So it is clear that there are many differing views on changing the Transmission fluid and filter on a vehicle that has not had regular maintenance. Some feel it is safe to go ahead and change it, some feel that the new fluid might loosen up debris and cause major problems.

Here is what I propose...

What if I were to drain the fluid, not flush it out, simply drain it. then change the filter. then put the old fluid back in (excluding of course any large debris or perhaps after a straining).

This way there would be no new detergent in the fluid and I could have a brand new filter.

 

It's your car, do whatever you feel is right

Personally, I have never had any issues by draining the pan and torque converter and refilling with recommended fluid on any of my vehicles.

 

But I'm sure you change the filter at regular intervals. there are several discussions on here about the risks of changing after not changing it for a long time. then again some are lucky and dont have any problems even if they have never changed it.

My concern is that I have a vehicle with over a 100k miles on it and I have no record of any service. I fear putting in new fluid can loosen up debris and cause some serious problems

 

Nope, haven't owned anything long enough to make regular changes (usually 30k mile intervals). Any vehicle I have owned has had over 100k miles on it, and who knows if it was ever serviced.

 

hogwash

change the fluid and filter

if your tranny has issues then they existed already

 

I understand how you feel torque, but if you read other threads you will see that many believe that this gunk is the glue holding the car together. yes my tranny might already have issues, but i dont want to aggravate or rush them along.

I simply want to know how ridiculous it sounds to reuse the tranny fluid to avoid adding too many detergents

 

i can tell you from experience,...if the fluid is brown and stinks like its burnt real bad, dont change it. just a waste of money and its gonna make the tranny worse. i agree, if its that bad you have issues of course. my bud has a used car lot and ive seen it first hand a few times. car runs fine, change fluid and it starts slipping. obviosley these were trannys ready to take a dump anyway. again though, this was really brownish fluid and has a burnt smell. i use type-f in all my g.m. automatics. i believe it to be the best fluid, with the most anti-foaming agents. been useing it for 20-25 years. b and m recommends type-f if not useing theyre trick shift fluid. jmo.

 

if you wish to believe the myth then don't touch it, seriously. If it's already slipping then it's too late.

Every single used car I've ever purchased I flush all the fluids including brake. I've been doing that probably longer than most here have been alive.

 

Like I said, it's your car, do whatever you feel is right...

 

Even though I do my own maint. when it came to my transmission I went to Quick Lube and had them put it on the machine that filters all the old fluid out and puts new fluid in and then they install a new filter. This is just what I do.

 

Watch this link
http://www.youtube.com/watch?v=LTJjqr0QbIk

 

haha part of the reason I like to do as much work myself as I can

 

Everyone should add an external filter like the oil filter with a magnet stuck on the bottom of the filter. The filter in the pan is OK but not nearly as good as a mobil one filter plumbed in-line along with a cooler.