Any Advice?

[Clifford Pope]

Originally Posted by john.wigley

Having said that, if it has to be a manual try and get one fitted with an overdrive - I've had two, a 145DL and a 245GLT. In my view they were nicer to drive than those without - quieter and more refined at speed, and 10 - 12% more more economical overall when driven like for like.

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I agree the plain 4-speed seems lacking, but the M46 and M47 are pretty much the same regarding economy etc?
I did once long ago convert an M47 to a M46 just because I'd experience of an overdrive box on other cars and loved the slick clutchless change. I haven't bothered with my subsequent cars - the 5-speed seems pretty good - but I've kept the old 4+OD together with the prop shaft just in case. The 5-speeds don't have the longevity of the earlier box, and start to get noisy after about 200,000 miles.
The overdrive box did about 450,000 miles when I scrapped the car, but still seemed faultless and good for another few.