Had my 'box oil and filters changed last week - apart from making a great difference to the running of the car (speed, noise, more free-revving with less lag), I can report that it will now lock-down at 53 MPH before it gets to half-way on the temp (as I had previously reported). Last night, after sitting on the drive for 2 days, it went into final gear lock-down whilst the temp was still only around quarter-hot.
Good stuff.
Just under ten litres of Dextron IID ATF ain't the cheapest though - But in my case I'm glad I did it and it is making a difference. The mechanic said that the oil was absolutely minging and black - completely wrecked. I'm just hoping now that my car's auto box was overheating because the oil was knackered, and NOT that the oil is knackered because the box was overheating...? If you know what I mean!!
James