WallaceLau

Hello,

We have a 2002 C Coupe (2 door hatch) that has developed a transmission problem - within about 2-3 miles from our garage the transmission will either refuse to shift (usually stuck in 2nd gear) or shift into neutral and then refuse to shift into gear. Putting the car in park, wait a little, and it will shift again. Took it to a mechanic and was quoted $4000 for a complete transmission rebuild. But the car sounded normal... no funky noise or anything grinding from the transmission, shift smoothly, etc. Seems like a valve or electrical problem, so my question is, has anyone had similar issue before and does it really require a complete transmission rebuild? We love this little ride and it only has about 70,000 miles... but since blue-book value is only about ~$5000 I can't really justify spending 4 grand on a new transmission.

Any opinion will be greatly appreciated!!



Wallace

LILBENZ230

Check fluid level immediately. Report back.

Glyn M Ruck

+1^ And try and read stored codes with a transmission code capable OBDII scanner.

saespyder

Which parts of his post lead you to believe it's fluid level?

Dust2Dust

4k?

Seriously?

search junk yards you can probably find a transmision for under 2grand

Glyn M Ruck

The fact that it is going into limp mode.

About 80% of all auto transmission problems are fluid level related. On old hydraulic, vacuum, speed transmissions it was about 98%.

OP - please also check the electrohydraulic bush for leaks.

SeaCoupe

You guys think he could benefit from unplugging the TCU overnight and replugging it in?

You guys know I'm a fan of resets.

SunnyRayToronto

I'm wondering did you ever do a transmission oil change at 39,000mile (60,000km)?

Did your mechanic even hook up your car to Mercedes-Benz STAR Diagnostic System? It can run a number of tests and checks on various systems of your car including the transmission and pinpoint the source of the problem you're having. Take it to a good MB Indy.

Most OBD2 ScanTools including the Innova Equus 3130 that I have can not pick up most (if any at all) transmission codes. My OBD2 Innova Equus 3130 can not pick up the P2200 & P2203 codes that my car is storing, but of course Mercedes-Benz STAR Diagnostic Systems can.

As per Gly_M_Ruck, I'm betting you have a transmission oil leak at the pilot bushing adapters with bad o-rings (Mercedes part# 203-540-02-53),.... I'd be surprised if the transmission oil leak was anywhere else,... actually I'd be shocked!
See post #2 here:
https://mbworld.org/forums/c-class-w...sues-help.html

http://www.installuniversity.com/mb/...ans_oring.html

WallaceLau

Guys,

First of all thanks for all the input! Let me try to get the car back from her mechanic and maybe bring it to another shop... I do know my OBD-II tool just give me a generic read-out (check transmission or something like that) and I am guessing her mechanic may not have the STAR diag tool either.

For your information, this is my GF's car and it was bought new and maintained by the dealership + an indy shop. So all the fluid changes / oil changes should've been done on-time (and at their butt-r*ping price). In the contrary, I drive a Honda Pilot and do all the maintenance myself (oil change, trans/tranny fluid change, brake rotor, etc), so I am fairly confident I can work on the C230. However, I didn't really want to offer to maintain/fix her car... you know how that goes... even if I am saving her money and doing everything properly, if something goes wrong it would be my fault. So I just sent her to whatever shop she picks.

With that in mind, I doubt I want to mess with the transmission myself either, as she'd just blame me for making things worse. So the big question is, do you guys think we can save some money by bringing it to a dealership? For example, if a dealership can read the code and get it fixed by, say, just a fluid change + reset, that would be quite a bit cheaper than the $4000 rebuild. If I want to put it a different way, from your experience (and considering the symptom) is it safe to say the chance of actually needing a new tranny is small? If so, I will get the car moved...

Thanks!!



Wallace

Glyn M Ruck

You really need to read all the stored codes to make that decision with a Star or something like a Snap On Solus.

At the moment we are guessing. My early guesses would be Fluid Level, Electrohydraulic bush leak, conductor plate.

Read those codes.

sammydragon3

i'd get rid of that ugly thing...i'd rather have an ford geo then c230 coup

LILBENZ230

That's an emphatic NO. You'll never "save" money by going to a dealership even though sometimes it ends up being your only option.

The most important things to do:

1. Get codes read.
2. Check fluid level.
3. Check pilot bushing for leaks.

LILBENZ230

Your posts are exclusively worthless. Why do you keep chiming in?

SunnyRayToronto

WallaceLau,... please update your profile. What is your location? Which city are you in? Hmmmm, you joined in 8 years ago and you're only on your 3rd post,.... Wow, talk about stalkers!

Anyways, even if the car followed every single service and recommended fluid change,... here's the problem: Mercedes-Benz USA & Mercedes-Benz Canada says these transmission oil will last a lifetime and NEVER require any transmission oil change. Yet, everywhere else in the world Mercedes-Benz of that region recommends transmission oil change every 60,000km (39,000 mile). Scan through this forum and you'll see many threads relating to transmission problems. It doesn't take a rocket scientist to figure out why. These 722.6 transmissions are very robust and durable,... but they do need regular transmission oil changes and inspection for leaks mainly at that infamous pilot bushing.

Unless, this car has been badly and I mean really badly abused, I'd be shocked if this transmission really needs a rebuild at 70,000 miles.

For Transmission problems you should have Mercedes-Benz STAR Diagnostic System run through a bunch of tests and checks on the transmission system to pinpoint exactly what's wrong. It'll also come up with the suggested parts to replace or inspect further.

Fluid transmisson level you could check yourself,... oops,.. there's no transmission oil dipstick,... but you can make one! I would suggest using about 1.2 metres of 1/4" polyethelene tubing (usually cloudy white and stiff but flexible enough - unlike the clear tubing which are too flexible and will flex-out at the bottom of the pan giving you a false reading). The polyethelene tubing are commonly found in plumbing section of HomeDepot, Lowes and most hardware store for about $3. Get an infra-red temperature reader. The transmission fluid level should be read at 80 degree Celsius (with markings between 54 and 65mm from bottom of dipstick),... forget about the 25 degree reading on the dipstick, MB-Techs have been instructed to only do transmission oil level reading at 80 degree Celsius,.... and so should you.
https://mbworld.org/forums/c-class-w...-me-p0730.html

And it certainly doesn't sound like its time to get rid of the car,... do these routine check for transmission fluid level and leaks,.. and then get a proper diagnosis on Mercedes-Benz STAR Diagnostic System.

Anyways, the above is just my advice for the car,.... now for more personal advice, if you're intimidated by your GF bit-ching at you after you try to help her to the best of your abilities,.... then its probably time to get rid of her! Oh, and get rid of that mechanic while you`re at it too!

samaritrey

The car should be running as well for the fluid check right?

Glyn M Ruck

Running in PARK!

sammydragon3

it could be your valve body...if u know cars open up the valve body and manually check to see if the clutch packs engage

it wouldnt be ur conductor plate cause u'd be getting speed sensor codes

Glyn M Ruck

Sammy - both of your comments are nonsense

C230 Sport Coup

1st thing you need to do is determine if the TCU is soaked with oil wicked through the harness. That can by easily done, pull back passenger side carpet, as shown in the pics
Glyn referenced in the link he posted. If there is oil, there is your problem.

Then it's a matter of doing a flush and fill, replacing the orings, cleaning the oil out of the harness, and possibly purchasing a new TCU.
All of that will cost well under a grand, depending on if you are willing to do any of the work yourself.

Also mentioned was just checking the level. Purchase a 722.6 dipstick from Ebay or the dealer and check it.

How many miles??

1st thing's 1st Sammy. No point talking about transmission internals without checking the basics 1st.
And the 39K mile change is related to the 7 speed. Many 5 speed owners go 100K + before the fluid finally just gives out, like mine did at 120K. BTW- I have 183K and the original tranny is fine.
I think you may have something simple like a fluid leak, Check it, running and hot.
I tend to doubt it's the tranny unless you are really unlucky and have the dreaded Valeo radiator which leaks coolant into the transmission. But again, a full flush is the 1st thing to be done along with replacing the radiator.
https://mbworld.org/forums/2254029-post59.html

C230 Sport Coup

WallaceLau

Hello guys,

Thanks for all the notes!! And I've got some update! Girlfriend decided to tow it to a dealership because towing is covered free of charge from the MB roadside assistance. (Yeah, I know, probably a mistake.) Dealership reported this:

"FAULT CODES STORED FOR TRANSMISSION IS SLIPPING
AND INTERNAL FAULT OF EGS CONTROL MODULE. CHECKED FLUID LEVEL AND
CONDITION. APPEARS TO BE FULL BUT IS BURNT. TRANSMISSION IS LEAKING AT
PILOT BUSHING AND DRAIN PLUG AS WELL"

So yes... leaky pilot bushing but still with good transmission fluid level. HOWEVER!! Based on the above diagnostic, their recommendation is a full rebuild at $7,600. So, unfortunately, it seems the dealer just wanted to charge as much as they can. We will likely be taking the car back and I will start some DIY, especially after I get some feedback from you guys on the above diagnostic. Also, now that she knows the car is a lost-cause (at the dealer at least), she can't blame me for making it worse!! (The car is only worth about $5,500 on the open market, by the way.)

Now here is the confusing part. The dealership said 39,000 mile transmission fluid change is "required". And as you've pointed out, nowhere in the manual said transmission fluid change is required for the life of the vehicle. Since the purchase price of all 2002 MB (up to 2005, I think?) includes "required" maintenance during the warranty period, which is 50k mile, wouldn't it mean the "required" transmission fluid change as claimed by the dealership is supposed to be included in the maintainance package that comes with the car? Do we have the ground to argue that because the dealership failed to perform the free/included maintenance, they should pick up the tab on the new transmission? She said she can small a class action suit coming.

In any case, I take that if the transmission fluid level is still good, we couldn't had possibly do too much damage to the tranny... if we can't get the dealer to bulge I'd tow it back and start tearing into it. The instructions posted by you guys are easy enough to follow, I don't think I will have any problem checking all of them.

Will report back as soon as I can! Stay tuned...

Thanks,



Wallace

WallaceLau

Yes I've been stalking for a while... actually been on-and-off ever since she bought the coupe, but never had to post since I was able to get most of what I needed from just reading. Until her transmission blew, that is... I found some good posts but I decided this is one area I want to get some first-hand expert opinion before I screw around in her car. (pun intended??) ;-) Will update my profile shortly!!

Well that mechanic is now long gone! And so will the dealership!!! Actually, turns out my mechanic doesn't have the STAR diag. tool to read the transmission, so he sent it to the back-alley transmission shop next door which quoted him $4000. He has been good and honest on my Honda, very reasonable price, but I think the Benz is just out of his league. But in terms of the girlfriend... that might be a little difficult to get rid of...



W.

Glyn M Ruck

As far as I'm concerned MBUSA has much to answer for with filled for life comments that they then changed to change once at 39K. We have just such a case on the 209 forum where a Canadian car is at 150K miles & the dealer is still shouting filled for life.

ROW has always been every 39K miles or 60K Km's. I posted Vietnam as an example for 209 forum.

I don't know US law well enough to know if you have a case. In countries that sell the cars with Mobilodrive (Motorplan) the cars get changed every 39K miles 60K Km's on Benz' dime.

LILBENZ230

Of course it is. Did you expect anything less from the dealer? They don't do repairs. They replace parts.

Get the fluid flushed, change the leaky pilot bushing, fix the leak at the drain plug and see what happens from there.

WallaceLau

Hee hee hee, hence forth I said "So, unfortunately, it seems the dealer just wanted to charge as much as they can." Feel the sarcasm?

When I had my old Celica, the Toyota service department is really good at saving me money... the guy even show me where to get wiper blades so I don't pay $25 per set at their parts store. But I guess MB expect all their buyers to be filthy rich!! Too bad we are no where near that.

Anyway, to everyone who had chipped in: THANK YOU!!! I will be getting the car back and making fluid changes etc... I will report back in a week or so, once I have time to get under it.

Thanks!!



Wallace