Interesting problem.

Sometimes in traffic my 87 300tdt will not shift from 1st gear. I have to pull over and shut off engine, then restart and it seems to work fine.


I'm checking for vacuum leaks but can't find any. What else can I check.

Could this be a bowden cable issue?

__________________
1994 Toyotal Landcruiser 220k (Sold)

1987 300TDT 278K My Addiction (Going Going Gon...)

2001 Volvo V70 (New Ride)

Could be the bowden cable sticking. Might also be a stuck kickdown switch.

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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

Thanks for the response. I'll definitely unhook my kickdown switch.

Is there a way to oil the bowden cable? Can I just put some motor oil at the top and let it trickle down the bowden cable housing?

__________________
1994 Toyotal Landcruiser 220k (Sold)

1987 300TDT 278K My Addiction (Going Going Gon...)

2001 Volvo V70 (New Ride)

It's worth a try.

__________________

"Buster" in the '95

Our all-Diesel family
1996 E300D (W210) . .338,000 miles Wife's car
2005 E320 CDI . . 113,000 miles My car
Santa Rosa population 176,762 (2022)
Total. . . . . . . . . . . . 627,762
"Oh lord won't you buy me a Mercedes Benz."
-- Janis Joplin, October 1, 1970

Move it by hand, should move freely and smoothly.

__________________

Gone to the dark side

- Jeff

Better ATF than motor oil.

Sixto
87 300D

I just purchased a w126 and its exhibiting a strange (to a MB newb like me) shift issue. I've replaced a bunch of rotten vacuum lines and am now able to feel vaccum on the input line to the transmission. However the vehicle won't shift out of 1st unless I get it up to about 25 mph then manually shift to Neutral then back drive. Then, if I'm very light on the accelerator, it will stay in what seems like 3rd gear. It shifts down to first if I load it much at all. 722.32x trans.

wdawson61, ould be nice to know what kind of 126 you have (year/model).

There's a switch at the far end of throttle pedal travel. Remove the switch and see if things improve.

300SDs have a cable that comes up the passenger side of the engine to a system of bell cranks on the valve cover. The cable ends in a rubber accordion section and a ball socket. Check that there is a little bit of slack in this cable when the throttle pedal is in the idle position. 300SDLs, 350SDs and 350SDLs have this cable come up by the oil filter. Same check.

Sixto
87 300D

my 603 sometimes gets stuck in 1st, it has always meant low on trans fluid. I add a quart or so, runs fine again. gotta fix that pesky front seal on trans, its dripping red all over my garage

__________________
Paul
Benz-less
I need an SDL !

Check the level of your transmission fluid. Read the manual to see how to do it properly. In the old days you put on your parking brake, left it in drive, and checked the fluid level with the engine running. Do not do that any more but you should know exactly how to do it.

Could be the kickdown solenoid in the rear of the transmission sticking. Maybe some type of transmission treatment?

__________________
Michael LaFleur

'05 E320 CDI - 86,000 miles
'86 300SDL - 360,000 miles
'85 300SD - 150,000 miles (sold)
'89 190D - 120,000 miles (sold)
'85 300SD - 317,000 miles (sold)
'98 ML320 - 270,000 miles (sold)
'75 300D - 170,000 miles (sold)
'83 Harley Davidson FLTC (Broken again) :-(
'61 Plymouth Valiant - 60k mikes
2004 Papillon (Oliver)
2005 Tzitzu (Griffon)
2009 Welsh Corgi (Buba)

I had a similar problem in my '85 300D. I thought it was the modulator valve, ordered a new one and spent 2 hours on my back with a mirror, flashlight, and lots of cuss words changing that out. After my post-op test drive, I started searching the Interwebs and found this thread.

Went back outside, unplugged the kick-down switch under the accelerator pedal and now it shifts again.

Thanks all! (and time reading here is well-spent!)