
- The ring and pinion gears are clearly new; it would have had 3.07s otherwise
- If someone installed new gears, I'm assuming they also replaced all the bearings...what do those look like? Hopefully they were well oiled and are rust free?
- Did whoever installed the new gears do a good job on the assembly? What shop did the work? Does the red tag on the fill plug give any clues?
- The output yokes might be new since they still have stickers on them, but they weren't stored in the best conditions given the rust on the shields
- Same goes for the pinion yoke - maybe the rust doesn't look quite so bad in person? It's really only the seal shield that looks not so great, but that's cosmetic.
- The carrier/limited slip unit - there appears to be some rust on that, and that does concern me. Is it only the outer case, or are the internals also a little rusted? They really should have oiled that thing before they stored it.

Regardless of the answers to these questions, there's definitely a market for used Viper parts, as there are lots of us trying to keep these things on the road. Ebay should give you a reasonable starting place for pricing. The 3.55s will be your best selling point, as there are many owners that want something shorter out back to up the fun factor a little.

Thanks Steve. It was in a box with a label from dana aftermarket. The rear cover was also in a box with the same company label. The bushings have a red paste on them, like they were coated with something. Guy said both were bought new and never used. That's all I know, that the entire unit was bought assembled and ready to bolt in.. The yokes had plastic covers with elastic bands on them, and the axle yokes have barcode stickers on them. I think all I lack now is the exact year range these fit. I appreciate all your help.

This is where my lack of experience with earlier generation Vipers shows.

I think it would fit any Viper between 1992-2002 (Gen 1 & 2). There were some differences among those years...at some point, Dodge switched to a larger ring gear bolt (7/16" vs 3/8"), but I'm not sure when that was. It wouldn't affect which year Viper the differential housing would bolt into in that year range (1992-2002), but it would affect durability/longevity. If it's a 7/16" ring gear bolt (i.e., the thread diameter is 7/16", which you can only measure with the bolts uninstalled), the head of the bolt should take a 3/4" box end wrench. Given that there are 3.55s in there now, I'd assume they used the larger ring gear bolts.

2001-2002 Vipers came with ABS - I don't know if that affects anything with the differential though, and I don't think it does. As long as it is a 4-channel system with the ABS reluctor/tone rings at each corner (vs. a 3-channel system that would have a reluctor/tone ring inside the diff), it should have no impact on fitment.

Thanks Steve!

That looks like a Mopar Performance Diff w/ 3.55's, brand new. They were built by Dana Aftermarket. Everything there looks correct and new, just has been sitting for a LONG time.

I found a tag on the box that the rear cover was in, and it is from mopar performance parts- but its not fully readable. I can see where the sticker was on the box for the diff, but the ink is all gone. It's def all brand new. Thanks for your input, I was about to add this info to the thread. Any idea on a ballpark price- fair for both buyer and seller?

Page 170: https://www.monicattichrysler.com/pdfs/07moparcatalog.pdf