The Definitive Differential Thread

[ChrisWindisch]

Originally Posted by nissanNOOB

Is this something that is mostly recommended for people with the stock open diff? Is it worth upgrading from the stock vlsd if you don't track your car?

Anybody have an answer on this yet?? Worth upgrading from stock VLSD if you dont track??

-- I also have the sport pkg LSD and I was curious whether or not I would really need to upgrade if I went with 4.08 gears.

[Felix 808]

Originally Posted by ChrisWindisch

Anybody have an answer on this yet?? Worth upgrading from stock VLSD if you dont track??

-- I also have the sport pkg LSD and I was curious whether or not I would really need to upgrade if I went with 4.08 gears.

The problem with the OEM VLSD is that it easily overheats & performance falls off fast & will eventually burnout leaving you with 1 tire fire syndrome. I like solutions like the gear driven units from Wavetrac & Quailfe over clutch pack solutions which require more maintenance & most of the time special friction additives. If you are a person who likes spirited driving thru the twistys, the Wavetrac & Quailfe are great options. For competition clutch packs are more positive in their engagement & if it's a drag car nothing beats a spool.
if you are looking for more drive out of the corners, an aftermarket diff will be an improvement over the VLSD
If it had been out when I did my Quailfe & gears, I would have opted for the Wavetrac as it has an advantage as it is able to be tuned.

YMMV

[ChrisWindisch]

Originally Posted by Felix 808

The problem with the OEM VLSD is that it easily overheats & performance falls off fast & will eventually burnout leaving you with 1 tire fire syndrome. I like solutions like the gear driven units from Wavetrac & Quailfe over clutch pack solutions which require more maintenance & most of the time special friction additives. If you are a person who likes spirited driving thru the twistys, the Wavetrac & Quailfe are great options. For competition clutch packs are more positive in their engagement & if it's a drag car nothing beats a spool.
if you are looking for more drive out of the corners, an aftermarket diff will be an improvement over the VLSD
If it had been out when I did my Quailfe & gears, I would have opted for the Wavetrac as it has an advantage as it is able to be tuned.

YMMV

Well written and good points! Thanks. I live in Florida so most of my driving is in a straight line I really won't be visiting a track too often either as I want this car to last a longggggg time with little to no maintenance. I might stick with the VLSD but unsure as of yet. If I do switch most people I see are saying the Wavetrac one is the one to go with if you do upgrade!

[Taylortoons]

OK. Here is where I'm at today. Turns out the diff I bought is a manual open, which is probably better since my car is an auto open.

Install is a whole new set of hurdles. I can't find anyone in Dallas to do the work. Seems most performance shops shy away from diff/gear upgrades on the Z. Also, I called Z1 and they were less than enthusiastic about sending them the man diff and having them upgrade to Quaife and 4.08s. They also wanted the car on site so they could switch the companion flange.

I talked with Whitehead Performance in Toronto and they were very helpful. I'll ship the dif to them after the Holidays. They indicated this is not such a big deal and noted they have done several of these before. The companion flange is only $90 and can be installed while they have the guts out of the diff for the upgrade.

I am hopeful that my stock stub shafts will work when I get the diff swapped. If anyone would like to chime in and offer guidance or share their experience, that would be great.

Curious if any SES codes will be thrown when the gears are upgraded. I understand cruise control will be voided. I believe ECU Tek said they can get that back with their tune.

[Felix 808]

Originally Posted by Taylortoons

The companion flange is only $90 and can be installed while they have the guts out of the diff for the upgrade.

I am hopeful that my stock stub shafts will work when I get the diff swapped. If anyone would like to chime in and offer guidance or share their experience, that would be great.

Curious if any SES codes will be thrown when the gears are upgraded. I understand cruise control will be voided. I believe ECU Tek said they can get that back with their tune.

So your diff came without shafts? If it did come with shafts, there is no need to change them out. Anyway there should be no codes thrown after the swap. Also cruise control might work, mine does. Do a flash reset via the tap dance method, then when you start the car turn the cruise button on first before moving the vehicle. This method worked for me & I have never have my cruise not work.

HTH

[Driftomodachi]

Just be sure they adjust the lash properly or the diff will be shredded

[Taylortoons]

Yes, diff came without shafts. I have an open diff 7AT and bought an open diff 6MT. From what I have read on here, it should be a direct swap. Getting parts together now. Quaife should be here next week. I am buying the 4.08 gears from Courtesy Nissan along with new bearings, seals and flange. Plan to get whiteline bushings as well. I found a shop here in Dallas that can do the install.

Thanks for the tip on CC. I have used the tap dance method before to clear SES codes from my FI TPs.

[chops]

an FYI for people who are confused by axle stubs and what not.. if you are upgrading from a VLSD to an OSG/Wavetrac/Cusco etc you'll need an additional driver side stub (part #38220-JK01B or 38220-1NC1B) or you need to machine your passenger side stub to remove the tapered part

heres some pics that helped me figure things out pulled from nasaforums.com

a. driver/pass stub with a tapered end from an open diff or passenger stub on a VLSD (part #38220-JK01A)



b. driver side stub on a VLSD (you will need to buy one of these if you're going from an open diff to VLSD (part #38220-JK01B or 38220-1NC1B)


c. inside of the diff where the stub's lock into place

[Megan370z]

Originally Posted by chops

an FYI for people who are confused by axle stubs and what not.. if you are upgrading from a VLSD to an OSG/Wavetrac/Cusco etc you'll need an additional driver side stub (part #38220-JK01B or 38220-1NC1B) or you need to machine your passenger side stub to remove the tapered part

I didn't had any issue when I installed the Cusco LSD into the VLSD diff.

[chops]

Originally Posted by Megan370z

I didn't had any issue when I installed the Cusco LSD into the VLSD diff.

ok, not cusco then , i was just naming off LSD's that supposedly drop into the base diff

[Orestp]

Originally Posted by Megan370z

I didn't had any issue when I installed the Cusco LSD into the VLSD diff.

You have an automatic transmission - correct?

[Driftomodachi]

I have a base touring with an open diff. What stub axles do I need?

[chops]

Originally Posted by Driftomodachi

I have a base touring with an open diff. What stub axles do I need?

depends on the diff you're going to upgrade to. my picture guide above literally tells you what you'd need! read it carefully. its a bit confusing, but i explained it pretty well

[Imperial]

the Z1 differential bearing and seal kit includes a "Pinion Crush Sleeve." Is this part necessary?

[BGTV8]

Originally Posted by Imperial

the Z1 differential bearing and seal kit includes a "Pinion Crush Sleeve." Is this part necessary?

Yes