I have a NA T2 swap car, probably around 220 - 230 hp. Im running 215 tires out back, custom driveshaft, t2 trans and NA differential.

I launched the car last night at 3krpm and i hear a BANG! and the car didnt move. Now i can rev the engine in any gear and the speedo will show the speed, the drive shaft spins (sounds like it) but the car doesnt budge. Theres no weird noises that i was able to hear either.

I checked under the car and both wheels move independent of eachother and the driveshaft. When i move the driveshaft forward (clockwise looking forward) both halfshafts move a tiny bit backwards (probably just moving as much as there would be play in them) and stop. The movement is barely visible but its there.

So what did i break?


Thanks,
Jakob

 

I would say the diff, as a halfshaft broken would be more obvious (noise, busted boot and grease leakage, bearing parts, etc.). Never heard of someone breaking a diff, even an NA one. Nice. :-)

 

Sure you didnt break the driveshaft, where it is joined (I assume it is nopw a 2pc since it is custom)?

 

thats what I'm thinking.

 

I would say its the diff, but check the obvious stuff first, like the driveshaft joints. If not that, then jack up the rear end of the car, start the engine and put the car in gear. Go look and see if the drive shaft is spinning, and whether or not wheels are turning.

You can also drain the diff, open up the cover, and look at the gears and then do the steps above. There will be enough gear oil coating the parts to lube them while you run the engine for a few minutes. Click here and scroll down. This is what you should see happening. Also, check the bottom of the casing to see if there are metal fragments down there. Replace parts or diff as necessary.

Good luck

 

No it wasnt the driveshaft, it spins fine by hand, but it doesnt spin the wheels. The shaft is a 3" tube, and rebuildeable u joints done by a big rig driveshaft place.

Also if the diff was ok, the wheels would spin opposite to eachother for an open diff, together for a lsd. they dont affect eachother at all.

 

It could also be an output shaft twisted off.

 

Any reason you have not jacked it up, started the motor and put it in gear???????? Must be some reason else you would have done that long ago.

 

Ahhhhh its scary under there with tha car on and the driveshaft spinning. But i will try it tonight when my friend gets home (car is at his house).

 

And what if the diff was not ok? If you spin one wheel and the diff is shattered, what will happen to the other wheel? An open diff probably won't go opposite each other, and the lsd probably won't go in the same direction. If you say you checked out your shaft and its all good, then its pretty much narrowed down isn't it?
Personally, I think the differential gears would give before the half shaft would twist, but check it out and let us know. I got a pair of S4 N/A half shafts I'll sell ya for $45 shipped.

 

Don't put the thing in gear and try to see what happens. You've obviousy got power through the tranny and you've done this swap so you're not a dummy and you can visually verify the integrity of the driveshaft and halfshafts. If the tranny's good, the driveshaft is good and the halfshafts are good the ring and pinion is broken. Period. And by trying to put power through it you run the risk of damaging the internals further if you want to try to rebuild it or damaging the tranny if it decides to lock itself up while you're in gear. Yeah, I've had it happen and it ain't pretty. Drop the pumpkin and see what pieces fall out.

Chris

 

Well i took the halfshafts off today, it was one of those little output shafts that was broken. Had to poke the splined part that was still in the diff out from the other side, but it came out. From a quick search it seems this is that part that most often snaps.

 

You talking about the part goes from the flange into the diff housing? I have a pair of N/A half shaft, but not the flange going into the housing if you are looking for replacements.

 

Yup thats the part, i got a good one from the wreckers today, thanks tho.

 

Dude...put in a TII diff