Originally Posted by E36graduate
Put in Royal Purple Synchromax.
The sound is the same as when you shut off the car without pushing in the clutch. Chatter.
And that's your problem. RPS lasted about 2 days in my car - and I went back to BMW's LT2 fluid. The RPS is thinner then is supposed to be in these transmissions.. while that makes them shift easier, it also allows the bearings to make more noise, and the gears to rattle.
Put stock fluid back in. Your transmission will thank you. Sometimes the hot-mod isn't really such a good idea - and this is one of those cases IMHO.