i learned a huge lesson last night.

[mike13]

pay attention when swapping in a 900 dollar differential.
As of right now i have no idea what went wrong, besides the side shims or axels could have been mixed up. Everything installed perfectly and besides a bit of backlash, I thought everything was fine and ready to go.

We reinstall the diff and when we went to break in the diff it made some LOUD and disturbing noise. From all of the research i've done, i believed this was the noise that everyone describes as an unbroken-in kaaz 2 way. Well we were wrong. After a couple of first gear starts, the car wouldnt move. It was grinding like all hell, and we had to push it back onto the lift. We took the axels out and swapped them around, thinking we must have installed them on the wrong sides.

After everything was back together, we tested it by spinning the wheels, backlash was gone, and so was all of the clunking and vibration. Sweet. We put everything back together and go to break in the diff again. When i get it on the road, the diff is whining super loud. I am really worried, but figure i'll see if it quiets down after doing some figure 8's. after all, EVERYONE described crazy noises from their new diffs. After a couple minutes of figure 8's some very loud clunks and bangs occur every time the clutch engages. whenever I let off the accelerator, huge grinding noises start. We stop the car and inspect everything, there is oil dripping out of one of the axel stubs.

We try to get the car back to the garage, but putting it in gear, something is grinding really hard in the diff and the car wont move. My mechanic is laying on the ground pounding the axels into the diff and the car finally starts moving. I pull out into traffic and the diff fails, i jump out of the car and start pushing as gear oil drops all over the intersection and road.

We stop the car again, and finally get it moving, i drive straight to the garage about 100 yeards down the road, every time i let off the accelerator the grinding starts. We tear apart the diff and when we open the diff cover, there are 5-6 broken teeth from the pinion laying in the case. Every tooth on the ring gear is damaged. The diff appears to be ok.

This job was done by a professional with my supervision. The install went flawlessly and before we drove the car, i thought all was going perfect. I have no idea what went wrong, but right now i'm distressed and my car is broken. Its sitting in the parking lot with the axels and drive shaft ziptied up while i search fantically on the for sale forums looking for a new diff with ring gear and pinion.

Just let this be a reminder, and learn from my mistake. Always mark down which pieces came from where when you tear apart a diff. Even for pro mechanics this is not a simple job. Mess up one small detail and you end up with a disabled car.

Pics coming in next post.

[mike13]

we set the plates for an actual 72% locking.



broken pinion gear

grinded up ring gear.

[mbmbmb23]

Sorry about your luck man.............definately have a transmission/gear shop set up the gear lash+ shim for you after you locate a new pinion+ring set.


-m

[The ROMAN]

Damn that sucks.
I remember when I got my diff, I bitched about how the race shop was charging me $300 to install and saying how I probably could've done it myself, but it came out right the first time.
Is the mechanic gonna pay for the new parts at least?

[holisticbeatz]

Whoa.. that sucks.. I hope everything turns around for you. I've been debating on what kind of a LSD I want to get and whether or not I want to install it myself. I really gotta get my research done..

[sleep]

i have a stock open diff from my 91' with 120k sitting in my shed.......

[sykikchimp]

Well, backlash is the devil, and it doesn't sound like you guys checked the tooth engagement at all.

[S14DB]

Originally Posted by sykikchimp

Well, backlash is the devil, and it doesn't sound like you guys checked the tooth engagement at all.

Yeah, should have got some white grease and ran it thru the gears while on the bench to see the alignment of the gears.

Expensive lesson. New pinion and ring should not be that expensive but having a driveline shop do it would have been less.

[amolao]

Damn! such a sweet instal gone wrong.....I had a similar experience this weekend, but it was with a timing chain. I will make it a separated thread is a long story......

[Buffalo Daughter]

wow that fucken sucks man. I hope everything turns out all right. Live and learn. At least your cars all right so hey things will be better.

[Heartwork]

Originally Posted by sykikchimp

Well, backlash is the devil, and it doesn't sound like you guys checked the tooth engagement at all.

yep, sounds like that was the only thing you didnt check...
your pinion gear could have been totally misaligned