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Discussion Starter #1
Hello.

My car has the infamous front crankshaft seal leak. Not wanting to drop tons of money on it at this point, I'd much rather keep the transmission topped off. It's gotten to the point where the fluid level is affecting the shift quality, so it would be best if I went ahead and got some of the fluid now. Checking with the dipstick shows that it is indeed a little low. I read that these transmissions are extremely sensitive to fluid level, and since it's leaking bit by bit, my car's poor shifting makes sense.

Anyone know where I can get a decent price on a bottle or two?

Thanks!
 

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1989 190e 2.6 1993 500sel (sold) 1995 S500 coupe (sold) 1994 S500 blk/blk
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I don't understand what a leaking crankshaft seal has to do with transmission fluid.

Just go to Walmart into the automotive section and buy the cheapest transmission fluid that you see, probably TECH.
 

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Discussion Starter #4 (Edited)
You're a funny one.

There is a correlation between the leaking that is happening and the transmission fluid's level. I was under the impression that perhaps the ATF was leaking from the seal. I see ATF that drips onto the transmission case (in between two bolts at the front) and then obviously hits the ground... so maybe the idea of the crankshaft leak was incorrect to begin with.
 

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'01-E320 & 02-ST2
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Maximos, it sounds like you haven't even done a proper inspection to determine where the leak is coming from. These transmissions are NOTORIOUS for a leak from a cheap little adapter/connector on the front right of the transmission, even at the dealer the part is like $15 and takes 45 minutes to change, from the time you get out the jack until you're finished washing up. As an added benefit, if you ignore it long enough fluid can travel up the harness and short out the TCM, which is many hundreds of dollars just to buy.

So why not do a little investigating before you resign yourself to adding $15/L fluid until the thing dies?

And you can't get too upset with the good Dr. After all, this is a site largely populated by MB (and other vehicle) enthusiasts, and enthusiasts tend to give short shrift to those who ignore a car problem by looking at a symptomatic response instead of fixing the problem. Or who may confuse key engine parts -- like a crankshaft -- with a transmission. FWIW, you could remove the crankshaft from every car on the road and never see one drop of transmission fluid.

Take care and enjoy the ride,
Greg
 

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1989 190e 2.6 1993 500sel (sold) 1995 S500 coupe (sold) 1994 S500 blk/blk
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You're a funny one.

There is a correlation between the leaking that is happening and the transmission fluid's level. I was under the impression that perhaps the ATF was leaking from the seal. I see ATF that drips onto the transmission case (in between two bolts at the front) and then obviously hits the ground... so maybe the idea of the crankshaft leak was incorrect to begin with.
I understand what you are saying now that you have explained it. I didn't mean to be frivolous or disrespectful. I just didn't understand how your topic sentence related to the rest of your commentary.
Good luck in solving your problem.
 

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Discussion Starter #7 (Edited)
My apologies.

Gregs, I checked out that adapter and it was completely dry...

So then then the fluid couldn't be leaking from the front main seal?

Where does the engine interface with the transmission?
 

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My apologies.

Gregs, I checked out that adapter and it was completely dry...

So then then the fluid couldn't be leaking from the front main seal?

Where does the engine interface with the transmission?
Seems like the earlier 5-speeds are more likely to leak from the O-ring on the pump than the front main. So you're seeing fluid coming down from the little inspection hole between the front transmission housing and the engine? So long as it's ATF and not engine oil that's a decent bet then.

Too bad it's not the adapter. :)

If you want to see how things break down go sign up for the EPC at EPC-net Online it's free if you're in the US. Then you can select your car and parse the menus until you see the major categories. Kind of fun really to look at all the various parts.

Take care and enjoy the ride,
Greg
 

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Discussion Starter #10
For some odd reason, "front crankshaft seal" and "front main seal" were synonymous terms in mind!

I assume that it isn't going to get worse if I just keep adding fluid? I think this would require dropping the trans to fix...

and Oliver -- thanks!
 

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Theres nothing like fresh auto trans oil, new filter, new gaskets,sometimes leaks can be caused by an old gasket, loose pan bots, dont forget to check auto fluid mark as per owners manual, dont think the worst, it might not be as bad as you think.
Cheers EJ
 

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Like I said, start afresh, clean and recheck, did YOU check the auto trans fluid level as per owner manual, after the job was done, or since, have you checked all hex key bolts, and gaskets, start simple, work toward the unthinkable.
Cheers EJ
 

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can some one post a pic of this adapter/connector or tell me exactly where it is and how it looks like? how does the fluid travel up to damage the computer? also, where is the trans computer? thanks
 

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can some one post a pic of this adapter/connector or tell me exactly where it is and how it looks like? how does the fluid travel up to damage the computer? also, where is the trans computer? thanks
If you check the stickies in the 210 forum you'll find most of that info, same transmission.

Take care and enjoy the ride,
Greg
 

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WTF? lol

Maximos, you are going about this the wrong way my friend.
If it's leaking transmission fulid, take it to an independent tranny shop or the shop that replaced the tranny. First find out what it is and how much it costs instead of guessing the worst. Most places will look at it for free.
If you're in Los Angeles, shot me an email. I can recommend a tranny shop or mechanic. My advice and factory recommendation is to only use MB tranny fluid.
 

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Discussion Starter #17 (Edited)
I've ordered 4L of MB fluid.

There are absolutely no good shops whatsoever in my immediate area.

I checked the fluid level at close to operating temp and it's actually at less than half (it was perhaps a two-mile journey in all... maybe it didn't expand enough?). I don't know if it's safe to drive the car like this, or what? I've stopped driving it for now, I don't want to dump $3k on a rebuild...

I just went out and measured it cold. It shows well within the 80 range. The other day, it showed above the 25 range (engine at 80). I thought that there was supposed to be hardly any fluid on the stick when it is cold...?

This is rather confusing.
 

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Is there something I am missing here? ATF doesnt leak out the front unless you have a power steering leak or a trans cooler leak.
 

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I've ordered 4L of MB fluid.

There are absolutely no good shops whatsoever in my immediate area.

I checked the fluid level at close to operating temp and it's actually at less than half (it was perhaps a two-mile journey in all... maybe it didn't expand enough?). I don't know if it's safe to drive the car like this, or what? I've stopped driving it for now, I don't want to dump $3k on a rebuild...

I just went out and measured it cold. It shows well within the 80 range. The other day, it showed above the 25 range (engine at 80). I thought that there was supposed to be hardly any fluid on the stick when it is cold...?

This is rather confusing.
Sounds like bad readings. You just have to keep doing until you're comfortable that you're getting good readings.
Actually, I think the readings are fine, it's more the reader. :rolleyes:

Maximos, with all due respect you need to learn more about the things you're trying to undertake.

This is not a Ford that you can "sort of" get right.

Fluid level in the 722.6xx transmission is very, very important. That's why there are two disparate marks on the dipstick.

The 25c range is used only for a cold fill after a drain or rebuild. Start the car, level ground, in gear, parking brake on, level should be in the range delimited by the 25c marks.

However that is the ONLY time you rely on the 25c marks. Once you have done this initial set, you then take the car until the fluid is 80c because that is operating temperature and the temperature at which the FINAL LEVEL is set. Then when the fluid is at 80C you make sure the fluid is in between the high/low limits on the 80C range.

In other words, you NEVER look at the 25C marks once you have the initial level set.

Also, you will NEVER reach operating temperature in a two-mile drive. And if it's cold, why are you looking at the 80C range??? Dude, you're making this about 100 times more complicated than it is.

You will need to drive the car enough to get the transmission fluid to 80C. Use a probe, carsoft or IR thermometer to be sure you are measuring it at the proper temperature. If you aren't, then you are simply wasting your time and endangering the health of your transmission. (Read that last sentence again a couple of times, okay?)

If you're concerned about the level before you get it warm, then check it by the initial fill noted above. Once it is within the 25C marks then stop measuring it and drive it until the fluid is at 80C, then set the final level.

Yes, this is a bit of a pain. That's another reason to fix the problem instead of messing around with adding fluid, but if you're going to drive around with a fluid leak then set the level properly or you'll be paying for another transmission instead of a seal repair.

Take care and enjoy the ride,
Greg
 
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