I have an 83 turbo 300d and I have a transmission issue. I've been pouring through forums and people of knowledge all to no avail. The problem is I have no 2-3 or 3-4 upshift. I am a newbie to these but I'm eager to learn. It has a delayed shift into reverse and the gear shifter seems "sloppy." When driving, the shifter is in S but it seems to me that it should be in D1-2 upshift is crisp and firm but nothing else. I've tried adjusting the bowden cable in and out with no effect. Fluid is full and cherry red. Not burnt or low. I'm getting just under 10Hg at the T for the trans as well. Everything else is untouched. Help me?

How many rpm's have you pushed it to looking for an upshift? Have you tried unplugging the kickdown switch? There was a recent post on here describing accumulated debris in the valve body which stopped upshifting.

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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

Not sure on the rpms (inop tach) but I've had it to 50 mph looking for an upshift. I've had the kickdown switch unplugged with no change. I was reading about the allen screw adjustment on the valve body in some podunk forum. Guys said that they have had luck with it. So that was my next step. Has anyone heard of this before? I dont want to mess it up more, although I dont think its possible at this point. But, you never know.

Do you know if the trannie filter has been changed since your ownership? Some people just drop the old fluid out with no filter change thinking that this is service to an old trans,sad to say this just continues a downward spiral of problems including a visual look of service at the stick further delaying the right service needed. In every 30k driven the filter and fluid along with fluid in the torque converter need to be changed out.This gives you a place to start. I do mine once a year and have owned 12 different 300d MBs with no trannie failures except for 1 , 20 months of delayed service stopped it in its tracks.Its a capable DIY job ,just dont do it outside on a windy day since youll have the bottom of the trans opened up.3 small philips head screws hold on the filter ,and 6 bolts for the pan .Youll also want to clean the inside of the pan throughly while down before re-installing .

Imo, fix your sloppy shifter first. there are two round plastic bushing in the shifter assy. and i think two small ones below the linkages. As per your description that your shifter seems to be in the S section, that would cause your transmission to stay in the 1-2 range.

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1974 240D Sara
1977 300D Kristina
1979 300CD Claudia
1984 300SD Helga
1985 300D Pepper

Also check to see if the bowden cable is riding in its sleeve and is not hanging up.I now know one of the trannies signs before failure and that is it was searching for shifts before lose of all gears, slipping but regained itself quickly,a few weeks later nada ,the filter having fully clogged could have been this issue.

Ok. Definitely a place to start. I'm going to order the filter and pan gasket tomorrow. Should have it tuesday and hopefulkly I'll get to work on it then too. As for the shifter, any idea how much those bushings tend to run? I know that its going to vary from dealer to dealer but a ballpark is always nice. Also, should I check for the correct bowden cable position while I have the trans pan down or could this be done at anytime?

you could check on the bowden cable position anytime since it is located above and at the back area of the air cleaner housing. shifter bushings would cost around

2 pcs.

http://catalog.peachparts.com/item.wws?sku=W0133-1643678&itempk=75792&mfr=Febi&weight=0.01

2 pcs.


http://catalog.peachparts.com/item.wws?sku=W0133-1642114&itempk=86518&mfr=OES%20Genuine&weight=0.01

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1974 240D Sara
1977 300D Kristina
1979 300CD Claudia
1984 300SD Helga
1985 300D Pepper

Well, I just finished up the fluid and filter change here at the shop. Took for a test drive, no change Drained TC and trans together and what came out looked more like Lucas slip fix or maybe a combo of trans fluid and motor oil. It had a bluish tint on top of the red color and it wasn't as viscous as trans fluid is. Trans pan didnt have a lot of material in it and filter looked relatively clean. Not too sure what to do now. I ordered the shifter bushings yesterday so they should be in tomorrow or Wednesday. After that, I'm at ground zero again.

These links will help with the bushings.

Broken Neutral Safety Switch and replacing shifter bushings
Broken Neutral Safety Switch and replacing shifter bushings - PeachParts Mercedes ShopForum

Replacing all shifter bushings on W126 - p.1
Replacing all shifter bushings on W126 - p.1 - PeachParts Mercedes ShopForum


This link has enough technical data to rebuild the transmission.

http://www.peachparts.com/shopforum/diy-links-parts-category/142395-transmission.html



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1985 300SD
1983 300D
1984 190D
2003 Volvo V70
2002 Honda Civic

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Ive been looking for a used trannie out of a yard and since the main object is to pull one thats working Ive come to a conclusion to answer this question .Take all the glow plugs out of the motor and test ,if 2 or more or not working then most likely the car sat due to a no start issue and not likely a trannie problem .You can also look at the fuel filters to see if its been serviced lately,if not it could possibly be a result of starving fuel at the pump,another reason for sitting.The chances of finding a wrecked 300d with a good trannie is out their just much rarer ,of coarse this is if your looking to go the cheap route.

I actually lucked out. Ok, long story short. Im 18 and just got through with our local career center automotive program and one of my teachers from there was a Benz tech for like 20+ years. He stopped in yesterday and i asked him about it and he said the seals in the 3rd gear clutch pack are most likely bad causing it to not build enough pressure to shift out of 2nd. BUT, he said he has two of those trans' sitting at his house and I'm buying one for $100 Giddy is an understatement as of now. hahaha. But thanks for the help all!