How to install a diff in your GEN II

[Boosted Motorsports]

In this video I show how I changed the differential in my Viper to a Mopar Performance 3.73.

Install is pretty straight forward and would be much easier with a lift and power tools but this video shows that it can be done in your own garage.

Check back on YouTube for more videos uploaded every few days! In car review video also coming soon once gears are broken in but so far it is a HUGE upgrade to the car and my most favorite mod yet. ;)


https://youtu.be/l4GzvLueOqs

[My98RT10]

Awesome video, thanks a lot for sharing! I've always wondered how heavy the diff is? Seems like you can hold the weight alone and don't need second person...? I still have this project ahead of me.... will do 3.55 though...

[Boosted Motorsports]

Awesome video, thanks a lot for sharing! I've always wondered how heavy the diff is? Seems like you can hold the weight alone and don't need second person...? I still have this project ahead of me.... will do 3.55 though...

It definitely isn't light and had a buddy obviously giving me a hand but only one of us could fit under there at a time. I used the floor jack with a block of wood to throw it back up there and i guided it up. Only fun part is manipulating the diff to get the "batwing" to clear the 2 frame rails as it is much wider than the space given.

Unless you are going forced induction don't bother with 3.55. The 3.73 is not excessive whatsoever and makes the car much quicker and fun to drive. I'm actually dreading when I upgrade to new wheels as my gear ratio will effectively be around 3.55 and not be as good as it is now...

If you have ever driven any performance sports car with a good transmission gear ratio the 3.73s feel right at home.

[My98RT10]

I have the gears already so will stick to 3.55 I guess...

I do have a few more questions, if you don't mind:
- how hard was it to loosen the 8mm bolts of the drive and half shafts?
- could you reuse them or did you take new bolts?

Thanks again, looking forward to your review once broken in...!

[Chris1]

It definitely isn't light and had a buddy obviously giving me a hand but only one of us could fit under there at a time. I used the floor jack with a block of wood to throw it back up there and i guided it up. Only fun part is manipulating the diff to get the "batwing" to clear the 2 frame rails as it is much wider than the space given.

Unless you are going forced induction don't bother with 3.55. The 3.73 is not excessive whatsoever and makes the car much quicker and fun to drive. I'm actually dreading when I upgrade to new wheels as my gear ratio will effectively be around 3.55 and not be as good as it is now...

If you have ever driven any performance sports car with a good transmission gear ratio the 3.73s feel right at home.

Very nice video. Does Mopar make the 3.73 Performance Rear for a 96 RT/10 as well? That seemed like a pretty straight forward removal and installation, except for the exhaust. lol.

[heath1225]

I just bought one as well!

[dave6666]

Awesome video, thanks a lot for sharing! I've always wondered how heavy the diff is? Seems like you can hold the weight alone and don't need second person...? I still have this project ahead of me.... will do 3.55 though...

Did mine diff swap by myself. No need for a helper.

[dave6666]

In this video I show how I changed the differential in my Viper to a Mopar Performance 3.73.

Install is pretty straight forward and would be much easier with a lift and power tools but this video shows that it can be done in your own garage.

Check back on YouTube for more videos uploaded every few days! In car review video also coming soon once gears are broken in but so far it is a HUGE upgrade to the car and my most favorite mod yet. ;)


https://youtu.be/l4GzvLueOqs

So what does the "Mopar Performance 3.73" come with? Is it just gears, or does it come with a better LSD than the stock Dana one? Which if you've changed it you'll notice the lackluster performance of the Dana LSD.

[Boosted Motorsports]

I have the gears already so will stick to 3.55 I guess...

I do have a few more questions, if you don't mind:
- how hard was it to loosen the 8mm bolts of the drive and half shafts?
- could you reuse them or did you take new bolts?

Thanks again, looking forward to your review once broken in...!

- The 8mm bolts have (insert age of car here) old loctite on them so they could be a bit of a pain to remove but didn't cause me any issues. Make sure you have your wrench/socket fully on the bolt head when cracking them loose to avoid rounding.
- Common opinion is to replace the U-joint straps with new whenever being removed. Some people re-use but it known to be a failure point if you do.


Very nice video. Does Mopar make the 3.73 Performance Rear for a 96 RT/10 as well? That seemed like a pretty straight forward removal and installation, except for the exhaust. lol.
Yes 96-02 uses this exact same diff. I know some people said 96 was an odd year for RT/10s with being a "between generations" year but someone else may know better on this.



I just bought one as well!

Nice!!! Let me know how you like it!


So what does the "Mopar Performance 3.73" come with? Is it just gears, or does it come with a better LSD than the stock Dana one? Which if you've changed it you'll notice the lackluster performance of the Dana LSD.

DC chimed in on a previous thread and said it is still the factory LSD except has the upgraded 01-02 larger carrier bolts for better strength. Might look into a better LSD in the future as you said!

[98RedGTS]

Thanks for the video and the quick BC review as well. Removing the Diff actually looks more straight forward than I was thinking it would be.

Question though - Did you give up on trying to locate polly bushings for it? Looked like you installed everything back together with the factory ones still in place.

[My98RT10]

At 2:23 in your video you are loosening (removing??) the center bolts that connect the diff to the pinion crossmember. But obviously you removed also the pinion crossmember from the frame as could be seen later in the video. So was it required to loosen these bolts at all to take out the diff?

I am just wondering, what is the best way to take out the diff and if the pinion crossmember needs to be removed from the frame or can stay where it is....!?!? Thanks!

[BrianACR]

Great video!! Again :)
Just wondering when you're gonna do the 'how to install a lift in your garage' video? Lol :smilielol:

[Boosted Motorsports]

Thanks for the video and the quick BC review as well. Removing the Diff actually looks more straight forward than I was thinking it would be.

Question though - Did you give up on trying to locate polly bushings for it? Looked like you installed everything back together with the factory ones still in place.

You're correct! Luckily they seemed to be in decent shape for now so I didn't bother at this time. I heard someone say they tried Energy Suspension bushings for the C4 vette in the batwing but they got pounded out quickly. Not sure how true that is or not. I did actually take measurements of the bushings that are in the diff mounts on all 4 which I may do some research on. I don't feel like taking that diff out again anytime soon though without a lift lol.



At 2:23 in your video you are loosening (removing??) the center bolts that connect the diff to the pinion crossmember. But obviously you removed also the pinion crossmember from the frame as could be seen later in the video. So was it required to loosen these bolts at all to take out the diff?

I am just wondering, what is the best way to take out the diff and if the pinion crossmember needs to be removed from the frame or can stay where it is....!?!? Thanks!

Good eye! I did begin by loosening those bolts but they have a nut on the top that you have to get a wrench on. You could just stick your hands up and remove the two rubber mounted bushing bolts which we ended up doing. I was just trying to save having reach way up to those rubber mounts but I ended up doing it anyway.

On this note I would also leave that mount loose on the diff during install. There is quite a bit of play from that mount->diff and I didn't want to be fighting it while putting the diff up in the car. Once all the bolts on the rubber mounts were in and tight, I then tightened up the mount->diff.

In your case if you are re-using your diff then you dont have to remove that mount if you want to avoid doing so. With me swapping diff housing it had to be loosened anyways :D


Great video!! Again :)
Just wondering when you're gonna do the 'how to install a lift in your garage' video? Lol :smilielol:

Hopefully sooner than later Brian! :D At this rate though is there anything else I need to be under the car for? lol

[heath1225]

Doing this swap tonight! Wish me luck.

[Boosted Motorsports]

Good luck! It honestly isn't all that hard it is just a bit time consuming doing it on the floor. Hardest part is manipulating the bat-wing diff cover through the frame rails but just push one end really high up to the top of the var and you'll make enough room.

Let me know how it goes!

[My98RT10]

Have fun!! ;-)