Hello,I drive a 1993 Cadillac Fleetwood which now has 175,000 on the clock. It still looks and runs great and provides comfortable, reliable transportation. Last year, I had the transmission serviced at a local garage. I asked them to drop the pan, remove and replace the filter, and refill with Amsoil brand transmission fluid, of which I have heard many good things. There was nothing wrong with the transmission when I brought it in for service and there is nothing wrong with it now. It still shifts smoothly and doesn't slip. The cost of the service was $65. OK, here's my question! If I am interested in getting maximum life from this transmission, would it be a good idea to have the same transmission drain, filter change, and refill service done every year from now on? Or is that a waste of money? Thank you for your comments; your ideas are appreciated.

You would be correct in thinking it a waste of money. Tranny fluid only needs to be changed every 30 to 40 thousand miles, closer to 30 if you live in a very warm area or do a lot of stop-and-go sitting in traffic. Obviously checking the fluid on a regular basis is a good idea, but changing it when it doesn't need to be is a waste of money.

It's not like an engine oil . So, I have about 25 K miles on my Brougham and it's still running factory fill up lol . I asked a few tranny shops and they all said it should be fine .It's shifting smoothly and no slippings at all :)

Yes, as others have said, go by tens of thousands in mileage, and not a yearly thing.

Too much, and you're actually asking for trouble, constantly in there changing things without the need.

I concur with the 30-40K, as do many trans rebuilders (Shane? Can you PLEASE comment?)

I believe a lot of it has to do with the depletion of the friction modifiers. Lose them and the fluid isn't doing what it should.

Fresh fluid also keeps up the viscosity, you don't want it broken down either, the line pressures can't be correct if the fluid is shot.

If towing, change much more often, if not, then keep to the 30 to 40K.

And don't forget the diff! 7500 miles if towing, 30K if not. And most people just plain don't.... Try to change it after a run down the highway and note that all the heat is from the gears meshing together with all the power of the engine.... My T/A repsonded well well with Amsoil 75W90 in there, felt freer from 60+ mph up.... I prefer it....

And don't forget the diff! 7500 miles if towing, 30K if not. And most people just plain don't.... Try to change it after a run down the highway and note that all the heat is from the gears meshing together with all the power of the engine.... My T/A repsonded well well with Amsoil 75W90 in there, felt freer from 60+ mph up.... I prefer it....

A GREAT reminder for something I have to do myself. I highly doubt it's ever even been touched on my 12 year old, 128k mile car, but will soon, along with a new seal.