I was rushing to top up my oil in my 1985 300TD, in a poorly lit garage, and I accidentally added probably about a half a cup of transmission oil before I realized what it was.

I then proceeded to add about another half a pint of proper engine oil.

What do you think. How bad is it to have that small amount of tranny fluid in the engine?

Better I do an oil and filter change now? Im due for one in about 2 months (or perhaps 1000 miles.) could it wait you think?

Thanks

Your D will use it to help clean out any built up gunk

__________________
1985 300D 198K sold
1982 300D 202K
1989 300E 125K
1992 940T

"If you dont have time to do it safely, you dont have time to do it"

"The democracy will cease to exist when you take away from those who are willing to work and give to those who would not."

Don't worry about it.

__________________

"Buster" in the '95

Our all-Diesel family
1996 E300D (W210) . .338,000 miles Wife's car
2005 E320 CDI . . 113,000 miles My car
Santa Rosa population 176,762 (2022)
Total. . . . . . . . . . . . 627,762
"Oh lord won't you buy me a Mercedes Benz."
-- Janis Joplin, October 1, 1970

the engine holds 2 gallons... 1/2 of a CUP is NOTHING.

__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

I thought so. I wasnt too worried, but again, I would rather get a second opinion.

Thanks for washing away any doubt....I will drive on

I just changed the oil in my boat's gear box. It said I could use either ATF or SAE30 engine oil.

I don't think you have anything to worry about!

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Graham
85 300D,72 350SL, 98 E320, Outback 2.5

You're fine. Putting some ATF into the crankcase to clean the engine out is an old mechanic's trick, and I have done it many times with no problem.

__________________

'98 E300 DT
'87 190D 2.5 turbo RIP
'92 S500 Sold
'03 3.2TL-S A-Spec

I'll agree that it's not an issue. In fact, ATF is a VERY good detergent and will wash out a lot of gunk. We used to use it with cars with sticky hydraulic valve lifters to get the crap out of them and it often worked.

You may see more junk than normal with your next oil change.

Dan