ATF fluid

[Pegasus_Red]

Im going to be changing my ATF fluid in the Benz pretty soon (changed the gear oil in the VW before and it was a breeze, so this should be too... hopefully and I used Mobil synthetic gear oil and am pleased with it in the Ghia.) . I have no idea what to expect, it could be nice and pink, it could be black, it could have metal shavings in it. I was thinking of going with a good Mobil synthetic fluid but I wanted to see if you guys had any experiences with ATF and what not before I go drop money on some fluid.
Thanks

[Jess]

Aqua Teen Force Fluid?

You probably know this already but just be sure you run the right type of fluid.

[Byrd]

Used it, Liked it (i don't know if there was a significant improvement but ah well)........... not much more to it

[gangsta coupe]

With the car being as old as it is, I would just put normal atf back in it. However I don’t know what those transmissions are like as far as durability. I have seen some people change it then the tranny stop pulling or start slipping.

[Jess]

I have seen some people change it then the tranny stop pulling or start slipping.

I've heard of that happening a lot too. if it's good as-is, leave it. If not, do a complete FLUSH, not just a drain-n-fill. The tq converter is probably holding on to 1.5-2 quarts.

[Pegasus_Red]

I just thought about asking my friend from cali an he says redline synth atf or Dexron III, might try that synthetic stuff but I dont want it to eat the gears (older metals sometimes dont like the new technologies because of softer metals).

Jess, how hard is a flush? Is that special equipment status or a DIY and have you done it before. Thanks guys

[gangsta coupe]

The only way I have seen or done a flush is with a machine. Before draining or flushing you should pull the dip stick and look at the fluid. If it is dark, burnt smelling, and you see little flakes or speck in it, DO NOT flush. The fluid and transmission is fucked, but the transmission just has not figured out it should die yet. In these cases for reasons no one has figured out yet, if you flush a transmission in this condition it will fail right away. Real strange, but that is what seems to happen. If your tranny is in this condition just drive it while you save to have it rebuild. There is no way of telling when it will fail. It might be today, next week, or next year, but it is fucked.

[Pegasus_Red]

well, I will look into it but these cars are still pumping fine after 230k (mine might have 167k or so) but Im hoping Mercedes did a little better than that. If worst comes to worse then it will be swapped for a 4 on the tree(:rock: ) manual, but we will cross bridges when we come to that as it may be too expensive to pursue.

[Jess]

best way to do a flush is with a machine although it can be done with some hoses, some containers and a large amount of ATF.

[ANTIVNM]

DON'T use synthetic unless your factory owner's manual or transmission builder says to.

Synthetic is known to be "slipperier" and cause bands/clutches to slip. Synthetic ATF is a well known no-no amongst the domestic crowd.

Flush is a good idea, but don't take it to some jackleg mechanic with a machine that PUSHES the fluid through. The proper machine will have a reservoir and a bladder, and let the transmission pump do the work. You can accomplish the same thing with a big flat (read Rubbermaid) container, and a few gallons of ATF. You just disconnect the cooler lines and let the "out" line hang in the bucket, while you pour fresh tranny fluid in the fill tube while the car is running. Most shops charge at least $90 for a flush by the way.

And make sure that you use a knowledgable mechanic if you do choose to have a flush done for you. If they connect the machine wrong, then they can wind up pushing dirt/old clutch material back THROUGH the seals. Bad things happen when you do that.

Me personally, I just drain the fluid often and replace the 7 quarts that my transmission holds, knowing that there are about 5 more quarts of dirty fluid in there. It works for me, and my 80,000 mile, stalled, and 200+ drag pass transmission hasn't had a problem yet.

FWIW, I am kind of the unofficial Auto Transmission Moderator on my home forum. :)

[Crankee]

If you have never flushed the system, dont do it now. What happens is over time the worn parts are sealed from the old fluid. Flushing will just bring the problems to the surface. If there is any, thats why you hear people having problems after flushing. If it was me I would change filter and fluid anddrive it just the same.

[TylerW]

DON'T use synthetic unless your factory owner's manual or transmission builder says to.

Synthetic is known to be "slipperier" and cause bands/clutches to slip. Synthetic ATF is a well known no-no amongst the domestic crowd.

Flush is a good idea, but don't take it to some jackleg mechanic with a machine that PUSHES the fluid through. The proper machine will have a reservoir and a bladder, and let the transmission pump do the work. You can accomplish the same thing with a big flat (read Rubbermaid) container, and a few gallons of ATF. You just disconnect the cooler lines and let the "out" line hang in the bucket, while you pour fresh tranny fluid in the fill tube while the car is running. Most shops charge at least $90 for a flush by the way.

And make sure that you use a knowledgable mechanic if you do choose to have a flush done for you. If they connect the machine wrong, then they can wind up pushing dirt/old clutch material back THROUGH the seals. Bad things happen when you do that.

Me personally, I just drain the fluid often and replace the 7 quarts that my transmission holds, knowing that there are about 5 more quarts of dirty fluid in there. It works for me, and my 80,000 mile, stalled, and 200+ drag pass transmission hasn't had a problem yet.

FWIW, I am kind of the unofficial Auto Transmission Moderator on my home forum. :)

That's everything I would have said. On top of that, Dexron III tends to be a more modern fluid. I would not use it unless the factory specifically calls for it.

Personally, I am not a fan of synthetic. Regular ATF will do just fine if you change your fluid as often as you are supposed to. There isn't much of an advantage to be had from a synthetic trans fluid, and in some cases it can completely ruin a transmission that wasn't designed for it (auto transmissions, being hydraulic, are extremely picky about what fluid you put in it).

A lot of imports use ATF+3 or ATF+4. I have no clue what an older car such as yours would take. I would do extensive research and find a specific fluid recommended by the factory if I were you.

[Pegasus_Red]

Thank you guys, I wont flush but Ill grab some dexron III thats non synthetic.

[TylerW]

Thank you guys, I wont flush but Ill grab some dexron III thats non synthetic.

Just make sure the factory calls for it. Many make the mistake of dropping that in a car that, for instance, calls for ATF+3. Bye bye trans. I've seen it happen far too many times so take the extra precaution and check for the factory oil.