D4 SDV6 rumble low rpm high load 5th/6th gear

Update.

I checked the fluid level in gearbox, which started overflowing with sump at 35deg, so that was ok. Actually had to run through the gears three times before the temp rose from 30 to 35 degrees.

I put a tube of dr tranny in at the same time, as this was the only idea I had to affect the gearbox...nil change to sound though, although it actually seems to slip slightly more now, not in a bad way.

The weight attachment is not progressing at the moment, as the hole (threaded according to the bulletin)is not threaded and needs to be taped first and I don’t have a 10mm tap.

Indy agreed with idea of dr tranny to see. Drove it for a bit and felt strongly that it was a driveline noise and not engine related. I had front diff replaced due a whine, but the sound remains. In the plus side, the level of luxury jumped up quite a bit with the new diff!! [emoji16]