driving yesterday and heard a slight BOOM, the shift **** jolted at which point thought road debris had hit the undercarriage. noticed nothing different in how the car should preform so kept going. 15 miles later heard a loud BOOM followed by grinding... pulled over to notice oil on the back bumper and a golf ball size hole in the rear diff. 3k miles ago had 4.083 final drive gears installed by JapTrix. the rear end felt good and had no disturbing humming sounds ever. am assuming on the 1st BOOM the diff exploded causing the hole.. since the car preformed, continued driving and then assuming the 2nd BOOM was a total melt down since the oil had been escaping thru the whole for 15 miles potentially. any idea why it would have exploded? do u think the stock LSD also got damaged in the process? would you recommend replacing everything in the pumpkin to stock to avoid future break downs or replace again with 4.083 and a aftermarket LSD? how much cost will b involved?

 

Wow that would have freaked me out hearing the first boom. Honestly I would take it to a dif shop and have them look at it. Just to get a un baised opinion about what happen.

Not saying anything was installed wrong just sounds a little fishy due the cituation it tore down in.


GL with the fix.

 

^ i agree, sounds to me they didnt torque a bolt or something and a bolt worked its way loose - first boom.

oh and just for next time..........if you ever hear anything/feel it like you did.......never just blow it off to nothing and drive an additional 15miles....you should have looked over your car more thoroughly....chalk it up to live and learn, but due to driving 15miles with out fluid, if that was the case, you could have more damage now than what you had at the original (1st) boom...

-j

 

I would look for an entire new pumpkin - some get sold on here quite often, and i would check your stub axles for damage as well...

but get the shop that did the install to pay if they are found to be at fault...

look for a half sheard bolt, or head of a bolt missing, etc....something had to have become a projectile to have made that hole...

-J

 

^^ +1, better go back and check out all the "debris" on the road that followed from the first boom.

 

thanks for the feedback Japtrix closed on mondays but will get it towed there tomorrow morning. hoping they are reputable and reasonable with the repair. the car is personally maintained immaculately! i trusted the quality of aftermarket parts wouldn't break so easily.

 

VO(subscribing)

 

+1

 

Spoke with Adam from Z1 Performance.. very informative guy and maybe piecing a package of parts together for a rebuild. His car has an aftermarket final drive with tens of thousands of miles and no issues. Parts may take up to 4 weeks for delivery from manufacturer! Japtrix is booked till friday but the owner sounded very reasonable to take responsibility if they are found at fault. any recommendations for the rebuild!?

 

Hey atleast z's have strong read ends. With my s2000, i used to blow diffs everytime at the track. I think i went through 5 diffs in 7 months. lol

i think the first boom was a broken tooth and second boom was that tooth shootin out through the case.

either way, good luck on the fix. and don't sniff too much gear oil. worst smell ever. LOL

 

^ no chit ! are you serious ? that bad ?

 

It's your screename that did it...



I keed..I keed.

 

why in the world would you keep driving after hearing any part of your car go "boom"???...

Note to self, if car goes boom, stop immediately and check every aspect.

 

lol @ shairf! gl bro! hope everything works out

 

Ya, s2ks are known for weak ring and pinion gears. So FI'ed s2ks usually do a rear end swap to a r200 NA 300zx diff. Its reaal expensive cuz you gotta buy the conversion kit which is around 2900 i beleive. but it wont blow up anymore.

 

haha! aftermath note to self

 

This is promising news. Keep us updated...

 

the Z was towed to Japtrix on friday. Roger (shop owner) called back later that afternoon with an update. a bolt had come loose and was flung through the rear diff cover causing the golf ball size hole. since the hole was towards the top, the oil had a chance to stay somewhat stay in the diff, meaning it was never run dry. that was the first zaboom.. and the second was the rest of the bolt getting caught on the LSD and rear cover. when he opened the drain plug almost a quart of oil was still left and one bolt came out with the cover removed. none of the gears were damage.. he cleaned everything up, placed a new cover on, and oiled up the diff. after 5k miles he wants the car back for a rear oil change. the car is giving no howling noise and driving great! Japtrix is a very reputable shop and this experience started a long term relationship with the shop. they covered everything and my only expense was the original tow from the street to my home of $100.

 

the specific cause of the problem was no lock tight was used in assembly even though all bolt were torqued to spec.

 

good to hear, hope all stays well