Hello, I have spent some time searching out different questions about these transmissions. I believe the transmission in my car is a non-vacuum type. I'm not sure if it is shifting properly. When cold it will shift @ 20 - 30 mph, and then again @40 - 50 mph this is shortly after start-up and on the highway. I am assuming it is starting in 2nd and this last shift takes it to 4th. When it is warmed up it seems to shift a little earlier, and when in town it seems to shift earlier as well. I adjusted the fluid level as it was too high. I had a look underneath and found the bushings to be missing on the linkage, I imagine replacing these will help. The other question I have is that it has to be in neutral to start, if i leave it in park and the car rolls I can hear a click...click. I'm not sure if this is something that can be fixed with the transmission in place. The car is a recent purchase and the transmission was rebuilt about 140, 000 miles ago. Hope this is enough information to base a reply to and I appreciate any input. Thanks, Trent.

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67 250S
72 220D
80 300D
93 K1100RS
2000 Jetta TDI

New nylon bushings in the shift linkage will (or should) get rid of the not engaging park issue (rolling in park, not starting in park). If those bushings are gone, the alignment is way off. (Just had these replaced on a different chassis M-B, a cheap and quick fix).

These will not change the actual shifting of your transmission while moving, though. I had a 77 300D (non-turbo) like your car in question, and it shifted similarly. 2-3 and then 3-4 shifts, at about the speeds you mention. It IS a vacuum-controlled transmission (all the diesels are), and any difference in shift firmness etc speaks (most likely) to some kind of variation in vacuum over a range of temperatures. Perhaps a new vacuum modulator would help this?

Just a few thoughts,

JAS