I finally committed to this upgrade.
It took 5 hours, including 2 trips to the hardware to get the right drill bits to drill out the output flanges on the LSD diff.
The swap is pretty straight forward, I'd rate it at a basic skill level.
For anyone interested the following is the summary of steps:
1. soak all bolts that need to come off in penetrating solution.
2. Disconnect the mufflers from the rest of exhaust
3. take off the two exhaust hangars by the sway bar
3. Take off the rear sway bar
4. Take down the drive shaft aluminum cover
5. Take down the brace under the drive shaft/exhaust (mid section)
6. take out the sensors on the diff (both sides)
7. take out the output shafts/flanges bolts
8. take out the input shaft/flanges bolts
9. put a jack under the diff, with a piece of plywood to support the diff as it comes down.
10. Take out the 3 mounting bolts
11. Lower the diff, while pushing towards the front of car.
12. As the diff comes down, wiggle it to force the drive shaft to separate.
13. Disconnect the breather tube while the diff is half way down.

The install is the reverse of removal, and I actually found it easier that removal. I put the new diff on the jack, lifted it up a bit, and bolted loosely the drive shaft. I than lifted it up all the way and bolted it in.
One note, it makes it easier to install it if you take out the bolt from the back of it, and put it in once the diff is lined up.
You also don't have to take off the exhaust, I only disconnected the mufflers and let the rest hang.
Huge difference in traction off the line, and while taking corners.

 

Thanks for the info! I've been on the fence about this for a few months. I've always wondered if it would be worth it for a used diff considering the life span of the vlsd. How old was the diff you bought?

Hooking in1st with the 7at is a joke unless you feather it with the open diff! Would love to be able to floor it from a dead stop!

 

old diff



old diff



lsd in place



lsd in place
I was on the fence about doing this for the past 2 years. It is really much easier than it seems, the whole process would have taken probably 3 hours max, if I had the right drill bit. I followed someone else's advise and cracked loose all diff mounting bolts first, before I started taking things apart. Another hint, I marked each bolt I tightened on the output flanges with a chalk, to make sure I didn't miss any. Also the bolts for the output flanges look the same as the sway bar bolts, but aren't. Make sure you don't mix them up.
I bought the diff off ebay, from a car with 29K, it was $350+free shipping.

 

Sounds like some bushing updates and possibly suspension updates are in order (control arms, etc). Hooking with the power these have could be detrimental over time I would think. But would DEFINITELY be fun!

 

OP, why didn't you replace the bushings with solid poly while you had the opportunity? Those rear diff bushings are notorious for blowing out. It's a known point of failure. Granted, now you've got the experience to do this all over again, but still.

Wide 3-season rubber would probably make more of a difference than LSD. Then again, every AWD G that I've ever driven hooks up great, even on skinny AS tires. Off the line grip is one aspect of the AWD G that can't be denied.

 

I'm not looking to upgrade performance...and the replacement diff came from a low miles, Florida cat (29k). The bushings looked brand new.
I got the LSD, because of severe lack of traction the open diff offers.
A little mist, and you can't take a turn and accelerate, it just spins.
Forget driving in the snow, once you disable traction control, the car drives sideways in deep snow. One day I was forced to stop behind a bmw in deep snow, steep uphill. It took a while to get going, and I use dedicated winter and summer rims/tire combo.

 

Welp, good luck with that. From everything I've read, poly bushings on the diff introduce a negligible NVH, and only a minor handling improvement by keeping the back of the drive-train better secured. Mostly they're an OEM replacement that aren't fluid-filled.

 

How long do these vlsd's last with regular fluid changes?

 

The fluid can't be replaced inside the vlsd. It's a sealed unit within the diff housing. Heat and age are the down fall of the vlsd. 370z guys seem to wear them out faster from what I can gather. Once the fluid losses it's viscosity it starts to act more and more like an open diff.

I'm almost done wearing out the oem a/s. Looking into the s04 pole positions next.

Op sounds like you got a good diff at a good price. That's a good idea with marking the bolts. Will have to remember that