I've looked this up but most posts are from long ago and don't have the modern ATF that you can find in most stores.

What recent ATF have people had success with?

I just use regular Valvoline Dex III. in my '84 300D.

__________________
"The MB W123 is so bulletproof, you can drive them forever. Which is a good thing as it takes that long to get anywhere."
Betsie: 1984 W123 300D (hobby, 280k miles)
Myrla: 2001 Mazda Protege 2.0 ES 5spd (daily driver, 130k miles)
The Turd: 2007 Toyota Camry (wife's car, 118k miles)

Dex/Merc is the current ATF for transmissions that used Dex III. Use that. Valvoline is a fine choice, though not the only one.

__________________
1979 300D 040 Black on Black - 1985 300D Maaco job (sadly sprayed over 199 Black Pearl Metallic) on Palamino

http://i.imgur.com/LslW733.jpg

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Dex III is the right stuff. Most big box stores (wally world, etc) as well as most parts houses have it. Make sure the clerk understands Dex 3, not Dex 4. Dexron III is also marketed as Mercon III.

I just use standard Dexron/Mercon "Dex/Merc" (which is DexIII) in all my older Benz transmissions.

Most bottles don't call it Dex3 anymore because the new GM standard is fully synthetic dex6.

__________________
68 280SL - 70 280SL - 70 300SEL 3.5 - 72 350SL - 72 280SEL 4.5 - 72 220 - 72 220D - 73 450SL - 84 230GE - 87 200TD - 90 190E 2.0 - 03 G500

Nissan GTR - Nissan Skyline GTS25T - Toyota GTFour - Rover Mini - Toyota Land Cruiser HJ60 - Cadillac Eldorado - BMW E30 - BMW 135i

I've been using Mobil 1 for more years and miles than I care to remember. It may be a bit of overkill for these cars but I've never had a problem. I change fluid every three years as well.

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1977 240D
1981 300SD

OK what about this stuff?

http://www.walmart.com/ip/Valvoline-MaxLife-Dexron-Mercon-Automatic-Transmission-Fluid-1-Gallon/15125768

Might want to actually read on the side of the bottle..... to see if Dex lll is listed...

__________________
1980 240d ,

chain elongation, cam marks reference:
http://www.peachparts.com/shopforum/diesel-discussion/10414-help-i-need-check-stretch.html

http://www.peachparts.com/shopforum/diesel-discussion/305365-9-degrees-chain-stretch.html

evap fin cleaning:

http://www.peachparts.com/shopforum/diesel-discussion/156207-photo-step-step-post-showing-w123-evaporator-removal-1983-240d-1982-300td.html?highlight=evaporator

A/C thread

http://www.peachparts.com/shopforum/diesel-discussion/297462-c-recommendations-mb-vehicles.html

The Maxlife Dex/Merc is suggested for Dex 3 applications, and it worked great in my 85 190D automatic. Any Dex 3 ATF will be fine. If you stick to conventional Dex 3, do 3 year 30,000 mile changes when you change your diff oil and brake fluid and you won't have any issues.

__________________
'84 190D 2.2 5MT (Red/Palomino) Current car. Love it!
'85 190D 2.2 Auto *Cali* (Blue/Blue) *sold*
http://badges.fuelly.com/images/sig-us/302601.png
http://i959.photobucket.com/albums/a...0/sideview.png

OK one list thing. Let's assume I empty out all of the ATF even from the Torque Converter. What is the refill and check procedure on this? Check it while running, hot, and in park and should be between marks?

Yes, running, hot and inbetween the marks. Be extremely clean when working on the transmission, the slightest impurity can cause issues and clog a valve body. Wipe the dipstick with your fingers, not with a rag. To refill, buy a transmission funnel. They are only a couple of dollars, and come with a fine mesh filter, a tube and usually a stop on it, so you can fill (and measure) with the funnel. Fill through the dipstick tube.
On my 84 300D the tranny takes a hair over 6.5 quarts to fill it all the way up with tranny fully drained and dropping the pan to change the filter.

__________________
"The MB W123 is so bulletproof, you can drive them forever. Which is a good thing as it takes that long to get anywhere."
Betsie: 1984 W123 300D (hobby, 280k miles)
Myrla: 2001 Mazda Protege 2.0 ES 5spd (daily driver, 130k miles)
The Turd: 2007 Toyota Camry (wife's car, 118k miles)

A lot of fluid can be clinging to the insides... so creep up slowly on that full mark carefully... a lot easier than having to pull some out.....and overfilling can cause foaming... bad on several levels....

__________________
1980 240d ,

chain elongation, cam marks reference:
http://www.peachparts.com/shopforum/showthread.php?threadid=10414

http://www.peachparts.com/shopforum/diesel-discussion/305365-9-degrees-chain-stretch.html

evap fin cleaning:

http://www.peachparts.com/shopforum/diesel-discussion/156207-photo-step-step-post-showing-w123-evaporator-removal-1983-240d-1982-300td.html?highlight=evaporator

A/C thread

http://www.peachparts.com/shopforum/diesel-discussion/297462-c-recommendations-mb-vehicles.html

Also FYI if you try to dump 6.5 quarts in right away, it'll puke out of the vent and onto the ground. Fill in like 4 quarts, start it up for a few seconds, then fill in the rest.

FYI #2 the trans does not heat up at the same time as the engine. Just because your temp gauge says 90C doesn't mean the trans is that hot. You need to take it on a highway drive for about 30 minutes to get it properly heated up. At that point, on level ground in park engine idling the fluid should be between the marks on the dipstick. Like Leathermang said if you overfill it, it will foam up and destroy the transmission. If you can't heat it up all the way properly, you can measure the point below the hot marks on the dipstick, and check it dead cold. The measurement below the hit marks is in the FSM.

__________________
'84 190D 2.2 5MT (Red/Palomino) Current car. Love it!
'85 190D 2.2 Auto *Cali* (Blue/Blue) *sold*
http://badges.fuelly.com/images/sig-us/302601.png
http://i959.photobucket.com/albums/a...0/sideview.png

I filled my tranny with 6.5 quarts after a complete drain, and it never puked anything out. Hold it in every gear for a minute so it can build up pressure everywhere, and I don't think you'll have a problem.

__________________
"The MB W123 is so bulletproof, you can drive them forever. Which is a good thing as it takes that long to get anywhere."
Betsie: 1984 W123 300D (hobby, 280k miles)
Myrla: 2001 Mazda Protege 2.0 ES 5spd (daily driver, 130k miles)
The Turd: 2007 Toyota Camry (wife's car, 118k miles)

Best bet, as often preached by whunter, is to drain ATF and measure what you removed. Then refill with that exact amount.

It's important to note that when filling after a change, when everything is cool, the "Fill" mark on the dipstick is not accurate. The transmission can be full as much as 30mm below the "low" mark. Filling it up to the fill mark would lead to a very overfull transmission, in such a situation.

Generally speaking, when in doubt err on the side of being a bit low on fluid. This is more forgiving than being too full of fluid.

__________________
1979 300D 040 Black on Black - 1985 300D Maaco job (sadly sprayed over 199 Black Pearl Metallic) on Palamino

http://i.imgur.com/LslW733.jpg

The Baja Arizona Oil Burners Send a message if you'd like to join the fun
Left to Right - UberWasser, Iridium, Stuttgart-->Seattle,, mannys9130

Visit the W123 page on iFixit for over 70 helpful DIY guides!