Disclaimer:
In NO WAY am I affiliated, paid by or benefiting from posting this information. I do not list hyperlinks or product advertisements, only my feedback to help people decide if they feel they would benefit from what I have installed in my own car.

Differential:
Limited Slip Differentials, what many of us consider to be the most expensive non-power adder (after install) aside from wheels, suspension or other cosmetics. For true front wheel drive motorsport fans nothing disperses your vehicle’s power more efficiently than an LSD. Mounts, bushings and braces may help gain traction and reduce wheel hop but I feel these components should be used to fine tune traction after an LSD unit is considered. One thread provided some great reasons for an LSD including the release of the AWD Golf R, wheel-hop and traction loss. I want to also pay homage to the -SHOP AND MOD REVIEW by Allset: TYROLSPORT & PELOQUIN's LSD- thread and -JoeVDUB’s USP steel shift forks- thread. Aside from the LSD I knew it was an opportunity for some preventative maintenance as I was at 30K miles.

Choosing an LSD Unit:
I’m not going to head into the details here or the mechanics behind an LSD but rather review the unit I chose and how I feel it changes the characteristics of my vehicle. I considered three LSD units, Peloquin, Quaife and the latest Wavetrac release. Peloquin has been around for a long time, is a one man shop here in the US, and has been noted across many Audi/VW forums. The Quaife unit has also had nearly the same amount of positive feedback. The Wavetrac unit has some amazing patented benefits, a great comparison to the first two units but has not been proven long term yet. After talking with Peloquin (Gary) over the phone and reading countless threads I decided to go with a high quality unit which has been proven time and time again. If you read the history section on his website, it’s clear why he’s been in business so long. The shipment included the LSD unit, bearings, ARP bolts and shims. The LSD is truly a work of art, heavy as hell and a clean piece of mechanical magic. I almost felt bad installing it in my car, as though it deserved to be in a glass encased pedestal in my man cave. The shipping was fast and packaging was top notch.

Shift Forks:
Hearing how some of the high mileage MK4’s and MK5’s had brass shift fork failures, I wanted to upgrade to the USP Motorsports 1st-2nd & 3rd-4th steel shift forks while swapping out the supposed “lifetime” VW transmission fluid for Motul Gear 300 SAE 75W90 transmission fluid. From what I’ve read and seen in person, the weak brass forks experience broken claws and are held together with rivets vs. welds. I wanted to upgrade them and resolve the potential problem ahead of time. These steel shift forks are an upgrade to the brass failure points and the problematic riveted assembly by way of a more durable welding process.

Supporting Hardware:
New axles, CV transmission seals, clutch, throw out bearing (latest revised part number 0A5141671F with 1-piece slave cylinder), NLS 02Q throw out bearing shims, Audi S3 short shifter, USP Motorsports stainless steel clutch line and ATE Super Blue 4.1 brake fluid were recently installed so I felt the transmission had been thoroughly covered for future power additions.

End Goal:
My end goal was to build an “awesome daily driver” (low NVH, heavy power on demand, safe for the average enthusiast). I’m personally looking to strike a fine balance between a baby daycare shuttle during the week, spirited mountain warrior on the weekends and then an occasional HPDE track car. I'm trying to increase some stiffness, correct or improve suspension geometry, improve traction, and realize better overall response from driver input while limiting NVH, rattles and feeling beat up from long drives. I spent too much time building my perfect build on paper, ultimately knocking out part by part and knew that one day an LSD was on the list. My concern was for usable power thus correct suspension, transmission and tire choices are a must. My future plans include Bilstein shocks & struts for my DG springs, Passat/TT LCA’s, TT LCA bushings, Continental DW tires and finally a big turbo kit to finish it off.

Simulating an LSD:
Originally, I came across some helpful TSI / 2.0T threads such as -Michal’s ESP, XDS, DSR, ASR, Brake Assist, Hill Hold Control Settings Vag-Com- thread, -Carsfeverguy’s XDS Settings WOW!!!- thread and -Veedoubleme’s VAG-COM - Torque Steer Compensation-thread. These threads discussed VagCom settings called XDS and ASR which attempted to replicate the effects of an LSD.

ASR (Anti-Slip Regulation), detects wheel slippage and applies braking force to that particular wheel. Working with an Electronic Differential Lock at speeds below 25 mph, ASR controls throttle response to maximize traction and minimize slipping for enhanced driver control in tight cornering situations.

DSR (Driver-steering recommendation), an additional function of the electronic stability program (ESP). This function indicates to the driver in critical situations by means of slight steering wheel impulses the direction evaluated by the system, in which the vehicle must be steered, so that it stabilizes. The driver-steering recommendation is active when braking sharply on different road surfaces and on the right and left vehicle side.

XDS, an advanced electronic differential lock, linked to a ESP system. In moments of fast cornering XDS gives out exactly the right amount of power, providing pressure on the inside wheel to prevent wheel spinning. The result is better traction and a reduction of any tendency to under steer.

The Torque Steer Compensation (TSC), only being activated for Front-Wheel-Drive (FWD) Mmdels which have a high powered Engine. This function prevents the Car from leaning into one Direction while Accelerating in Combination with powerful Engines and unequal lengths drive shafts.

From the factory this setting is at 0, some have tested a value of 1 (moderate) or 2 (strong) after learning what the UK Scirocco is set at. I tested the XDS value of 2 but didn’t feel any more confident going into a turn and definitely did not gain traction. I didn’t even want to experiment with the ASR. With the installation of an LSD, I wanted to reset all factory settings. Could there be a benefit of adjusting some of these settings with an LSD installed? Possibly, but I’ll wait for proven results.

The Install at Redline Speed Worx:
The LSD + installation is a heavy bill to swallow all in one shot. Luckily, Redline Speed Worx (RSW) has recently started offering GE CarCareOne 0% interest financing options (lifesaver near the holidays). JR at RSW has done countless transmission rebuilds and LSD installations. Before starting he laid out all the parts and required tools for an organized installation. He drained and removed the transmission, opened the transmission case, cleaned all components and transmission case in a special enclosed wash tub, visually inspected the internals, disassembled the current OEM differential, assembled the new Peloquin limited slip differential, reassembled the internals with the addition of the USP steel shift forks, sealed the transmission case, re-installed and filled the transmission with Motul Gear 300 SAE 75W90 transmission fluid and bled the clutch line with fresh ATE Super Blue 4.1 brake fluid. Overall the installation ran the full day but it was reassuring to see that JR and Redline Speed Worx spent the time to visually inspect and wash the internals in a solution so everything was re-assembled with care. A part of me feels like I received a freshly rebuilt transmission.

The End Result:
After JR bolted everything back together he took me for a test drive to explain the dynamics and what to expect. He flipped ESP off and pulled out of the shop and into the rain. He tried to break the tires loose but even with snow tires in the rain, we experienced gobs of traction. Leaving the shop I kept ESP off and drove easy on the way home. Immediately the transmission seemed smoother with less noise and shifting was also much smoother, most likely a result of the fresh Motul transmission fluid. The USP Steel Shift Forks did not change the feel/weight/engagement of the transmission, one would be hard pressed to notice a difference. It’s just good to know this preventative step could save me from higher repair costs down the road. On a few side roads I moderately tested straight acceleration from a stop (with my new axles I won’t try full WOT holeshot launches). Wheel hop was gone, torque steer compensation held fine at the factory setting without any increased intervention from the ECU. The steering wheel feels tight and settled during acceleration through a straight away or turn. Around tight turns you can feel the front inner tire gripping and clawing away. Between this Peloquin LSD and certain upgraded mounts it feels like this car can apply close to 100% of its drivetrain power to the ground, making it feel even faster. Since owning this car, I have never wished for snow, but now I can’t wait to romp around to see how it reacts!

After a few more weeks of testing I can say that this Peloquin LSD has forever changed the dynamics of my car. Hard starts, high speed on/off-ramp entries, tight turns, wet pavement are no longer a terrifying concern. As front wheel drivers, we negotiate turns, braking and acceleration based on the limitations of our setup. With an LSD your negotiations change for the better. Entering and exiting on/off-ramps at high speeds does not require as much braking and a driver can more confidently hold down the throttle into the turn. Originally I would brake to slow down and coast on the throttle to make it through the turn, find the straight away then hammer the throttle to accelerate. Now I find myself braking less and powering through the turn and actually accelerating at times. When accelerating and turning from a stop, the car grabs for traction no matter how tight the turn. On a hard launch (ESP off) the car claws at the road, keeping the car straight and sometimes flipping the power back and forth between both front wheels to gain the best traction until both tires are settled. The confidence increase is amazing, there is a sensation of pure control and a closer link between man and machine. As many have said, the front wheel drive GTI should have come with an LSD from the factory. If you can afford one, I highly recommend adding this to your already upgraded vehicle or adding this before you decide to go with a big turbo kit.

 

After a few more weeks of testing I can say that this Peloquin LSD has forever changed the dynamics of my car. Hard starts, high speed on/off-ramp entries, tight turns, wet pavement are no longer a terrifying concern. As front wheel drivers, we negotiate turns, braking and acceleration based on the limitations of our setup. With an LSD your negotiations change for the better. Entering and exiting on/off-ramps at high speeds does not require as much braking and a driver can more confidently hold down the throttle into the turn. Originally I would brake to slow down and coast on the throttle to make it through the turn, find the straight away then hammer the throttle to accelerate. Now I find myself braking less and powering through the turn and actually accelerating at times. When accelerating and turning from a stop, the car grabs for traction no matter how tight the turn. On a hard launch (ESP off) the car claws at the road, keeping the car straight and sometimes flipping the power back and forth between both front wheels to gain the best traction until both tires are settled. The confidence increase is amazing, there is a sensation of pure control and a closer link between man and machine. As many have said, the front wheel drive GTI should have come with an LSD from the factory. If you can afford one, I highly recommend adding this to your already upgraded vehicle or adding this before you decide to go with a big turbo kit.

The Pictures:




Peloquin LSD Packaging:



Peloquin LSD Hardware:


Peloquin LSD Unit:



USP Motorsport Steel Shift Forks Packaging:


USP Motorsport Steel Shift Forks:





USP Provided a New Transmission Seal / Cap with the Steel Shift Forks:


Full Parts on Shop Table:


Draining and Removing the Transmission: [/B]



JR After Eating His Wheaties:


Getting to Work, Transmission Disassembly:


02Q Transmission Internals:


USP Motorsport Steel Shift Forks vs. OEM Bronze Shift Forks:


OEM Bronze Shift Fork Failure Points:
[IMG]http://img545.imageshack.us/img545/997/img1012kw.jpg

 

Dirty Transmission Case @ 30K Miles:


Cleaning the Transmission Case:


Clean Transmission Case:


Internals with USP Motorsport Steel Shift Forks:




Drilling Out the OEM Differential to Remove Ring Gear:


Installing the OEM Ring Gear on New Peloquin Limited Slip Differential:




Measuring New Peloquin Limited Slip Differential in Transmission Case:




Sealing the Transmission Case:



Fresh Motul Gear 300 SAE 75W90 Transmission and ATE Super Blue 4.1 Brake Fluids:

 

Just wanted to circle back as the Northeast had a few inches of snow/sleet/rain. The LSD with the snow tires handled like a champ. Cars were overshooting their turns and sliding out all over the place. I tested the throttle to see how much power I could put down before the traction control kicked in. I was surprised to see that I could get on the power more than I have in the past without traction loss. The car clawed its way through the chunks of snow, slush and water. I definitely felt more confident driving around the back roads of my area.