W124 722.4 Transmission Acting Up
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1987 Mercedes-Benz 300D
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Hello friends,
I have a 1987 300D (non-turbo) with the 4 speed auto like everyone else. This morning for some reason out of the blue, the transmission changed its shift points. I know the 722.4s start in 2nd gear, and roll through 3rd and 4th pretty quickly. Today upon take off, it starts in 1st and accelerates quickly through 1st as if i had stamped on it upon take off (not *** jarringly, i will note), and the 2nd, 3rd and 4th. It's for some reason very touchy now to acceleration between 3rd and 4th gear. If i step on the pedal to pick up speed while in 4th and cruising, it quickly downshifts to 3rd and rips me up to speed. Before it would naturally use 4th gear to accelerate and only downshift if i gave it some good throttle.
The only thing that has changed in the past 2 days was that I removed the valve cover yesterday and painted it throughout the day, placing it back on the car after letting the paint cure overnight. I did have to disconnect the throttle linkage that goes overtop of the rear section of the valve cover. When i did so, it freed up the linkage from being solid (due to time and gunk im sure) It pulls the throttle the same, but upon returning back to idle it APPEARS (im not actually sure if this happened previously or not) that it retracts more slowly. I cannot tell from depressing the throttle quickly at all if anything has changed, because it doesn't feel or sound like it has.
I know its a vacuum operated system and that a change in vacuum pressure could illicit a change in shift points, but from a valve cover/throttle linkage change seems unlikely. Anyone have any good experience with these 722.4 transmissions, and could help me troubleshoot? Or know them well enough to help me get the shift points back to normal? it would be greatly appreciated.
Thanks much friends.
I have a 1987 300D (non-turbo) with the 4 speed auto like everyone else. This morning for some reason out of the blue, the transmission changed its shift points. I know the 722.4s start in 2nd gear, and roll through 3rd and 4th pretty quickly. Today upon take off, it starts in 1st and accelerates quickly through 1st as if i had stamped on it upon take off (not *** jarringly, i will note), and the 2nd, 3rd and 4th. It's for some reason very touchy now to acceleration between 3rd and 4th gear. If i step on the pedal to pick up speed while in 4th and cruising, it quickly downshifts to 3rd and rips me up to speed. Before it would naturally use 4th gear to accelerate and only downshift if i gave it some good throttle.
The only thing that has changed in the past 2 days was that I removed the valve cover yesterday and painted it throughout the day, placing it back on the car after letting the paint cure overnight. I did have to disconnect the throttle linkage that goes overtop of the rear section of the valve cover. When i did so, it freed up the linkage from being solid (due to time and gunk im sure) It pulls the throttle the same, but upon returning back to idle it APPEARS (im not actually sure if this happened previously or not) that it retracts more slowly. I cannot tell from depressing the throttle quickly at all if anything has changed, because it doesn't feel or sound like it has.
I know its a vacuum operated system and that a change in vacuum pressure could illicit a change in shift points, but from a valve cover/throttle linkage change seems unlikely. Anyone have any good experience with these 722.4 transmissions, and could help me troubleshoot? Or know them well enough to help me get the shift points back to normal? it would be greatly appreciated.
Thanks much friends.
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