Drivetrain: Install Speedfreak Limited Slip Differential Insert (LSD)

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written by Chris "Chris95RT" Semanson

We started and the only hang up we had was getting the passenger side balljoint out. After that we had the tranny out in about 2 hours. Then we got to the clutch, the clutch was replaced 20k miles ago and Ive never raced it. Thinking this I didn't know if I needed the new clutch from South bend or not.

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As you can see from the pictures, the clutch was about to fall apart... So at around 10:30 we got to the transmission and started to take it apart.


We got the end casing off that houses 5th gear and its shift fork. After that we decided to call it a night, becuase we couldn't get the entire housing off and it was 11. The next day we got 5th gear apart, and found what was holding the tranny case on, it was a reverse bolt. This is something they didn't tell us to do in the directions. So after we got that bolt out the case came right off.


Looks rather intimidating doesnt it .

If you look on the far side of that picture, you can see the place where the differential was. The gear oil also REAKed. We tried taking off the 8 bolts holdingn the ring gear onto the differential, but they were really tight so we called Jeremy up and he has an electric impact that puts out about 200 ft/lbs max. We didnt need that much. While we were waiting we bolted the flyweel clutch and pressure plate up to the engine.

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Looks pretty . Then after waiting, Jeremy came over and we put the impact to work, it took those bolts on the ring gear off in NO TIME. They had some sort of thread lock on them but that didn't stop the what I now deam the intruder.

Now that we had the differential apart from the ring gear, we noticed a few things. The large pin that goes through the diff to hold the spider gears in that is said to be notorious to backing out is held in with a smaller pin that goes through the larger pin. The concensus among all of us is that that the only way the large pin would come out is to shear the smaller pin off. The smaller pin can't back out becuase its tapered and held on by the ring gear. We put a light weld on the big pin anyways, but we couldnt figure out how that smaller pin could shear off, but I guess it does. After we put the insert in, which goes right in... with a hammer, we started work on putting the 8 bolts back on the ring gear. You need thread lock for this.


Heres a picture of an input shaft on one side of the differential to try and put some torque on it as we put the bolts back in, at 90 ft/lbs of torque. We had 3 guys holding that shaft, while one tightend the bolts down. It was rather difficult.

After the differential was put back together we started to put everything back on. The selector rods are very very tempermental especialy the one closest to the shifter. Its rather easy for that rod to come off the shifter lever. This caused us to take off the tranny case a few times to fix that. We figured we need the detents which are just silver balls and springs that hold the selector rods in place, this fixed it.

Also that reverse bolt (at least I think its called that, the bolt closest to the differential) is also tempermential because it swivvels and moves up and down. And probably the most annoying thing was figureing out the puzzle that is 5th gear. We all kept trying to figure it out, then turned to the shop manual and finaly after an hour we had it together. Do NOT take this apart if you can help it. And if you did, the shop manual tells you how to put stuff ba ck together.

The reinstall went really smooth, the tranny went right into place with not much messing with it. We had stuff together really really fast with 3 people working at it. All together, the transmission is a little daunting but dont mess with it if you can help it.

Review: I know theres a section for this but I hope Jeremy doesnt mind... The clutch is super super sweet even for a puck clutch. I cant feel any chatter, and its MUCH smoother than the stock one. I love my DXD.

The new limited slip differential feels great. Turning is a lot more responsive, there is a little more resistance to turning but its hardly noticeable. I can take turns in excess of 40 MPH with no traction issues, and luckly it rained last night really bad when I was comming home. And when I tried to take really sharp turns it kept traction. I can't tell you how it is when I burn out becuase I need to break the clutch in, JeremyC will have to tell you that when he puts his in. Overall I really like it, and I know many people have issues with the insert so I'll post back in a week to see if I can find any metal shavings in the tranny fluid.

I know everyone was curious about the insert, so this is hopefuly useful for people who are considering this.

I just wanted to add even though our Trannys arent Getrag and they arent the AWD Tranny. They still seem extremly beefy, and well built.


This will help!