240 transmission whining

The first thing to check is the center support bearing on the driveshaft, it's a common failure on high mileage cars.

Thank you, I have the same symptoms above 70 kph seeming to go away after a few k's (260/auto) although mine's like the noise rail wheels make when you travel alongside a train. That does sound like a very likely cause I hadn't considered.

This is probably the carrier bearing, but in cases where it mainly happens when accelerating or decelerating, it is probably the rear trailing arm bushings; worn ones allow the rear end to shift a bit, and put strain on the carrier bearing. That happened to us two years ago, and the carrier bearing was fine after the bushings were replaced.

driveshaft,

Worn trailing arm bushings will usually also cause a sagging rear end, as well as a clunk when shifting into reverse or drive with an automatic transmission. Both those and the carrier bearing are common high mileage failures.

I don't doubt you, but our 240 had neither of those symptoms, probably because I have a Keen Ear for odd mechanical noises, and it got caught early. Drives me nuts with three old cars. ;)

Not saying you were wrong, just adding some additional symptoms to look for.

Spoken like a true diplomat! Thank you for your past advice - it is still well worth reading and archiving.

just my $0.02

K.P. Canada

Thanks chaps for the pointers :-)

Graeme