Hello all, I am considering buying a '82 300d with auto. transmission. Man says it slips but just needs transmission oil and filter changed, he says it does that when it has gone too long, past recommended interval for changing. Is this a possibility or could it more likely be something more and if so what and how hard would it be to fix as I usually do my own work if I can. Not real familiar with auto. transmissions though. Thanks, Steve

 

Well, it won't break the bank to change the trans fluid and the filter (if it has one). It may break the bank to repair a trashed trans, though. It wouldn't be hard for me to decide what to do.

Those quick lube places can change the trans fluid in less than 30 minutes for around $50 or so. Make him do it. If he won't and you want the car, you do it before buying. If it doesn't fix it, you're out $50. A lot less than a new trans. If it does fix it and you buy the car, you have new trans fluid.

On the other hand, you may want to run away if he won't change the fluid for you, since it isn't a big deal to get done.

 

Does it slip or does it just flare between shifts??

If it's just flare it may be adjustable. The way I tell if its flare is to manually shift it throught the gears. If it hits each gear nice and firm shifting it manually then more than likely is just flare.

On some of these transmissions adjusting flare is more of an art than a science. The modulator and has more to do with flare than anything else. It is normally not hard to make it shift respectablely unless it's a 1980 240D

If it is the transmission I have a good used transmission out of a 82 300D Turbo. The transmission is a rebuilt unit installed by a Mercedes Dealer less than 20,000 miles ago. I would sell it cheap but the shipping may kill you.

Good luck,
Tony T

 

Thanks for the quick replies and ideas. He is including new filter, gasket, etc. for the fluid change, it is in the back seat. It is a turbo btw. I have not driven it yet and will do so, just wondering how good this transmission is and are there any know issues that can cause this slipping. What exactly is flareing? Thanks, Steve

 

Hi Steve,
Flaring is best discribed as follows: When the transmission starts to shift to the next gear the engine will rev slightly and then feel and sound as if it is sliding into the next gear. It feels like it takes a couple of seconds to drop into gear. Most flaring that I've delt with is from second to third or third to high depending on who you talk to. These transmissions shift twice before they get to second and then once into third so it seems more like a 4 speed automatic. The first two shifts happen pretty close together.

There is a vacuum switch on top of the valve cover that belds/controls the vacuum to the modulator. The little valves ar known to go bad and the little plastic lever the rides on the cam is known to wear off and mess with the shifting also. That little valve is pretty cheap and easy to replace. The modulator is also adjustable but I wouldn't mess with it until you understand what you are doing. There is a good how to on the web but right now I can't remember where I printed it from ----- I'll try to find it and let you know.

Good luck,
Tony T

 

The symptoms you describe are very common for those transmissions.
I drove with them for over 30,000 miles. there is post from other member saying, that his family did 200,000 miles with them, so sounds, like it doesn't affect transmission reliability.
If you can get tranny rebuild by reputable shop, that even better.

 

I think those com on the market in 1985, at least on the models, that I have seen.

 

Be careful changing fluid in an old tranny with uncertain serice history. It can do it in. I agree with prior---sounds like only flare.

 

My 1980 240D has over 360K on it and it has flared every since we've owned it. We just shift it manually most of the time and it works fine. Kajtek1 is correct when he says that it's a very common condition for those transmissions.

Kajtek1, as a point of reference on my statement about the vacuum switch, maybe I should have called it a vacuum valve. My 1980 240D has a single valve with cam follower and my 1982 300D Turbo has a double vacuum valve on it. I may have mis-lead you into thinking it was an electric switch and for that I'm sorry.

Tony T

 

Update! I drove the car today, did not experience slipping or flaring so I asked more about it. Owner says it does it, rpm increase without speed increase, after some period at highway speeds. Will cease after a "rest" period. Could it be the fluid getting hot and thinner? Just a guess. Also the heater did not heat. Anyway, still considering, may ask for substancial decrease in price. I do like the car. I have a cummins diesel in my truck and a perkins in my tractor. The Benz sounds like valves tapping, owner says he had them adjusted once, car has 230,000miles on it. Sound came from area of injector pump, could this be normal? Thanks, Steve