There are two possible causes for your symptom. The first is low or burned transmission fluid, easily fixed by a transmission service (go to a shop that will change gasket and filter, not flush it-if you have lots of clutch material in your pan you don't want it floating around). I would also suggest Lucas transmission treatment when you change it--this will boost clutch pack pressure, which is what you are loosing when the transmission slips.
If a transmission service does not fix the problem, then you have an internal transmission issue with the overdrive gear that can only be fixed through transmission repair. Overdrive is often the first gear to fail, as it is used most often--cars often drive at 45mph in the city, and this is where the transmission shifts into o/d. So most cars shift constantly into and out of overdrive, resulting in quicker o/d failure. Quick is a relative term--it still takes years, but the cumulative result of all those shifts is premature transmission wear. For this reason, many late model cars have an overdrive off button, for use in driving around town.
Your 626 is a nice car--I really like the interiors and layout, it's feels real plush, and given the mileage, it's well worth fixing. Just make sure to find an excellent independent transmission shop before you do the work. Good luck
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Thursday, April 30th, 2009 AT 1:45 PM