300SDL troubles (0/1)

I had the transmission replaced about 55,000 miles ago and when the car was in for its last service (355, 000 miles on car) I had them do the transmmission service as well. When i first got on the freeway i
could feel something strage when under full acceleration it tried to shift from 3rd to 4th. It was jumpy, like it didn't know if it wanted to shift or not. I let off a little and it shifted fine. I figured it was because the transmission was cold so i didn't think much abou tit. A few weeks later, it started doing it between other gears as well. I checked the fluid and there was too much. I drained some out to the proper level but i am still having the trouble that, even if not under full acceleration, the transmission does not want to go into the next gear unless i let off a little bit. In this first pic (i believe is the transmission control valve?), if i take the bottom hose off, the transmission does not pull as hard and i still have to lift off to get it to shift, but it does not have that jumpy feeling.
While looking for a vacuum leak, i came across another problem. Next to the brake master cylinder is a large vacuum hose and there is a branch off it (pic 2) that has been plugged. It looks as though the top of the part in pic 1 haqs been plugged as weel. There are only 2 hoses attached but there are 3 ports. I do not know if these lines are suppose to be connected to eachother or to other things or what they even control. I can see no loose hoses that have been plugged that would attach to either of these locations mentioned. Any ideas where to look or what to test? Anyone have a vacuum diagram for a 300SDL? TIA Shannon 86 300sdl 357,000mi 80 450sl 220,000 mi
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valve is listed as a vacuum change over valve. What does it do?
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I would say it is probably a vacuum problem. First of all, get a vacuum gauge and test how much vacuum you have. Test it at the vacuum pump first...
I can't see the picture as I think is a large file. Even with cable modem, it didn't load up. You should consider posting it on a host... like Kodak pictureshare or something similar...
Who serviced your transmission?
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control valve is really a "vacuum change over valve". What does it do?

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Mmm... I need to look at my friend's 300SDL to see how it is, but your best bet is to get a vacuum schematic to make sure everything is the way it should be.
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This isn't the first time that I've heard of folks having trouble following having their transmissions serviced. Under normal operating conditions, I would not do a fluid and filter change until 100,000 miles. IMO, it's just another opportunity for something to go wrong, like accidentally introducing some dirt, etc in the process. Also, many of the shops now do it via a power flushing process, which is supposed to get all the fluid out, but I'd be a little leary about.
If it were me, when I found the tranny was behaving strangely upon leaving, I would have checked the fluid level and then gone straight back to the shop to document that you noticed the problem immediately.
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It's very bad advice to not follow the recommended service schedule for your transmission if you plan to keep the car for a long time. If you drive on pavement, change the transmission fluid and filter every 30,000 miles. If you drive on gravel roads or under very dusty conditions, service the transmission every 15,000 miles. At least that is the recommended schedule for my Mercedes.
I have a 1982 300 TDT with 408,000 miles on it. I bought the car in 1993 with 144,000 miles on it. I bought it after the original owner had just replaced the transmission for a 2nd time. I suspect they were not servicing the transmission as per the recommended schedule.
I have followed the schedule above and have had no trouble with the transmission that was in the car when I bought it and I have driven over 250,000 miles with it. Not long a go I met a friend who is a diesel mechanic in Las Vegas. I had left my Benz at an airport parking lot and he flew in a couple of days before me and used my car for a couple of days and he commented that the transmission shifted "like new."
I use Amsoil synthetic transmission fluid now, but I used Chevron dinosaur tranny fluid for most of the time I have had the car. It shifts with more authority and a bit smoother with the synthetic. I did not notice an increase in fuel economy when I changed to Amsoil.
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wrote:

If i remember correctly, the normal transmission service interval for my 300SDL is 60,000 miles, so i had it done 5000 miles early.

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wrote:

mounted behind the ABS box on the drivers side fender. This one has 3 lines attached to it, one of which comes from a round part attached to the back of the injection pump. There are two lines coming off this part and with the engine running there is only vacuum from one. The other has a 3 way connector on it and one split goes to the change over valve behind the ABS and the other goes to a round blue vacuum contraption also mounted just behind the ABS box. The top of this blue canister has 2 ports labeled TRANS andVAC. I have found that when the transmission starts acting up, i can take the hoses loos from the splitter (one to the blue canister and the other to the vacuum change over valve) and the yellow hose connectors are wet with motor oil. If i clean them off and re-attach everything, the transmission does better for a few days. How is oil getting into a vacuum line? The entire splitter (about 1 inch rubber in ech direction) was covered in oil and the outside of all the vacuum lines in this small are are covered in oin, almost like it was leaking from somewhere else and was blown onto the hoses, but the fender wall and ABS and everything else nearby is bone dry, just the vacuum tubes and connectors. So much so that even after wiping them off it is hard to tell the color codes on them to match them up where they attach on their other ends. The vacuum change over valve from the first pic connects to the top of the engine on the drivers side. This hose also has no vacuum with the engine idling and when removed from the engine end or change over valve end, it is slightly wet with oil. Before the service was done, i never had any trouble with the transmission. They also did an oilchange service when they did the transmission service. Is there any way something they did could cause this or is it just coinsidence?
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