How difficult is it to remove and replace the differential?

[Laundryboy]

I have a 2010 that I had 3.55 gears put in, now the rear end has the loudest and most annoying whine imaginable. Rather than waste anymore time with the installer, I'm going to either buy a properly set up differential or send my original to someone who has more experience installing gears. My question: how difficult would it be to remove the rear differential for a do it your selfer with a set of jack stands. Any advice or tips?

 

[georgethedog]

Do they just whine when you decelerate?

By the way, where abouts are you? Reason: there may be some people on here who may give you a good lead on a good Viper tech who can do it right.

 

[Laundryboy]

I'm located in Northern Utah. The gears whine always. If the car is moving, they make noise, reguardless of whether I'm accelerating or decelerating. I thought I might send the differential to Unitax to have them install new gears or what ever it takes to fix it, if I can remove it.

 

[VicTxV10]

How many miles on your car? Gen4 rear carriers tend to be very difficult to open after driven a while. Unitrax would be good place but so would Mark at Woodhouse Dodge. Send PM to mjorgensen.

Good luck,
Murray

 

[Sonoman]

I replaced my differential last Spring with a Visco-Lok 3.73 built by Unitrax. They've done lots of Viper rears and are very good at it. You could send your's there (SoCal), although there is about 95 pounds (with the box) to ship. I did replace it in my garage without a lift (two floor jacks, creeper, jackstands). You need to disconnect the upper control arm on one side (I did driver's) to drop the spindle far enough to allow the splined axle to pull out of the diff. If you return the toe link exactly the way it was, an alignment is not generally necessary. A shop manual is helpful-- somewhat. Knowing all the torque settings is essential. For whatever reason, threading the aluminum diff carrier in or out of position through the frame rails is the most difficult part... it just barely clears and only at the correct angle/position. I used a floor jack to assist with this part. Two sets of hands would help. The parking brake cables have to be unattached from the frame and ******* out of the way. Another difficult part: to re-insert the splined axle ends into the carrier I used a pair of short ratcheting tie-downs and carefully lined up the axle while applying pressure with the tie-down, and it went together nicely. I inserted the passenger side first and then moved on to the driver's side (which has the upper control arm disconnected from the body, allowing a lot of freedom of motion of the axle-- with the lower shock mount off as well). On the passenger side, I did not even take the wheel off.

Since you would only be doing half the job at one time (removal, send off to Unitrax, re-install later), the car would be sitting on jacks for a number of days, but it would give you a break between spending all that time under the car! I definitely recommend a padded creeper if you are going to do this-- the $30 is well spent to save your back from lying on the garage floor and giving easy mobility as well. When you disconnect the rear U-joint, the bolts should be discarded and Unitrax was good enough to send those new bolts along with the new rear end.

 

[FLATOUT]

Sorry man, I've dealt with a bad install on other cars and it's no fun. Good luck.

 

[JoelW]

I have a 2010 that I had 3.55 gears put in, now the rear end has the loudest and most annoying whine imaginable. Rather than waste anymore time with the installer, I'm going to either buy a properly set up differential or send my original to someone who has more experience installing gears. My question: how difficult would it be to remove the rear differential for a do it your selfer with a set of jack stands. Any advice or tips?

Did you break the new gear set in? When I put a new rear end from Unitrax (through JonB) they were specific about breaking the gear in carefully. I would get either Woodhouse or Unitrax to check it and redo it. Apparently the late model rear ends are difficult to get apart. You can easily do this yourself but a good 4 wheel drive shop should be able to check the setup since you already have it done.

 

[Coloviper]

Unless it is shimmed correctly, proper oil and friction modifier, you will get whine. It is not a plug and play install. They rarely are on any car, unless the entire center section is replaced. Mine took Dodge 3 times but 3rd time is the charm as it has been perfect for over 5,000 miles.

 

[Canyon707]

Well as mentioned before Unitrax is the place to get it done right. Its pretty easy to remove takes a couple hours of labor but actually pretty easy to do. I have done three o far but only on a lift. Go with a OSGiken best durability.

 

[Laundryboy]

The car has 550 miles on it, the new gears were put in at about 50 miles. I’m leaving on a family get away next week to Anaheim and thought I could just drop it off and perhaps have it freighted back to me.
The gears have whined from day one and the sound has never really changed as I have driven it.
Ok, I’ve got the car on jack stands, the aluminum belly pan is off and the drive shaft has been removed. I’ve also removed the drivers side tire. I guess my next step is to undo the upper drivers side control arm so I can remove the axle. Is that all it takes to get enough clearance to get the drivers side axle out of the carrier? Does the splined end just slide out? After sliding the drivers side out I guess I can take out the 4 bolts that hold the carrier in place and slide it to the drivers side to remove the passengers side axle? It all sounds fairly simple.

 

[Laundryboy]

I’ve got the upper control arm disconnected, the lower shock mount disconnected , the toe link disconnected and the sway bar disconnected. The spindle has a lot of free movement now, but no success pulling out the half shaft. What is the trick to getting the splines to pull out of the carrier?

 

[iownedu]

There is probly a retaining ring on the end of the splines to keep it in. Just try to pry on it a little.

 

[JoelW]

I’ve got the upper control arm disconnected, the lower shock mount disconnected , the toe link disconnected and the sway bar disconnected. The spindle has a lot of free movement now, but no success pulling out the half shaft. What is the trick to getting the splines to pull out of the carrier?

You need a pry bar to get the axle off the retaining clip. Give it a quick snap with the bar and ithe axles should slide outward from the stub. You will need to wiggle the rear end back and forth to get both axles clear. You also may need to disconnect part of the rear suspension to get it to move back and forth enough to get it out. Tie or move the axles out of the way and you can get the rear end so that one axle stub clears and then it will come out. It is like a rubic's cube. Once you get it out it seems simple but I had to cuss it a few times - that made me feel better and shamed the rear end into dropping out. It's heavy so be careful.

 

[Black Moon]

It's hard to do by yourself unless you tie everything out of the way, axles, cables, etc. I did mine on a lift and it was a pain but I don't think we disconnected the a arms. It is a tight fit but will come out. About 85#'s if I remember. Thankfully mine has been perfectly quietly since day one. JonB told me on a 355 the 500 mile break in wasn't as important as much as a few good heat cycles.

Good luck

Note: It's a Gen 3 with 355 gears from JonB and Unitrax with less than 1,000 miles on it and is for sale since going with the Paxton. Sorry, had to plug my for sale stuff.

 

[1.8t]

Will gears help you pick up any mph in the 1/4 mile? I have been thinking about a swap to 3.33's to help my car hit a bit harder down low and keep me from shifting to 4 just before the end of a 1/4 mile.

Car is an 09 Coupe w/ 591whp and 577wtq.

 

[Canyon707]

Will gears help you pick up any mph in the 1/4 mile? I have been thinking about a swap to 3.33's to help my car hit a bit harder down low and keep me from shifting to 4 just before the end of a 1/4 mile.

Car is an 09 Coupe w/ 591whp and 577wtq.

Well I guess 3:07 would be the answer then. Interesting i had 3:73 and ran out of 4th in the qtr by about a 100' With 3:55. I have a bit more to give in the quater in 4th gear. For me something in between would work best but I really like the 3.55 I assume I would not need 4th with the 3.07 but it is such a crappy gear to drive around in. I went last Saturday and ran 11.74 11.75 and 11.65 breaking out with the 11.65 go figure.

 

[1.8t]

I have gone [email protected] with the stock rear gear, but that shift to 4th just prior to the line is hurting my mph(I can't hold third and trap anything more than mid 128's even with the MOPAR PCM). I figure if I have to shift to 4th, I might as well have more tq multiplication and shift into it a bit sooner. Seems like some 3.33's would be the perfect blend between a good 1/4 pull and a highway performer.

 

[Laundryboy]

Ok, I got the carrier out, the gears have been replaced and I’m in the process of reinstalling it. It’s loosely hanging by the four bolts with the axle in place from the side I never disassembled. From here are there any precautions I should take? Should I reassemble the other side prior to torquing down the carrier? It just seems that there is enough slop in the carrier mounting bolts that maybe there is a procedure to make sure it’s lined up right. Any advice is appreciated.

 

[Sonoman]

I attached both half-shafts before torquing down the rear end mounting bolts. If you pulled the toe link on the side where you dropped the knuckle, make sure the special alignment shim didn't fall out of the frame. The diff carrier floats around a bit on its rubber mounts, so alignment isn't that critical. If the carrier is hanging from the upper mounts with the bolts in place but not torqued, there is a tendency for it to self-center. The "slop" in the other mounting points is necessary for tolerance stack-ups.

 

[Laundryboy]

Thanks for the tips. I pretty much have followed your first post in this thread to a T. I got the differential out of the car last week and took it to Unitrax while we visited Disneyland. While they were working on it I decided to go with 3.73 gears rather than the 3.55s that were in it. Devin said that the 3.55s that he removed were a cheap off beat brand and also from the residue that it had the wrong gear lube. I hope I’ll notice quite a difference. One last question, Is it true that when I torque the two upper control arm bolts that there should be weight on that side to get things to align properly?