'02 Impala 3.4: Tranny Fluid Change

[Colt Hero]

'02 Impala 3.4l base model, 80k miles.

Tomorrow I'll be dropping the pan and replacing the fluid (about 7.5 Qts) using Dexron III/Mercon for the first time since I bought the car new. However, when I did this on my '97 Taurus GL 2.5 years ago (3.0, had 97k on it at the time - also the first fluid change), the shop manual specified a procedure whereby ALL the fluid was replaced. I used this procedure and it worked perfectly. It said to disconnect the tranny cooler line and run the car until the fluid stopped (~60 secs to drain 2-3 Qts), then overfill the system with 10 Qts and re-run on idle for 2-3 mins to drain out 10 Qts, then top up with 2-3 Qts. The Chevy's shop manual does not specify this procedure. It just says to pull down the pan and replace what's in there (~7.5 Qts).

Is the Ford procedure one that can be used on any car, or could it damage some transmissions? I'd like to use this procedure on the Chevy.

Also, the Taurus had a very nice rigid (reusable) pan gasket that spared me the agony of using the kit's cork gasket. I'm not sure if the Chevy has the reusuable gasket. If it doesn't, and I have to use the cork one, any pointers on installation? Right now I've got the gasket underneath some thick newspaper with my toolbox on top of it to straighten it out. Don't know why they throw that gasket into the box like they do (all curled up and twisted).

And yes, I'll be changing the filter (and O-ring) too...

[maxwedge]

I think you will find the gasket is the reusable steel reinforced type. Changing the fluid by running fluid thru it is a good way to get the tc flushed, can be messy though catching the purged fluid, make sure you identify which cooler to disconnect for catching oil purposes.

[richtazz]

I believe you can do damage to the pump if you run it too low, so I'd just change the filter and the fluid you lose when you drop the pan.

[maxwedge]

Originally Posted by richtazz

I believe you can do damage to the pump if you run it too low, so I'd just change the filter and the fluid you lose when you drop the pan.

Right there Rich, if you purge all the fluid and keep running that could happen, I shut it off soon as I see the end of the flow.

[Colt Hero]

Finally changed the fluid this weekend. Only pulled the pan and replaced what was in there (7.5 Qts). Turned out the gasket WAS the rigid, reusable type ... which was great. A few observations/issues:

1.) When I wiped out the pan, there was a residual dust-like greasy film that smeared up a bit as I wiped it. It all wiped off, but I wondered if this was a bad thing.

2.) The magnet had very little (if any) shavings on it. That was definitely a good thing.

3.) I made the mistake of insisting on replacing the circular filter seal. I've never seen a seal refuse to come out like that one. On my Taurus, it came out easily with a socket extension. I ended up buying a seal remover tool (double-dagger style), in order to get it out of there. The tool ended up scoring the cylindrical wall that houses the seal pretty good. Did I misuse the tool? I shined a flashlight into the hole to make sure I was grabbing the seal, but the dagger must've cut right through the seal and hit the wall behind it. Does this happen routinely? I tapped the new seal into place without incident and it covers the scoring so everything should be OK, but in the future, if the old seal looks OK, should I just leave it in there, or should you always replace the seal (because it could leak?)...

[tractorboy]

The seal is easy to remove. I have never removed the one on my impala. If it is anything like the one on my Celebrity, you just catch an edge with a chisel or screw driver and bend it in to wards the middle of the seal. This removes the the seals crip pushing all the way around. It then almost drops out. I would not run the pump dry. Thats the way a tire dealer here does oil changes. They take off the high tension lead or disable the car from starting, then remove the oil filter and crank the engine. The pump in the tranny i think has vanes or removable fins, it probably would not hurt the pump, i still would not do it. Maybe that is what is wrong with the 2 Taurus company cars we have. They both get this bucking thing going in the transmision. They are both from different years and were bought used 3 years appart. I just figured they were Fords.

[troy1]

I never replace that seal. Like tractorboy said just collapse the seal and it will come out easily. I would never let the flow stop.. run 2 qts out shut car off add 2qts run 2 qts out shut car off add 2qts. If your good you can just keep going adding fluid as it runs out into a pre measure container so you know where your at.