This is my first write-up, so bare with me! If there's anything I missed out, or need to add anything, let me know. Please comment, criticize, give your opinions.

Tools Needed -Torque Wrench -Electric/Air ImpactGun/Wrench -Hammer -Flathead -Common size sockets and wrenches of various sizes -Medium sized tap or large screw driver (my large pry bar did the trick) -Brake Cleaner -Scotchbrite -Gasket Scraper -Gear Marker -ThreadLocker -Drain pan -Cheap thick gear oil with Motorcraft Additive Friction Modifier (Provided by FRSport.com) -Block of wood -1 or more friends

Step 1Prep the area with a long, clean, working table, with a clean table cover (large sheet of heavy duty plastic will do). -Jack up the Car -Drain the differential fluid -Once drained, place the transmission in gear and make sure e-brake is engaged. Unbolt driveshaft from differential. 4 bolts 12 or 14mm. -Remove sway bar and lower your exhaust by removing it off the hanger. (Makes your life easier.) -There are 2 17mm bolts holding the differential to the underside of the car. Loosen those two bolts, do not fully remove. -Remove (4) 17mm bolts from back of differential. -Before lowering the differential try to move the axles out of the way. -Now when you're ready take off the two 17mm bolts you had loosened and carefully lower the differential with the jack.

Step 2Bring your differential over to your working station.

-Remove differential cover by unbolting with a 14mm ratchet in a criss-cross pattern.What it looks like once it's revealed.

-Mark the axle shaft accordingly which side it came from.

-Now carefully, bang off the axle shaft with a hammer without hitting the ring gear. -Once the axle shaft is off, place them on the clean table. You could put them on the side accordingly to where they came off on the table.

Step 3 -Remove bearing cap bolts and bearing cap. Have a friend hold down the differential. -Keep the bearing caps accordingly to which side and direction it came from.

Step 4 -You can use a wrench or a pry bar, to remove the open differential. I used the wrench and hit one end with a hammer to pry it out.What it looks like once it's removed. -Be very careful, once the differential is out. Keep the Spacers according to its exact order and side.

Step 5 -With a hammer and flathead, chisel away the old gasket. I recommend to use Gasket Scraper, to avoid any seal failure.

-Do the same on the differential cover. Use Scotchbrite to remove the remaining gasket on the cover and differential.

Step 6 -Spray the inside of the pumpkin with Brake Cleaner and clean the inside the pumpkin, and on the differential cover. Dirt is your worst enemy…

Step 7 -Remove the ring gear from the open differential by unbolting the bolts with an impact gun. Have your friend hold down the open differential.Now you can start working on your new differential!

Step 8 -With the ThreadLocker, squeeze some on the ring gear bolts.

-Place Ring Gear on, and bolt in a criss-cross pattern (98-112ft lbs tq.)

Step 9 -Tomei came with axle shaft seals; so, remove old seals by hammering it out with a flat head.What it looks like once it's out.

-Hammer gently in new axle seals. I recommend using something flat to put in between hammer and seals, like a piece of wood, to hammer it inevenly.

Step 10 -With a hammer and a piece of wood, hammer in evenly the new bearing onto the new differential.

Step 11 -Your new differential is ready to go in the pumpkin. Put in the new differential, along with the new spacers provided with your new differential, and your ring spacer you saved previously. Put in the spacers accordingly to its side. -What I did to put in the differential all the way in is by hammering the piece of wood, without damaging the new differential. Make sure it goes in EVENLY. Spacers tend to tilt and move on their own. All has to go in evenly. Becareful not to hit the ring gear.

Step 12 -Place bearing cap back on, accordingly to its side. Bolt it back in with 65-72ft lbs tq.

Step 13 -Hammer in the axle shaft with a piece of wood in between, accordingly to which side it came from.

Step 14 -Place gear marker on the face of the ring gear. Rotate the shaft a few times so that it hits the marker. Make sure it hits dead on, center, of the ring gear. If it doesn't, you would need to buy adjusting shims of certain sizes to move the differential either left or right.

Step 15 -Place new gasket. -Bolt back on your differential cover in a criss-cross pattern. 12-17ft lbs tq. -Fill the differential with Friction Modifier and cheap thick gear oil.



Differential ready to go back in!

Step 16 -Jack up your differential back into your car. -Bolt back up your differential the same way you taken it out.



ALMOST DONE!



Break-In Procedure -Find an empty parking lot. -Do Figure 8 in the parking lot. Go about 10 mph on the straight away, and clutch in around the turn. When you get back on the straight away, release clutch pedal and get back up to 10 mph. Do this for 30 minutes. -Once 30 minutes is up, bring it back home and change fluid with the fluid your differential came with. -Lastly, drive for 60 miles, not exceeding the 40 mph speed limit.

My Story: LSD works like a champ. It locks in perfectly and nicely. During my installation, it started to pour, so make sure you pick out the perfect day to install it. Took us 10 hours for the whole process, including break-in procedure. Special thanks to FRSport.com.

Have fun and drive safely!-Derrick

Modified by Pho King at 8:25 PM 12/26/2006
Modified by Pho King at 10:07 PM 12/26/2006

Awesome work A++++

Absolutely beautiful write up, the best ive read on any topic.

Great write up! Very Informative.

Awesome Detailed Write-ups. Only thing, based on what I was tought, Step 5 was a No-No...

Step 5 being:

"With a hammer and flathead, chisel away the old gasket"

I was tought never to use anything metal to remove leftover Gasket, expecially if you are using a hammer as well. By doing so, you risk the chance of notching the item, in this case, the differential. If you have your smooth surface notchy, you are really risking the chance of a bad seal.

Like I said, just what I was tought, they have specific Gasket Remover Tools, Generally a non-jagged plasit chisel/scraper.

Regardless, Awesome Job..

Sweet write up, nice pics and very thorough.

Hey thanks guys! I tried to make it as descriptive and easy as I can.

Driftless240 wrote:Awesome Detailed Write-ups. Only thing, based on what I was tought, Step 5 was a No-No...

Step 5 being:

"With a hammer and flathead, chisel away the old gasket"

I was tought never to use anything metal to remove leftover Gasket, expecially if you are using a hammer as well. By doing so, you risk the chance of notching the item, in this case, the differential. If you have your smooth surface notchy, you are really risking the chance of a bad seal.

Like I said, just what I was tought, they have specific Gasket Remover Tools, Generally a non-jagged plasit chisel/scraper.

Regardless, Awesome Job..

Oh, I didn't even know there was a Gasket Remover Tools. I will add onto the writeup as a recommendation. I just chiseled away the bulky part of the gasket, scrap off the remains, and ScotchBrite it. Thanks for letting me know!

is this your first time because you gots skills anyways i heard these installation also need something called a "backlash" fix/check, i never installed it personally but its written all over on zilvia: obx Hilical review...might want to check that out

zenkii wrote:is this your first time because you gots skills anyways i heard these installation also need something called a "backlash" fix/check, i never installed it personally but its written all over on zilvia: obx Hilical review...might want to check that out

he explained it using another term, he said keep all spacers the same and check if they move, thats what the backlash is, to check if it went in right cause if some of the spacers aren't in right, the diff might/will get messed up.(btw pho king, happen to have pics of the spacers? thats the 1 thing am still tryin to learn)

nice write-up.

No problem man. Great write up, just dont want to see anyone ruin such a great investment and so much work because of a bad seal!!!

Specifically called "Gasket Scraper" if you want to look it up. Costs like $10.00 good investment.

Once again, Great work!

TheOne wrote:he explained it using another term, he said keep all spacers the same and check if they move, thats what the backlash is, to check if it went in right cause if some of the spacers aren't in right, the diff might/will get messed up.(btw pho king, happen to have pics of the spacers? thats the 1 thing am still tryin to learn)

nice write-up.

Unfortunately, I don't! I should've taken pictures of what my table was setup like...But if you're looking at the differential, at the opening, from the left axle shaft, it should have an adjustment washer that came out with the old differential. So from left to right, it should have spacer, adjustment washer, side bearing, bearing, LSD unit. And then the otherside, bearing, side bearing, spacer, axle shaft. (The right side doesn't have adjustment washer). Exact order how the old differential came out.

Driftless240 wrote:No problem man. Great write up, just dont want to see anyone ruin such a great investment and so much work because of a bad seal!!!

Specifically called "Gasket Scraper" if you want to look it up. Costs like $10.00 good investment.

Once again, Great work!

I'm glad you tell me this! So that future installer won't run into any problems!

I plan on doing a swap later and this is a good inside view of what I should expect. BTW: you should already know that aluminum is "soft" and can score easily.

Also, you should buy new bolts when you do this, the old ones have already been stretched to yield and may back out by themselves. You are probably ok since they have most likely never been removed before, but its a pain in the *** when your diff locks up because of a bolt! Thread locker doesnt always last at the temps that a diff reaches.

just weld the bolts in it will be ok............. ye yeah

wankelTII wrote:Thread locker doesnt always last at the temps that a diff reaches.

The high heat thread locker worked holding my o2 sensor in my turbo extension, never loosened or burnt off. The blue kind will burn off... but I'm not sure how hot the diff gets.

wow. this writeup is awesome. you win a prize.

ideally you'd want to have a shop press on your bearings to the new lsd, but hey if hammering them on works too, more power to it.

+1 for tomei LSD

Good writeup. I just went by the fsm on my install and it was more than enough, but some like the additional pictures.

One thing that you should add:

#X: Check gear mesh using gear indicator dye to ensure proper interaction between the ring gear and pinion gear.

After applying indicator dye to the ring gear teeth, turn the differential. A pattern appears in the dye, showing the mesh pattern. The ideal pattern shows up as ovals on the center of the teeth, with gradually fading edges.

Good gear mesh will ensure quiet, reliable operation.

The fsm explains this as well.

Visual of mesh pattern in gear dye:

BAnging Write--up LOTSA pictures too...NICE WORK .... A+++++++++++++++

I was thinking about puting a VLSD's guts in my open diff. Is it basicly the same procedure?

otterman wrote:
The high heat thread locker worked holding my o2 sensor in my turbo extension, never loosened or burnt off. The blue kind will burn off... but I'm not sure how hot the diff gets.

Yeah, the RED Loctite (272) wont burn up with the temps you'd be experiencing in a diff.

Great write up. I just ordered a Tomei Tech Trax diff for the 240. I'll follow your advice here and do it myself.

Thanks,K

Thanks so glad to see this, been digging through forums all night for some decent info.

Anyone have a list of non VLSD's that'll work w/ an 89 240? I found a post that was pretty great detailing VLSD's, but what i've read is that they can wear out in 60k-80k miles (which wouldn't be a huge loss, but takes the junkyard idea away from the stock ones)

So I guess i'm looking for a 2-way that's relatively close the the same height; though I haven't ruled out 1.5s; anyone had any experiance w/ both (primarily for drifting) to tell me what they think as a comparison?

great write up, i needed this one cause its next i think. but doesnt anyone else smoke herb and drink beer while working on thier car?????

stay away from the herb; but i'm all for some beer while working on the car.

Nice write up and install, I vote for sticky!!