Volvo: transmissions, speed overdrive, gear ratios

Question
QUESTION: I know that over the years Volvo used several different 4-speed overdrive automatic transmissions including the AW70, AW71 & AW72.  I have not yet found anyone who can tell me what the differences are between these three tranmissions and/or if they can be used interchangably?  thanks.  duff

ANSWER: Duff,
They fit different applications, non turbo, turbo, and FD engine.  71 72 have a lock up torque converter. 70 is used in the turbo.

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QUESTION: That is very helpful.  I think, based on that, I want a 71 or 72, because I want the lock up converter.  I want to replace a BW type 35, can you make a "best choice" recommendation.  Lastly, so I do not unnecessarily bother you, is there a good online source to compare the two for gear ratios, measurements, etc?

Answer
Duff,
Either trans is good. The only place that would have specs your asking about to my knowlege is the dealer. Some of the older 700/900 series books might show that information. I do not know of any web sites that have that info. You might try www.alldata to see if the manuals they have show that info.