Apikol rear diff install today

B8 S4
#1

As others have mentioned, the install is pretty easy. I have a 6spd and noticed smoother shifts and less perceived drive train slop. I have a JHM short shifter which took out some slop, but this seems to make things a little tighter. I only did a quick drive so I probably need to drive more.

So the way this thing works is by adding the bushing and the large washer between the diff and the pressed in cylinder and by putting the counter sunk washer on the bottom to compress the rubber there. I get that it is tighter and has less play, but I am curious about the geometry of the drive shaft and the diff itself. The bushing raises the diff about 1/4 of an inch higher than where it sat on top of the OEM bushing cylinder thing. Is there any stress caused anywhere with this adjustment? I know some folks used something similar on B7s. Did they function similarly and raise the diff up? Any issues after long term use or am I just overly anal in worrying about 1/4 higher diff?

#2

Rasing the diff could change the pinion angle but its not likely to cause an issue. A pinion angle that is off by more than a couple degrees will always cause a vibration so if there’s no vibration then I would not worry about it. If it concerns you, measure the angle of the face of the differential pinion flange and the face of the Trans output flange with a dial angle finder.

Either way, tons or people running them without any problems. Since the Trans mounts sag with age, raising the front of the diff will actually make up for that slack and bring the pinion angle back where it should be.

#3

Good points. I did not think to measure the angle only how much it was raised. That being said, 1/4 inch on the diff would probably only be a couple of degrees of change.

#4

Did you install the blue or red ring? I plan on installing mine this week.

#5

I installed the red. I used ramps and then a floor jack to gently lift the diff. The diff wants to move around slightly from side to side or to the front. It took a few minutes to get it lined back up and I almost cross threaded the new allen bolt. I put some blue locktite on there also.

#6

Are there any drawbacks or negatives to this at all? Seems like a no brainer why anyone would not get this for the price.

#7

I’ve driven 2,000 miles with my red mount an zero issues thus far.