My OEM differential is under suspicion for being faulty, as well as clunky and irritable , and I was considering replacing it with the Quaife Helical Diff. I was wondering if some of you have made the transition and how your experience was with the installation and operation of the unit? Are you happy with it? Is it as smooth as they claim? Where did you go to have it installed? Thank you

 

I'm going to be installing this differential also; I ordered it in early December and am expecting it to be delivered sometime around the end of the month. I plan on having forum member motorcarman install it in his shop. While I have no experience with it yet, I've been told that these differentials are the best money can buy. Forum member avos was very helpful when I was researching this mod; you should talk to him.

Mark

 

The Quaife unit is very good and strong, no doubt, and easy to drive.

Key is that you need a diff expert with patience to do the Job well, as the tolerances/preloads must be right or you risk losing your diff (can be in a short or longer term). This is basic difff rebuild and has nothing to do with the Quaife unit.

Personally I just favor clutch type diffs, and am currently using the os giken tcd (developed for the Nissan GTR), only drawback is its price…

 

I noticed on their website they reference only MY2006+ XKR's, but perhaps that's only for a particular kind (QDF3W). Which type did you order? I imagine it would be compatable with the 2002 XK8.

 

I'll ask the shop here what they think about installing it. What's the cost of a Quaiffe diff? I checked their website but they don't list them? What's your opinion of the oem diffs in the XK8's?

 

I ordered the QDF5W, which specifically states that it's for MY 1996 - 2006, from the following web site:

Part Number QDF5W

They were very professional and had a good price; better than I was quoted by other sites.

Mark

 

Quaiffe quoted me around $2k but Pro Street, from the link above, lists them for $1450 and states that they fit all Jaguar XK8 models.

Mark

 

Good find! Considering a rebuilt oem from motorcars is $1,005 I'd say $1450 is a very good price considering the new technology.

 

This surprises me. Do I understand that in addition to all the 4.0 engine problems, wheel bearing problems, ABS irritation and conv top green shower problems that Jaguar didn't even put in a differential that would last the reasonable life of the car? This is amazing to me. What else is looming in the wings with these cars?

EZDriver 95 XJ6 2000 XK8

 

No, I do not believe that there is a reliability issue with the stock differentials. I'm sure there have been a few failures but mine, for instance, is fine. I'm changing it because I want a limited slip differential. I will also be changing the rear axial ratio from 3.06 to 3.27.

Mark

 

very VERY few differential failures or problems have been reported on the forums in my tenure here...maybe a few, if that many.

 

Sorry Guys. With all the other problems I just assumed that when different differentials (no pun intended) were being installed the omes' were failing. Shouldn't assume. Makes an *** out of u and me. Or at least me.

EZDriver

 

I just got my 2002 XKR back from motorcarman with the Quiafe LSD and a new rear axle ratio (3.27 vs oem 3.06). I can really feel the difference, it pulls very strong during acceleration through 70 or 80 mph (as fast as I've tested so far). Also, with the LSD, I no longer "cherp" the rear tires when taking off. I'm very happy (thanks Bob).

Mark

 

You are very fortunate to be close enough to get Motorcarman to do the dirty deed.

No TCM problems with the move to the 3.27 ratio? That's on the Mercedes based transmission?

 

I had a new TCM for a 3.27 axe ratio.

Mark

 

Nice to know that such an animal exists.

 

Jaguars sold in Mexico come with a 3.27 rear axial ratio to compensate for the lower quality gas common in Mexico. At least that's what I've been told.

Mark

 

The TCM for the 3.27 final drive had the SAME 'last 3 digit VCATS' as the original 3.06 TCM so it was 'plug and play'.

bob gauff

 

The TCM he used was reprogrammed thru Eurotek in New York. He sends them to Germany to be modified.