Dear longhorizon,

Hope you're well. The Aisin-Warner transmissions used in 940s and 960s are very hardy. The vast majority of reported failures result from failure of the in-radiator Automatic Transmission Fluid (ATF) cooler, which allows coolant to enter the ATF. I do not recall a post reporting an AW tranny as having "worn out".

I second the suggestion that you flush the transmission. See the FAQs for the flush procedure.

For this flush, I'd use Wal-Mart ATF. This is not costly: perhaps $40-45 for the 10 quarts needed. Drive for 1-2,000 miles. If there's no improvement in shifts, then consider replacing the tranny, with the sound used unit.

My guess is that fresh ATF - even Wal-Mart's product - will improve the shifts. If so, re-flush with Mobil 1 or a simiar synthetic ATF. You can then expect many more years of good service.

ATF should be flushed every 50K miles. Flushes might be done more often, if the car lives in an area with high average ambient temperatures (e.g., North and Central Africa, Central America, or the US South/Southwest), and/or which is mountainous, and/or if the car is often used for towing.

A tranny swap is best done by a transmission shop: they have all of the required tools and - because they routinely pull trannies - they can do the work faster than can a mechanic, who does not often remove trannies.

A transmission shop should be able to replace the rear main seal. Both jobs - tranny swap and rear main seal replacement - should take no more than four hours. If you go this route, have Synthetic ATF put in. Bring your own, if need be.

Hope this helps.

Yours faithfully,

Spook