Annoying tranny dipstick!!! - PeachParts Mercedes-Benz Forum

Maroon 300D · #1 05-02-2006, 11:32 AM

I'm having some issues reading my dipstick. When I check it and it's cold, it's about 2-3 inches over the max line. When I check it after driving a couple of miles it's similar. When I check it after driving about 12 miles, it's about 1 1/2 inches over. I am checking it with the engine idling, the dipstick completely seated, following all the instructions in my owner's manual and in the Haynes manual as well.

The thing is, I doubt it could really be that high. The tranny was rebuilt by the previous owner last July and I doubt the fluid has been touched since then. The car has driven about 10,000 miles since then. The only shifting issues I have ever experienced are clunkiness on the first two upshifts, and it occasionally takes a bit longer to go into fourth during the first ten minutes of driving on a cool morning. I have a vacuum leak which I suspect is the cause of the clunkiness; I will fix that this week.

The fluid on the dipstick is a little bubbly but in no way 'frothy.'

Any opinions? Could I be wrong and it really is that overfilled? I have the receipt from the rebuild and the tranny is under warranty for 12,000 miles or until July 25, whichever comes first, so if a flush is in order, or if damage has likely been done, they can take care of it!!

Thanks in advance.

janko · #2 05-02-2006, 11:50 AM

that clinton phrase, 'i feel your pain', fits here. i too have a dickens of a time checking the transmission fluid level. in my case i sometimes get a good reading on one side of the stick but not on the other. read here sometime back that perhaps taking some denatured alcohol to the stick would cure this. did not work for me. i really have not provided anything other than a 'bump'. will naturally follow the response set.

d.delano · #3 05-02-2006, 12:13 PM

You pretty much have to drive it 20 or so miles, and let it idle for around 5-10 minutes on level ground to get an accurate reading.
Draining while hot and refilling can answer the question for you, by comparing the volume of the fluid that was in it with the volume listed in the owner's manual while taking into account the trans cooler and lines, you can tell if you leaked any out or whatever. I hate checking the tranny fluid so much I just replace it every year and a half or so. Gives me something to do and peace of mind.

Maroon 300D · #4 05-02-2006, 12:59 PM

Well thanks for feeling my pain and for the advice. I'll try the 20 miles and the longer idle time, I guess, although my girlfriend thinks I'm being neurotic about this and I'm sure to hear comments when I go to check it yet again. She's right, of course.

Now if it really is way overfilled, or even a little overfilled, wouldn't someone (me or the PO) have noticed some sign of this? From what I've read, overfilling the tranny is very bad and will lead to excessive wear quickly. Could it be that everything might be working as well as it is even after 10K miles with overfilled tranny fluid? From what I've read the hard shifts are usually a vacuum issue and not a fluid issue.

Thanks!

janko · #5 05-02-2006, 01:10 PM

if you find that your fluid level is really too high, i offer this suggestion. visit a vet. yes, strange as it sounds, a 'dog doctor'. purchase a 'syringe'. afix a piece of plastic tubing to same. and suction out excess from dipstick orffice. historical postings suggest a 'turkey' baster. that be close to a diaster compared to vet device. the syringe that i use has a capacity of say 2 oz. couple/three/four iterations may solve your problem. and get you back on track. nice thing about syringe - it works and does not leak/drip/etc. my last visit to vet to purchase item - around a dollar. good luck.

d.delano · #6 05-02-2006, 01:27 PM

Janko I did just that w/ my MityVac, and lo and behold the tranny started slipping due to insufficient fluid level. I only withdrew about a half quart. These trannys are sensitive to fluid level. So be careful if you do that.

janko · #7 05-02-2006, 01:35 PM

mr. d. i understand. my suggestion was a method to achieve proper fluid level. without a mess. nothing more.

d.delano · #8 05-02-2006, 05:55 PM

Hey I wasn't saying anything... It's just that I had the same idea and since the dipstick likes to play tricks on you, you need to be careful when taking fluid out, because it might be that you have the correct level in there to begin with.

janko · #9 05-02-2006, 06:04 PM

mr. d. you and i be copasetic. and good day to you , sir. i toast you in a minute or two. pray, you are not a teetoller! and hope also my spelling not be too bad. gby.

1983/300CD · #10 05-02-2006, 07:01 PM

Hot, Level, In Park & Running.

BTW, any auto supply store should sell fluid syringes.

Palangi · #11 05-02-2006, 10:13 PM

It is overfilled.

I find the easiest way to reduce the level is to just remove the transmission drain plug and let out about a quart.

Anybody care to guess what the transmission service manual actually says about the most accurate method of fluid level measurement?

slarson80 · #12 05-02-2006, 10:49 PM

After driving it and checking on level ground, I was still reading way high. Also, when going from park to drive or reverse. The tranny really clunked and it felt like I had to keep my foot pressed firmly on the brake while doing so. It never felt like that before. I made a pump from an old liquid hand soap dispenser. After thouroughly rinsing it I went to the hardware and got some plastic tubing that was the same diameter as the stem on the pump, they had it on a spool and a dipstick length was about $1.38. after purging some clean ATF (from a bottle) through it. I stuck it there and pumped out almost a full quart. Shifts much smoother now, both while driving and when putting it in gear. It reads almost full after I've driven, parked on level ground, then wipe and check a few times.

Keith_otr · #13 05-02-2006, 11:02 PM

I check mine about 15 times.....and take an average of the readings. Something funky goes on inside the tranny dip tube that messes with the readings.

dieselmania · #14 05-02-2006, 11:48 PM

Try this, drive it till hot, park on a level spot, shut it down. Come back in 15 mins, start it up, check it. It will still be hot and you'll be able to get an accurate reading since the fill tube will be drained by then. Been doing it this way on my 87, works great.

H-townbenzoboy · #15 05-03-2006, 12:05 AM

Here's the method I use.

First, get the fluid to operating temperature by taking a 20 mile freeway drive. Then, park it on level ground, and remove the dipstick. Shift the car through each gear, and leave it in each gear for a second with your foot on the brake, when you get back to park, let it idle for about 3 minutes. Wipe the fluid off the dipstick with a lint free rag, and reinsert it. Pull it back out after 4 seconds and check the fluid level. If it is low, slowly bring it back to the right level, the distance between the MIN and MAX marks on the stick is 0.3 liters. I just had the same problem as you, turns out I was overfilled by a quart, took care of that with my Liquivac though.