loudandheard

So while doing the power steering pump, I took off the under belly pans and saw that I have a leak in front of the transmission. I'm thinking that the trans connector plug is causing the leak, but I was not smart enough to check the connector. What does every one think?

Here are a few pics:











Here were a few pics of my backyard/garage, not related to the pics above:

TemjinX2

I would check the transmission connector and the pan gasket for the transmission pan. Worst case, i think it might be the crankcase seal. I haven't heard of it happening on a c32, but i think its happened on a few c55's.

91RS

That looks like engine oil to me. I had my valve covers fixed, but I've still got a little bit of oil there too and it's been too long to still be residual.

loudandheard

I found a pic of some one's transmission connector leaking.

Do you think it looks familiar?

loudandheard

I've had the valve covers resealed about a year or two ago. I've inspected the valve covers and they seemed to be fine, but I have not been able to check the rear.

AMS Performance

Your rear main crankshaft seal is bad.... only way to replace it is to completely pull out the transmission and replace. If its not too bad and you can live with it try upgrading to a thicker oil, that may help alittle bit.

Ultimately when you replace it you might as well rebuild transmission while you are at it so you never have to go through all that labor again. Its one of those jobs where you should replace as many maintenance components as possible while its out b/c its a heck of a job to do.

hope that helps...

loudandheard

That definitely was not some thing I wanted to hear. I wonder if I could do it my self. Does any one have a diagram with pics and part numbers for the rear main crankshaft seal?

What other parts would you recommend doing while doing this job. What does rebuilding the transmission consist of?

twinttsvr4

i took the transmission out last week. rear wheel drive trans are usually pretty easy. this was among the easiest ive done. first determine if its transmission fluid or engine oil. i had a leak from the 2 vents below the torque converter, ended up being the front seal on the trans ( front oil pump seal. either way, engine or trans, the transmission has to come out. while its out you should look into a new
tcu sleeve
trans pan gasket
drain and fill trans and torque convert, yuu can clean out the conductor plate on the valve body and all the shift solenoids.
you might want to take a wander over to autohausaz.com to check on some parts pricing as they will probably have the cheapest oem short of having a friend in an mb parts department

loudandheard

Did you have access to a lift? Were there any special tools needed to drop the transmission. Did you use have access to a transmission dolly? Can you provide a brief write up of what you did, I would prefer a long write up, but I'll take what I can get right now.

60n5pt1

Are those pics upside down?
I know I've seen some oil seepage when I took down my under belly shield and I'm thinking they're coming from the oil pan.

loudandheard

Yes they are, I was laying down under the car when I took the pics. When looking at the pic you'll notice O2 sensors. Maybe that will give you some orientation when looking at the pic.

You'll also notice that the pan is a bit further back, I'm hoping it's just the connector socket.

AMS Performance

no you cannot do it yourself, you need a tranny jack amongst other things to do it. Based on the pictures, with zero oil before the tranny and oil leak starting right at the begging where tranny meets engine block... 9/10 that's rear main crank seal which (engine oil of course).

Normally tranny fluid will leak from the Transmission Plug seal which is much further back.

The seal itself is a very cheap part (like $20 or something) and then you need some liquid gasket to seal off the back plate itself too. Its all in the labor.

since you have a C43, the tranny will blow eventually anyways since they are so notoriously weak. Might as well upgrade the internals and tighten up the tolerances to make it shift much better and handle much more power. Consider it a blessing in disguise. I know it isn't what you want to hear, but its better to know what you are dealing with up front instead of trying to fix it.

It may not be a bad time to consider selling the car and upgrading, your money will be much better spent in that regard than trying to spend $2k+ on a car that's barely worth $8k (just being direct).

hope that helps

loudandheard

I have a C32 if that makes a difference. The picture of the car in my avatar was my old 96 c220. If you look at the pics above you will see pics of my car. As long as I have a good guide, I don't think it should be that difficult. I know it's a lot of work, but any thing can be done. I definitely would be looking to upgrade a few parts while I'm in there.

I think my C32 with 135k on it is probably only worth around 10k-12k, but it's my daily and I love it. If I can do some maintenance and improve on importance, I don't see why not.

91RS

It's cheaper than buying a new one! That being said, I will say pulling a transmission is NEVER something I'd attempt in the driveway. I replaced the seal in my old 91 Camaro which is a much simplier car and I did it at work with all the proper tools (and a lift) and it was still aggrivating (and I didn't even have to remove the exhaust on that car).

loudandheard

I would definitely like to use a lift, but when it comes down to it I'll have to come up with a way to probably do it without one. Ingenuity comes out of necessity and nothing is impossible unless you give up. Should be a great learning experience, but well see what I decide to do.

chris.bachman

Let me know if you need some extra hands, I'll head your way.

loudandheard

When I decide to do it, I will definitely let you know. This job will certainly require a whole bunch of hands.

twinttsvr4

1.) ive done engine and tranny pulls without a lift about a dozen times, many of which on awd cars so i wouldnt say he cant do it himself. will it be a challenge, hell yes. its a PITA if you dont have the proper tools. i have a lift, transmission jack, 3rd man jack, air tools, and full array of tools including some very good swivel sockets to make the job easier

2.) while transmission fluid will leak from the electrical seal, it can leak from other places as well. all seals go bad.

3.) he has a c32 which is a 722.6 trans and fairly strong in terms of 5 spd autos. what i do notice in the pics is none of the o2 connections have any fluid on them and since i would expect oil from the rear main seal to be leaking right there i would expect these to be wet. i would jack the car up climb under and get some better pictures...probably in better orientation as well, not upside down

4.) no matter what the transmission is going to have to come out. like i said earlier. with it out youre just going to want to inspect everything you can. if you havent done the tcu sleeve now is a good time. also i good time for a trans drain and fill with a new filter. but as i also said before, verify what is leaking and where its coming from. check the oil level. has your low oil light been coming on because if your rear main seal is leaking it will trip the sensor. if you can get a universal dip stick you can manually check both the engine and trans however. there are threads for both on here. your leaking a fluid so logic would dictate something is low.

5.) As for a write up on everything i did to pull the trans, off the top of my head, R/R plastic drip covers, o2's, exhaust and all brackets, heat sheilds, brakets, trans mount, driveshaft, gebo(trans plate), trans bolts, torque converter, dropped trans...will transmissions out...split housing, pulled front pump seal, pulled front pump, inspected clutch packs and steels, reassembled, installed new pump and torque converter, and did everything i just said in reverse. i had already done new conductor plate, sleeve, filter and fluid the week before so none of that was neccessary while it was out.

loudandheard

When I first got the car a few years back my oil level would get low right before I would get my oil change. Since I've been doing my oil change I've noticed that I do not get the low level warning any more.

So I'm hoping it's not the engine, but either way I'm going to see what is going to be the best option. I do have a lot of tools at my disposal and I will purchase what ever is necessary before I even attempt the job.

Thanks for the help by the way.

loudandheard

Looks like the people said that my rear main seal was leaking was right. Arod Mercedes Benz was offering a free inspection of my car and I went in. Apparently they said it was the rear main seal and my rear differential is leaking from the pinion seal.

Does anybody know any thing about differential leaks. I need to replace the pinion seal, which I think is at the front of the differential where it connects to the drive shaft?

Phil C55

The car has 135k miles, it isn't pouring out and leaving a puddle on the ground. Judgement call on if it's worth all that work. Remember, if oil's leaking out, dirt isn't getting in. I changed a rear main on a 911 once and on start up oil poured out. When installing the seal, the spring popped off on the seal. The motor and transmission had to come right back out for a redo.

loudandheard

Damn, you have to be kidding me, I would hate for that to happen. The oil leak is minimum, it doesn't even drip oil, but it's bound to start sooner or later. I just don't like the idea of leaving it the way it is. I do plan on doing the work myself and I'll definitely go in knowing what I'm doing.

I think the first thing I'm going to tackle is the rear differential, I just wish I could get a quaife for a reasonable price. I was thinking that I should do Eurocharged torque converter while I had the transmission out, but those two parts cost more than what mercedes charges to do the actual fixes.

SteveoAMG

i looked underneath my car before i took it off andrew im gonna need to replace the rear main seal as well eventually and drop the tranny.. my brother knows more about this he was explaining how the procedure of what hes going to do...its a serious labor issue when using 9 quarts of oil when we really should use about 8 ... and it can be done just with a decent number of hands

loudandheard

I was looking over WIS on how to do the job and they recommend a special tool to install the rear main seal and that part costs $400+, just for the tool. You also have to take off the rear housing and they recommend that you replace all the bolts while you're at it.

This job looks like a pain in the ***, but I don't think it's impossible. What is turning me off to this job is the specialty tool that costs over $400, just for a damn tool. the

I found the seals for the rear differential, but I'm just not too sure how the job is done. Since my leak is coming from the pinion seal, the area where the differential connects to the driveshaft, I think I need a special tool to take out the seal. I am going to tackle this job first, should be pretty inexpensive if I can figure out how to do it. I think I may replace all seals while I'm at it, but not sure.

Sephiroth

I have the same rear main seal leak that you described. it's been 2 years since i've known about it... who knows how long it's been since it started leaking. Like some have said it's not worth the money to replace a $20 part. If it's not dripping just add some oil every time it gets low.

the diff is kind of a ***** since there isn't much oil to leak and it's not that easy to just top it off. hopefully you can figure out how to fix that yourself. good luck