Transmission fluid change


So I opt for a $90 auto transmission fluid change along with an engine oil change on my 2002 Trailblazer at the local oil emporium. I know they won’t be dropping the pan and replacing the filter, but I understood they suction out the old fluid. After the change I notice the bill says they put in 3 quarts of ATF. My manual says it takes 5.5 quarts and 11 including the torque converter. Is there any point/benefit at all to what they did?


Not really. Think of it like this. Drain out only a third of the crankcase oil. Now top off the level with fresh oil. All you did was contaminate the fresh oil with the dirty oil still in the pan.

Same works for tranny’s.



Must have been an Iffy Lube.

If they did a proper flush & fill, it would have taken much more than that. I suspect what they did was suck what they could out of the pan through the dipstick/fill tube, and refill the pan. You didn’t get what you paid for.


A little short lived benefit. You have half dirty and half clean ATF. For $90 they should have taken all the old ATF out. Go back and complain. Better yet, let us know where you went so we don’t go there.
My bros friend who worked at a dealer said they would drain half the oil, plug it up, put half new oil, oil change done.
This is why I do my own oil change.


It does sound like the botched the job. They should have got something close to at least the 5.5. Frankly I would have opted to have the pan dropped and filter replaced. I am not a real fan of flushing, but that seems to to open to a lot of friendly debate.

In any case you did get some benefit. The fluid is now about equal to what is a third of it’s life ago, so if it is now about 50,000 miles it is about equal to what it was like at 33,000 miles (if they had dropped the pan it would be more like it was at 25,000 miles). That’s better than were you were. Of course if you do this every 10,000 miles you should keep things in good shape, except for the filter.