'94 G50 standard vs. active rear end diff.

[qsiguy]

Did the active models come with a different rear diff or has my active Q's rear end been changed? My active has a rear diff cover that has heat sink style fins on it and my '94 standard does not. Is this only a cosmetic change or is it different?

If you need a photo of it I'll take some later.

[qship96]

I think Stillen sold this finned rear end cover, and possibly the 300zxturbo used it stock-some previous owner must have upgraded your stock one in the past! Lucky you,we need to find a supply of these for the rest of us Q owners!

[GseaQ]

Our '92 standard with TCS has the finned cover - always has.

[mtcookson]

That's interesting... all LSD equipped differentials have the finned cover that I know of. Either you have an odd ball differential or someone either put a non-LSD cover on or swapped a non-LSD differential in. I could be wrong and some of the R200V's came without the non-finned cover but I've not heard of that before.

[qship96]

Maybe someone could snap a few photos of what they consider a "finned" q45 differential so we are all comparing ours to a known standard.I think mine is ribbed,but not sure I would consider it finned? Need to take a quick look during the day!

[mxr662]

This is from a r32 unknown year1990 q45

[elwesso]

all 90-94s have the finned ones, 95 started with the non finned.. my late 94 had the non finned one, but my early 94 has the finned one. its a build date thing.

[mtcookson]

Still LSD though? That's definitely interesting.

[qship96]

all 90-94s have the finned ones, 95 started with the non finned.. my late 94 had the non finned one, but my early 94 has the finned one. its a build date thing.

Are you basing this off of just what you see on your own 2 cars? Hard to do that as who knows if prior owners ever changed diff or diff cover, especially yours Wes, with Rex and Freds history as prior owners and all the other mods completed on that specific car

[Q451990]

I remember noticing a "non finned" one on a 95 or 96 that was in the bay at T3. Dennis commented that it was probably part of the cost savings measures that they implemented in the later years.

Heath

[SATAN]

That's interesting... all LSD equipped differentials have the finned cover that I know of. Either you have an odd ball differential or someone either put a non-LSD cover on or swapped a non-LSD differential in. I could be wrong and some of the R200V's came without the non-finned cover but I've not heard of that before.

Actually, this is not the case. There are many lsd's that do not come with finned covers. This link I am posting shows a diff from a J30 that does not come with a finned cover but does come with a VLSD. You can see he switched his to the finned cover from his 87-89 300zx turbo differential. It is an impressive write up if you have time to actually read it but is a little beyond the scope of this thread. That and it applies to z31's not q45's. Or at least it doesn't apply to q45's now, we had to separate that when I started talking about hybriding the q45 diff to the Z31 lol.

http://www.z31performance.com/...=6294

[mtcookson]

Interesting... I'll definitely have to double check the function instead of looking at the cover when shopping for differentials in the future.

[qsiguy]

Here's the one in my turbo non active '94 Q. I'll get a photo of the active one tomm. but it looks alot like the diff photo above with the fins. It's also more of a silver color rather than what you see in this photo.

[silver2k2]

This is on my early 01/94 Q45a. No fins...weak

[lino]

Here is a picture of mine:

[Q45tech]

Since 90-93 lasted way beyond warranty, many things in 94 were downsized [cheapened] and weight reduced to compensate for heftiness of 94 upgrades [weight of thicker glass all around, front lights and redesign].

[qship96]

Since 90-93 lasted way beyond warranty, many things in 94 were downsized [cheapened] and weight reduced to compensate for heftiness of 94 upgrades [weight of thicker glass all around, front lights and redesign].

NONSENSE!!!The 1994 redesign went on sale IN EARLY 1993 calendar year....{which means the 1994 redesign was worked on/completed in mid/late 1992} so even the the very first 1990 Q45 sold in the USA in late 1989 was not even on the road 36 months before redesign was locked in-AND STILL IN FULL WARRANTY PERIOD!!! Lets not even consider how in-accurate that statement becomes when you factor in the 91-93 which were still almost BRAND NEW at the time of the 1994 redesign engineering was completed!!!

[AlabamaDan]

My 1994 Q with a 93 build date, non T or A, has a finned cover.

[Denver90Q]

The 90-93 was definitely built with a cost no object philosophy. I think Nissan just cheapened the 1994 to be able to compete at a certain price point not really to save weight and there were as many or more improvements made. No sure how much the fins help to cool it but I've bent or broken a number of them on my 1990 when I jacked up the rear end.

[AlabamaDan]

...I've bent or broken a number of them [fins] on my 1990 when I jacked up the rear end.

Don't be so reckless! JK Welcome to NICO.

[qship96]

The 90-93 was definitely built with a cost no object philosophy. I think Nissan just cheapened the 1994 to be able to compete at a certain price point not really to save weight and there were as many or more improvements made. No sure how much the fins help to cool it but I've bent or broken a number of them on my 1990 when I jacked up the rear end.

I fin it laughable to use the term "cheapened" when comparing the 94+ redesigngn to the original. Adding thicker glass,motorized headrests,keyless entry,color keyed switches/buttons to dash all cost money that wasnt spent on the 90-93q.

I think what really happened is Nissan realized they were getting killed in the market that heavily favored the cushy ls400, and went back to the drawing board and upgraded these cars to try to be more competitive with the Ls400....but the damage was done,and nissan never recovered from their early mistakes with the Q design and marketing {too sterile looking in/out,not enough bling.They totally mis-read the lux market in the USA at the time of introduction, whereas lexus just flat out NAILED IT.

[AlabamaDan]

I think what really happened is Nissan realized they were getting killed in the market that heavily favored the cushy ls400, and went back to the drawing board and upgraded these cars to try to be more competitive with the Ls400....but the damage was done,and nissan never recovered from their early mistakes with the Q design and marketing {too sterile looking in/out,not enough bling.They totally mis-read the lux market in the USA at the time of introduction, whereas lexus just flat out NAILED IT.

I'll agree they did some improvments as you've noted they did start eliminating some things that the public at large didn't appreciate - i.e. cooling fins on diff. We at NICO appreciate those things, but your avg lux car buyer didn't. And I can say that as a 94 owner.

[qsiguy]

Ok, finally climbed under the Q45a and looked more closely at the diff. It's definitely NOT stock. It's a Unitrax version. I don't know if this is a competely different diff or just a rebuild of the original but either way it's not OEM stock. Here are some pics

I am going to check on that model #/serial # that's on the diff to see if I can get more detail. If it's better than the one on my turbo guess where it's going?

[elwesso]

TIGHT you have a unitrax diff, i bet its a 4.08!

[sijoko]

UNITRAX is the company that did the Stillen 4.08 diffs, so that's probably what you have. The car looks it had the whole Stillen Q45 catalog thrown at it. LOL.

So far we know it has a big brake kit, NOS kit and a modified rear end. Am I missing anything?

[qsiguy]

JWT NOS ECU with the NOS kit and braided stainless brake lines. I'm wondering about the transmission. If it's been built it needs to be in my turbo.

In case anyone was wondering, I've decided to part out the Q45a. I'm going to be stripping it and some of it will be going into the turbo. The motor and a few interior parts are spoken for but I'm going to be stripping it pretty thoroughly.

I want some of the parts for my turbo and I just don't want to spend the time on fixing this one. I don't have much into the car and I can make it back in a heartbeat just in the money it will save me fixing my turbo up. The rest of the parts will be cleaned, bagged and tagged for future use or sale.

I'll probably make an official post about the part out but if anyone's interested in anything let me know. Can't promise I don't want the part you need for myself but let me know and I'll start a list.
Modified by qsiguy at 1:30 AM 3/1/2008

[gammer_ghn]

they did have a different diff. i remember reading it in an article and how stillin helped develop it but at the moment i dont remember what the article was i think it was here where i read it.

[qsiguy]

Unitrax pulled up the s/n and here's the response I got.

"Thank you for your inquiry. Unit number 28468 was built on 8/30/2005. UNITRAX ratio changed the differential to 4.08. The job required a new OEM gear set and new bearings and seals."

Sweet!

[Denver90Q]

I wonder what they charge for this service or if there is anyone who could rebuild to OEM standards. I don't think I could afford a new one.

[qsiguy]

When I pull the Unitrax diff should I/or do I need to keep the axles with it or will it bolt up to my OEM ones in my turbo? Anyone know?