I recently had a Quaife Limited Slip Diff installed in my '04 E55. The install (along with all other mods) was performed by HP Autowerks in Santa Barbara. The quality of their work and attention to detail is magnificent.

Car stats/mods:

2004 E55
25k miles
Renntech pulley/ecu/headers(coated)/K&Ns/Upgraded IC pump/stock shyt Contis

The first day I had the car back, I was just kinda' cruising it around. Mainly because there was crummy traffic everywhere. The main thing I noticed from the diff, wass that there was nothing to notice. No popping or clunking on sharp turns or driveway transitions like some diffs I've had. There was no "dragging" of one tire on sharp turns or ANYTHING to give away the fact that something had changed. What I DID notice was that upon leaving driveways or making right turns that required moderate acceleration (merging into traffic) there were no issues with the ESP hamstringing me and leaving me like a sitting duck in traffic. As a matter of fact, this has yet to happen in ANY circumstance since the LSD was installed.

Day two: It rained SO F-ING HARD I thought about buying a canoe to go play in the front yard. . . . perfect LSD test weather though. Mild (normal) driving was perfectly uneventful, even with the ESP off. When the throttle was squeezed just enough to break the tires loose, the car was VERY predictable and controllable, although the rearend DID have the tendancy to move left or right (usually left). Still though, it was very smooth and controllable. No shocks or surprises. Normal to slightly aggressive driving (for the weather conditions) with ESP armed showed little-to-no activity from the ESP and very smooth, stable driving.

Day three: The weather was perfect so I acted the hooligan a little. With ESP armed the car will still turn the tires, causing throttle-cut, but recovers VERY quickly. With ESP off, the car will turn the tires very hard, but not simply blow them away. It maintains constant, strong acceleration even when spinning. If the wheel speed gets too out-of-control (vs. vehicle speed) the car has a tendancy to step right or left a little. This is easily correctable with a little throttle modulation. ESP armed and normal driving, the LSD is seemless and you can't even tell it's back there. Perfect.

Conclusion: Quaife's LSD for Mercedes is a success in my opinion. It does what any MBZ part should do best; be seemless and invisible to the driver. The LSD behaves like it's been there all the time and truly enhances the drivability of the car. It also rid my car of one of my worst pet-peeves: the annoying driveway-exit/right-turn ESP-stall. My only words of caution would be to be careful once you first get in the car from doing this modification. Don't pull right out into the street and try to do a big, smokey burnout. The car now behaves like it SHOULD, not like a forgiving, peg-legged sedan. It WILL swap ends on you if you act like a clown.

Disclaimer: I have no affiliation with MBZ, Quaife, HP Autowerks or Renntech. All testing was performed with NO traffic, children, bicyclists, endangered animals/plants, or any other cute, helpless 'things' nearby and in as safe a manner as can be reasonably expected by an experienced and sane individual.

 

Thanks for the comprehensive review, I am in the process of getting one now. Please tell me that you did not have to send your rear-end to them to get the work done.

 

Everything was done at the shop where I left the car. Nothing had to be shipped out anywhere to be worked on.

 

Nice review...you shaould have posetd also in E55 forum...

What is Qualife LSD locking rate ???

 

Thanks, I didn't want to cross-post it and I figured everyone would look in here anyhow . . . maybe not.

I don't know what the bias is on this unit. You'd have to ask someone from Quaife.

 

has anyone tried one of these in a sl55? thanks

 

Great review. Thanks.

If you don't mind me asking, what was the cost of the unit, and how many labor hours did you pay for?

It amazes me that they don't offer LSD in the E55.

 

Quaife was $1615 plus about $50 in misc. seals and fluid and $1200 for install.

 

1200 for install..sounds a lot...

 

the quaife is just a limited slip and not adjustable on accel or decel like some of the others-unless they changed them and i'm not aware of it

 

The amount of labor required is quite serious for this install.

 

I was very interested right up to the $1200 install point.

 

Same here. That dropped the diff down below the stabilizer bar and springs on my long-term "to do" list.