Suby's often suffer piston slap when cold, but shouldn't do it hot.
They also suffer noisy lifters, seemingly more so than other engines.
Noisy lifters can be caused by a life of crap oil. If you pop off a valve cover and things look black then it's had crap oil. It will have sludge through-out the motor that tends to block up the fine oil pathways in the lifters and makes them noisy or collapse completely.
On my V6 it had noisy lifters to start with, when I used 20W50 oil in it. I looked around the MX6 forums and they all said to run 5W30 synthetic. I made the change and the noisy lifters went away. Sometimes I get 1 noisy lifter when the engine is cold, and that's usually when it's about time to change the oil again.
Wes -
www.offroadvw.net - 200HP Quad Cam V6 in a VW Baja - with climate control...
🙂
www.taylorcycles.com.au - My DH MTB racing brothers shop.