Changing Transmission Fluid and Filter - PeachParts Mercedes-Benz Forum

1981Benz · #1 09-06-2012, 02:02 PM

Hello All

,

I have a 1981 300SD turbo diesel and have enjoyed driving/fixing her for 5 years now. Now I want to change the transmission fluid and filter. I have the filter but am not sure how many quarts of ATF are required.

Any tips on draining/flushing the ATF would be greatly appreciated

Also, how does one reliably check the transmission fluid level?

Thanks,

NicK

Biodiesel300TD · #2 09-06-2012, 02:32 PM

If you can have the time open the drain plug and let it drain and drip over night. The valve body sits in the fluid and if you drain the fluid then immidiately remove the pan you'll end up with ATF dripping everywhere. It's a little cleaner opperation if you can let it drip for a while. Also make sure you meticulously clean out the allen bolts on the pan so the allen socket will go all the way into the bolt and help prevent stripping.

ROLLGUY · #3 09-06-2012, 02:40 PM

There is also a drain plug in the torque converter.

engatwork · #4 09-06-2012, 03:28 PM

Turn the engine over by hand until you see the drain plug in the torque converter and make sure you drain it too. Do you have a lift. Job is alot easier on a lift. Anyway, drain the pan and torque converter. Blow all the dirt from around the sealing edge of the pan to the tranny and drop the pan. Replace the filter (more fluid will drain out when you remove the filter) reinstall the pan with a new gasket, reinstall the drain plugs and add 4 qts to the transmission. Crank the car and add two more quarts. Start measuring and continue to add fluid to correct level. Be thankful you have a dipstick

.

toomany MBZ · #5 09-06-2012, 03:28 PM

Yes, be sure to drain the torque convertor.

You don't have to remove the axle cross member, you'll have more of a mess tho.

I'll suggest a new gasket, follow the torque vales, precisely.

DieselPaul · #6 09-06-2012, 05:58 PM

As stated if you drain the converter you're looking at around 6 quarts.

I buy ATF in the one gallon jugs, I get two jugs so I have an extra quart or two in the end to keep on the shelf.

1981Benz · #7 09-06-2012, 09:28 PM

Thats great there is a drain plug on the converter. My neighbourhood mechanic has a lift & I will share this information with him. Thanks for the help all, 453K km's, shooting for a MILLION

NicK

sixto · #8 09-07-2012, 12:09 AM

I had the benefit of owning for 3 months an '87 300D with a transmission fluid temperature gauge. It takes about 20 miles of driving to get the transmission fluid to a steady operating temperature of about 180*F. It's at that temperature that the dipstick reading is accurate. There's a guidance spec of 8-10mm below the min level for cold fluid. You'll overfill it if you set cold fluid within the MIN and MAX lines.

Sixto
87 300D

1981Benz · #9 09-07-2012, 04:06 PM

Thanks for the tip, next time I drive to town I will take a look at the dipstick. The tranny fluid is a pinkish colour with no burnt smell to it. I enjoy maintenance because you learn about the car and keep it in top shape for dependability. My 1994 diesel 6.5 GMC truck has WAY more issues and problems than my 1981 Benz. I wish Mercedes-Benz made a truck!

NicK

engatwork · #10 09-07-2012, 04:47 PM

They do

.

A.S. just purchased one:

Unimog

sixto · #11 09-07-2012, 05:10 PM

The 2012 Sprinter Van. Built to Work Smarter.

Our '97 C2500 Suburban has been reliable.

Sixto
87 300D

rmmagow · #12 10-23-2012, 10:18 AM

Please correct me if I'm wrong. On my 85 W123 I will be able to drain the Torque converter prior to removing the transmission pan? Drain pan, drain TC then proceed with pan removal and filter change? Lot less mess if I don't need to remove pan prior to TC drain.
Thanks.

qwerty · #13 10-23-2012, 10:25 AM

Quote:

Originally Posted by rmmagow

Please correct me if I'm wrong. On my 85 W123 I will be able to drain the Torque converter prior to removing the transmission pan?

In theory, there is no reason why you could not do that. The two processes are completely independent of each other.

Quote:

Originally Posted by rmmagow

Lot less mess if I don't need to remove pan prior to TC drain.

How do you figure that?

rmmagow · #14 10-23-2012, 10:40 AM

Drip, drip, drip with pan off and 100% guaranteed to be dripping on me :-) I know it'll be a bit of a mess anyway, just trying to see what I can avoid.

vstech · #15 10-23-2012, 11:52 AM

Quote:

Originally Posted by 1981Benz

Thanks for the tip, next time I drive to town I will take a look at the dipstick. The tranny fluid is a pinkish colour with no burnt smell to it. I enjoy maintenance because you learn about the car and keep it in top shape for dependability. My 1994 diesel 6.5 GMC truck has WAY more issues and problems than my 1981 Benz. I wish Mercedes-Benz made a truck!

NicK

fluid should NOT be pink... should be a bright to dull red. pink means water or air is in the fluid...