According to owner's manual, ATF level should be at full/maximum mark when transmission is at operating temperature; OR 10mm (about 1/2") below minimum mark if at shop (i.e. room) temperature. So I check my level when cold and it's where it's supposed to be. But then I check when hot and it's 1/4" ABOVE full mark. And yes, I give it several minutes to settle down and cycle through R, D, and N.

I might have thought that 1/4" is nothing to be concerned about, but several much more knowlegeable than I have encouraged me to remove the excess.

What gives? Which of the two readings is likely to be more reliable?

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14 E250 Bluetec 4Matic "Sinclair", Palladium Silver on Black, 159k miles
06 E320 CDI "Rutherford", Black on Tan, 178k mi, Stage 1 tune, tuned TCU
91 300D "Otis", Smoke Silver on Tan, 145k mi, wastegate conversion, ALDA delete

19 Honda CR-V EX 75k mi
Fourteen other MB's owned and sold
1961 Very Tolerant Wife

Were you parked on level ground?

__________________
RRGrassi


70's Southern Pacific #5608 Fairmont A-4 MOW car

13 VW JSW 2.0 TDI 193K, Tuned with DPF and EGR Delete.

99 W210 E300 Turbo Diesel, chipped, DPF/Converter Delete. Still needs EGR Delete, 232K

90 Dodge D250 5.9 Cummins/5 speed. 400K

Gone and still missed...1982 w123 300D, 1991 w124 300D

Yes. And I've measured it a few different places.

__________________
14 E250 Bluetec 4Matic "Sinclair", Palladium Silver on Black, 159k miles
06 E320 CDI "Rutherford", Black on Tan, 178k mi, Stage 1 tune, tuned TCU
91 300D "Otis", Smoke Silver on Tan, 145k mi, wastegate conversion, ALDA delete

19 Honda CR-V EX 75k mi
Fourteen other MB's owned and sold
1961 Very Tolerant Wife

Forget about the room temperature location. All automatic transmissions should be at the full mark when hot (after a short drive) idling in Park on level ground.

Never check transmission fluid cold.

The only accurate reading is at operating temperature.




Have a great day.

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1983 300D
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Ok, well the issue just may be too much tranny fluid, if it exhibits the same thing, constantly. It is always best to check the tranny fluid when the the engine and tranny are hot, engine running. This is the only tim I would consider using a dipstick oil extractor.

Have you, or any one else added fluid or conditioners lately?

Cold method is only good for ballpark level after fluid/filter changed.

__________________
RRGrassi


70's Southern Pacific #5608 Fairmont A-4 MOW car

13 VW JSW 2.0 TDI 193K, Tuned with DPF and EGR Delete.

99 W210 E300 Turbo Diesel, chipped, DPF/Converter Delete. Still needs EGR Delete, 232K

90 Dodge D250 5.9 Cummins/5 speed. 400K

Gone and still missed...1982 w123 300D, 1991 w124 300D

It takes a lot more than a short drive to hit 80C.

He pretty much said it right there,lol. The big thing is that you don't want it to foam the oil, thats when you can damage parts, if it's not foaming, you're probably ok, but should look into getting a little of it out when time permits. You could probably loosen the banjo bolt on the bottom of the dipstick tube to let some out if you have that setup.

__________________
Chris
64 190D R.I.P.
80 240D W/617 engine -for sale
82 240D -for sale

not on my SD... 2 to 3 miles, and she is on the mark!
John

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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 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

Thanks for the feedback.

Clearly the only safe approach is to measure when hot. I wonder why the manual gives the cold option; curious, given the danger of overfilling.

__________________
14 E250 Bluetec 4Matic "Sinclair", Palladium Silver on Black, 159k miles
06 E320 CDI "Rutherford", Black on Tan, 178k mi, Stage 1 tune, tuned TCU
91 300D "Otis", Smoke Silver on Tan, 145k mi, wastegate conversion, ALDA delete

19 Honda CR-V EX 75k mi
Fourteen other MB's owned and sold
1961 Very Tolerant Wife

I've got one of those digital IR temp gages making it very easy to check fluid temp. I've used it on several cars. In my experience, it takes miles of driving on local roads to approach 80C. On my GM car, I've never been able to get it above 67 - 70C regardless of ambient temp or miles driven.

For sake of curiosity, I've checked my fluid at both the "cold" indication and the "hot" indication. I got FULL readings at both.