Originally Posted by cster

I put Fuchs Titan Race SYN 5 75W-90 Fully Synthetic Gear Oil in my rear diff and it was simply awful. It felt like the rear end was going to tear itself to bits once the car got up to temp.
I checked out the workshop manual for the 06 STI with DCCD and it specifically recommended a 90 oil should be used in the rear.
I then went for Fuchs Titan Race Gear 90 LS High Performance Gear And Limited Slip Diff Oil and it is much better.

Originally Posted by davefaedeen

Dont worry about it my WR1 did this when on full lock, my current RB320 is even worse almost comical when reversing on full lock around a corner (kangaroo jumps) its normal for a rally diff to do this, some are worse than others!!! its a subaru trait!! try doing it with the diff locked makes the car snake lol!!!

Originally Posted by TonyBurns

Yet neither of my A-DCCD Spec C's do or did it
I would say its down to who services it, or if in open, you could have an issue as your center diff is free, though turning "may" cause a little bit of an issue, its normally very small, it shouldnt be clunking away!

Tony

Originally Posted by ScoobyNoobie

Interesting to hear that. As I only started to really notice mine do it after the gearbox an diff oils had been changed.....

Originally Posted by Cannon Fodder

I'm going to change the oil in my rear diff for either Motul or Fuchs LSD 90 oil but is there a semi or fully synthetic rather than a mineral oil available?

I would say though that on my car the clunking was only evident after going out on a spirited drive.

Originally Posted by ScoobyNoobie

I'd say that was due to the diff getting hot, and oil thinning.

I noticed this am, as it was only 7C outside that there was no clunking. However once the car (an oils obviously) got warm, the clunking was back.

Think i'll try draining them an fitting an LSD oil.

Originally Posted by Cannon Fodder

Well that is what I am doing this weekend, I have got Motul 90 LSD oil which I believe will solve the problem.