Hello all,

New to me owner of a 78 300SD T/D. PO seemed to take very good care of the car and even with 340K on the clock it's a pleasure to drive. So I'm trying to make sense of my shifting problems. I'm finding that in order for it to shift upwards, I have to let off on the throttle. Is this considered a "hard" shift of a "soft" shift? Any advice as to why you think this might be so. I will check all my linkages and see what's what...but a general idea of why this is happening would be most appreciated. My locks all work well, car shuts off quickly and all vacuum items "seem" to work. I've checked my fluid and it's not burnt and looks and smells good. Car goes down the gears no sweat. There seems to be little to no lag time when I shift into gear or reverse. Also...what RPM's should I be looking at with this trans and engine (617.9) I'm getting 3000RPM at 65 and about 3200 rpm at 70, does this sound right?

Your help is appreciated.
Thank You
Duke1

Rpm's are correct. Do a search on 'bowden cable'. You don't have a cable but a rod. The function is the same. It controls shift points. Vacuum controls harshness or softness of shifts. It doesn't sound like you have any problems there, just in the shift points. A stuck kickdown switch will also push shift points upwards.

__________________
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

Both my 722.1 have no cable or rods....

Its all done with vacuum on mine....

Vacuum is critical to their operation....

__________________
http://i190.photobucket.com/albums/z...0TDnoplate.jpg

Alastair AKA H.C.II South Wales, U.K. based member

W123, 1985 300TD Wagon, 256K,
-Most recent M.B. purchase, Cost-a-plenty, Gulps BioDiesel extravagantly, and I love it like an old dog.

W114, 1975 280E Custard Yellow,
-Great above decks needs chassis welding--Really will do it this year....

I don't know what the number of my tranny is, but my 79 116 SD has a rod. His is a 78 so I assumed it would also have a rod. I know there are transmission solely controlled by vacuum but I thought all of them were on non-turbo models.

__________________
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

Ah, Maybe....

All mine have been and are N/A....

We never got the Turbo in the UK, for some daft reason!

__________________
http://i190.photobucket.com/albums/z...0TDnoplate.jpg

Alastair AKA H.C.II South Wales, U.K. based member

W123, 1985 300TD Wagon, 256K,
-Most recent M.B. purchase, Cost-a-plenty, Gulps BioDiesel extravagantly, and I love it like an old dog.

W114, 1975 280E Custard Yellow,
-Great above decks needs chassis welding--Really will do it this year....

Kerry,

Thanks for the reply...I will search for Bowden Cable. I do have the rod from the top of my valve cover to my transmission. So by searching above words..this should tell me how to adjust this rod? Also wondering what the dots are for on the speedo. I'm assuming their shift points? One dot means out of 1 and into 2 and so on?

Thanks,
Duke1
(Mike)

The dots are the MAX speed for that gear. Not when they would shift. After all, the shift point is based on rpm, speed, load, etc. Not just speed alone.

__________________
1991 560 SEL / 185k miles
1992 750il / 17k miles - project car

Yes, tightening or loosening the nut at the end of the rod at the valve cover changes the length of the rod and moves the shift points.

__________________
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

Thanks for the info. So should I adjust it in or out so to speak to make it shift without taking my foot off the pedal?

So I adjusted my control pressure rod in (shorter), and adjusted the trans modulator to less pressure and it will now shift nice and smooth. My question now is shift points. 2 to 3rd gear does not shift until 35mph @3500 rpm. 3-4 shifts at 55mph @3500, unless I back off on the throttle. It shifts briskly, but not harshly. Are my shifts points too high? If so, I would adjust this with the contol rod?

Your help is appreciated.
Mike

you could have a stuck downshift button under your fuel pedal.

__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!