Best Way To Change Auto Trans Fluid on a 94 SL2

[Fricken eh!]

Hello,

I am looking to change my transmission fluid. I have seen these "power flushes" that the local "sheisters", aka auto transmission repair shops, offer for about $100 that suck all the old fluid out. This seems like a good idea, but not at that price! Can I disconnect the transmisoon cooler tube from the radiator and drain that into something with the car running in D? Can I drain out all the fluid and then shut the car off to fill w/o damaging anything?

If not, what is the best way to change it? Will using the drain plug and changing the filter be enough to flush out the old fluid?

Thanks!

[Luke]

It has worked for me......simply regularly changing....

[eljefino]

You are fortunate to have a drain plug and easily reachable/changeable filter. Most other cars don't and have a pan that makes a royal mess when dropped and needs resealing every time. The cooler flush people invented this gadget for those cars.

Luke is right; service it the way saturn intended. Doing it a few times in quick succession (fluid is cheap) will essentially dilute the original fluid to nil. This is overkill... but a good kind.

[trock859]

I've read on here that the trans holds about 7 quarts of fluid, and you usually change about 5 quarts when draining the fluid and replacing the filter. So you leave about 28% of the original fluid.

If you changed it again, you would then have approx 8% original.
A 3rd time would leave about 2% of the original fluid.

Unless there was a reason for great concern about the fluid, I would change it like normal and wouldn't worry about it until the next 30k miles go by.

[Luke]

Fm Trock
Unless there was a reason for great concern about the fluid, I would change it like normal and wouldn't worry about it until the next 30k miles go by.

Works perfectly for me; And I don't even wait for the 30,000 miles.

[wolfman]

The "S" series transaxle was designed NOT to require "flushing" Hence the external filter, magnet(s) etc... DO NOT pay for this "service" a drain, filter change and refill (at the scheduled intervals in the maintenacne schedule) are all that is needed or required.

[Bill Murray]

Luke & Wolf have it spot on as usual.
I recommend the factory filter as it takes a lot more pressure than an engine one and some of the aftermarkets aren't as stout in the can thickness.

[Fricken eh!]

ok this topic seems less controversial than my brake bleeding one. thanks for the replies. i will do it the easy way.

thanks!

[Lucas1]

Originally posted by trock859
I've read on here that the trans holds about 7 quarts of fluid, and you usually change about 5 quarts when draining the fluid and replacing the filter. So you leave about 28% of the original fluid.

If you changed it again, you would then have approx 8% original.
A 3rd time would leave about 2% of the original fluid.

Unless there was a reason for great concern about the fluid, I would change it like normal and wouldn't worry about it until the next 30k miles go by.

it holds 4.0 quarts drain/fill, 4.25 quarts with drain, fill and filter(external). they do hold more than that, but if you change your fluid every 30K like you should then there is no need to try to get every drop out. its nothing to stress about. all of the percentages dont really mean anything since theres no way to tell what percentage of the fluid your draining is new or old.

BOTTOM LINE: change the fluid and filter every 30K, or less. then you have nothing to worry about.

[Tiger]

Originally posted by Fricken eh!
Hello,

If not, what is the best way to change it? Will using the drain plug and changing the filter be enough to flush out the old fluid?

Thanks!

I just drained my fluid last night and put in Mobil 1 Dex lll. Seems to be shifting very smooth....Don't do what I did on the refill. I used one of those expensive gadgets that screws onto the bottle, has a valve, and a long clear hose. Thought this would work better than a funnel. I was wrong! Trans fluid sprayed onto the coil pack out of the filler tube. An hour or so latter, my coil pack was very clean, and I had cleaned up the mess. Also, according to what I read in Alldata, the ideal fill level is just above the hatch marks. Drained 4 quarts and put in 4 quarts, but it is at or above the hot full mark. I think I should have just added 3.5 quarts then checked the dipstick...Oh, the joy of DIY! After I was done, I found a nice blue funnel with a long neck and angled. Would have worked perfectly! Maybe I was just meant to clean that coil pack?

I am also into overkill. Since my car was a little abused and late on maintenance, I am changing fluid early. I read something by ssicarman about doing several quick fluid changes to get more of the old fluid out of the system. That is for a neglected system, and you would only change the filter one time. But, if you or the previous owner was good on maintenance, changing the fluid and filter at least every 30,000 is recommended.

[Tiger]

Yep, just read owners manual and Alldata again. Looks like I have a little too much fluid in there (above hot full mark). Oh well, I bought some plastic hose to suck some out of the filler tube. Alldata has a nifty picture of a dipstick. Says the ideal operating range when hot is right at the top of the cross hatched area. Think I will shoot for that this time. Good luck!

[Tiger]

Oh, I did not need to add as much fluid as you will. This time I did not change the filter, just drained fluid and filled. Not due for the filter yet. You will probably need to add more fluid to get it to the appropriate level.

[Luke]

Fm Bill
Luke & Wolf have it spot on as usual.

Wolf has it spot on, as usual....I still need to remember simply to take my brain pills. Wolf is in his own league.........

Fm Tiger
I think I should have just added 3.5 quarts then checked the dipstick..

This is exactly what I do....the approach works perfectly...