Just picked up a new project car, god help me.... 1992 300D 2.5 TD with 200K on the clock.

The trans shifts fine and engine runs strong until it shifts to 4th and the engine just revs freely with no apparant engagement of the trans in 4th gear. If I manualy shift to 3rd the trans re-engages in 3rd and drives fine 1-2-3.....

no 4th gear at all, it acts like the trans is in neutral when it make the 3-4 shift.

I just got the car today like this. Hey, it was cheap...guess not

anyway, the trans fluid was way down so it was driven a while like that I think. Took 3 quarts to get it up to normal level. Dark dirty red color too.

The engine runs strong and trans is smooth and shift 1-2-3 OK, just no 4th gear.....

Suggestions ????

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1987 300TDT
1981 VW MKI Caddy 1.6 diesel, waiting on engine swap
1983 D-50 Power Ram 4x4 "Mitsubishi" 2.3 turbo diesel
assorted gas powered crap and motorcycles

RIP: 1984 300TDT, 1982 300TDT, 1984 190D 2.2, 1992 300D 2.5, 1987 300TDT, 1982 Maxima LD28, 1983 Maxima LD28, Isuzu C223 P'ups X3, 1983 Holiday Rambler 6.2 Banks turbo diesel, 1984 Winnebago LeSharo 2.1 TD, 1985 Allegro 6.5

Change the fluid and filter.

Sixto
87 300D

tomorrow, cold & rainy today :-(

will a restricted filter cause 4th to completly slip while 1-2-3 seem normal?

__________________
1987 300TDT
1981 VW MKI Caddy 1.6 diesel, waiting on engine swap
1983 D-50 Power Ram 4x4 "Mitsubishi" 2.3 turbo diesel
assorted gas powered crap and motorcycles

RIP: 1984 300TDT, 1982 300TDT, 1984 190D 2.2, 1992 300D 2.5, 1987 300TDT, 1982 Maxima LD28, 1983 Maxima LD28, Isuzu C223 P'ups X3, 1983 Holiday Rambler 6.2 Banks turbo diesel, 1984 Winnebago LeSharo 2.1 TD, 1985 Allegro 6.5

It probably wont help, but it is worth a try.

__________________
1959 Gravely LI, 1963 Gravely L8, 1973 Gravely C12
1982 380SL
1978 450 SEL 6.9 euro restoration at 63% and climbing
1987 300 D
2005 CDI European Delivery
2006 CDI Handed down to daughter
2007 GL CDI. Wifes

did it just happen or was it bad when you first drove the car?
larry

I'm with Sixto - change the fluid and filter and see what it does then. You may even want to try some TransX additive too.

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Jim

it was like this when I got the car. The thing would hardy move. I checked the trans and the dip-stick was dry. The engine ran smooth and reved nicely.

So I dropped a grand on the car and went to get some trans fluid. took over 3 quarts to get it to read normal. His teen daughter was driving it and looks like a typical teen car inside.

anyway, 3 quarts and she dropped into gear and took right off very nicely...it's just when she shifts to 4th it just revs up and goes nowwhere, kinda like reving in neutral.

Manually shift to 3rd and she drives great around town, just kinda high rpm cause no 4th.

__________________
1987 300TDT
1981 VW MKI Caddy 1.6 diesel, waiting on engine swap
1983 D-50 Power Ram 4x4 "Mitsubishi" 2.3 turbo diesel
assorted gas powered crap and motorcycles

RIP: 1984 300TDT, 1982 300TDT, 1984 190D 2.2, 1992 300D 2.5, 1987 300TDT, 1982 Maxima LD28, 1983 Maxima LD28, Isuzu C223 P'ups X3, 1983 Holiday Rambler 6.2 Banks turbo diesel, 1984 Winnebago LeSharo 2.1 TD, 1985 Allegro 6.5

Change the rear end ratio to get the revs down. Seriously though there may be a band adjustment for example for that gear. I have heard of adjustments backing off sometimes on earlier mercedes automatics.
If there is a local guy that works on your type automatic from time to time you might want to at least talk to him.
Also have a look to see if you can establish where the oil has been leaking from this transmission. Slight chance it might provide a clue. At least in your area there might be a good used transmission available at a reasonable price if it comes to it. I wish we had pick and pulls around here from time to time.

well, I got the filter and fluid changed this weekend. The trans fluid looked black like oil, probably never been changed.

Anyway, it didn't help any. Still shifts fine 1-2-3 then 4th just revs freely like it's in neutral.

4th just slips & slips. It does not even seems like it's trying to engage.

Is there some kinda solenoid or other engagement mechanisim, cable, vacuum line for 4th gear?

Is there a top vent on the trans? I filled the trans and after about 5-6 quarts it starts leaking big time. I get under the car and the leak is at the driver side rear of the trans and much higher than the pan gasket area. I'm guessing that since I didn't start the car after the first gallon of ATF, the torque converter was still dry and the main body was thus over filled and can out some air vent.

__________________
1987 300TDT
1981 VW MKI Caddy 1.6 diesel, waiting on engine swap
1983 D-50 Power Ram 4x4 "Mitsubishi" 2.3 turbo diesel
assorted gas powered crap and motorcycles

RIP: 1984 300TDT, 1982 300TDT, 1984 190D 2.2, 1992 300D 2.5, 1987 300TDT, 1982 Maxima LD28, 1983 Maxima LD28, Isuzu C223 P'ups X3, 1983 Holiday Rambler 6.2 Banks turbo diesel, 1984 Winnebago LeSharo 2.1 TD, 1985 Allegro 6.5

How did you fix your 4th gear? I have the exact same problem on my 93 2.5 300d...PLEASE HELP!

He never said it was fixed. His 4th gear is gone, same thing is pretty much happening to my car as well.

Just another reason, to put my car in retirement.

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1998 Ford Escort ZX2 5 speed - 279,000 miles My Daily

1992 Mercedes 300D 2.5 202,000 - Pure junk
2000 Mercedes E320 Black - 136,000 miles - Needs repair

Don't forget to grease the screw and threads on the spring compressor.

Running low on cool and weakens pressure on the clutches... causing rapid material failure.
Need to replace or resurface steels and clutches...
Trans tear down time.

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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 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

As Bob Dylan put it:

"Ain't no use to wonder why..."

This thread is over ten years old.

And yet, this is still how 722.x transmissions die.

frank, enough with that crap already...these cars are pushing at least 30 years old right?The problems are the same as 10 years ago and any thread is still very relevant.