mx5cartalk.com

Here's the story, I was driving home the other night, and stopped at an intersection to give way. Took off a bit quick and the road was wet. Got a bit of wheelspin and suddenly a chattery grinding sound would be the best way to describe it, backed off straight away of course and drove home very carefully. Anyhow, I take a look under the car and see that one of the big bolts that hold the diff to the PPF has started to back out. So after tightening them up and getting a good 80-100 ft/lb of torque so they don't escape, I drive off the ramps and the back end is making new nasty noises. It is a real clunk, which is there forward or reverse, in gear or coasting. I still have drive (but obviously don't want to drive it in this state).

What is the most likely scenario? Have I lost a couple of teeth of the crownwheel and pinion? What else breaks on a torsen? This one did have some wear on the gear faces.

john

Well, not the diff this time it turns out.

I crawled back under to see if the uni joints were making noise, it seems I was missing the aluminium block that sits on top of the diff carrier and holds the splined nuts for the two long PPF bolts, and as i tightened the PPF bent enough to hit the propshaft flange. It seems one of the bolts is damaged however, as I cannot get it out with the diff and PPF still in the car. On top of that the little cast iron spacer that sits on the lower side of the diff carrier that the bolts run through is cracked anyway. Ah well, pull it all off the road for a couple of weeks (replacing the diff as it a bit noisy anyway) and take my time.

john

You may not have killed the diff but may certainly have killed the PPF.

Ouch. PPF is F.

http://www.mx5mania.com.au/product1524.htm

sorry to go off topic, but wondered what are these spool diff centres?

I'll have a go
it locks an open diff completly without the LSD centre

fantastic for the racetrack. Illegal for road use

so it pretty much is a cheap alternative to an LSD?

for a race car yes. for a road car not really there is no slip. it is a solid rear end.
lsd have limited slip for corners. this is locked up all the time so there is no slip.