Adjusted Valves & Trans shifts smoothly

[Mercedes Man]

My 1984 300SD has 230,000 miles. I have driven it for only 700 of the 230,000 miles. Today, I finished adjusting the valves. The job would have been easier if I had the correct wrenches. I used a 17mm crowsfoot wrench with a 7" X 3/8" carriage bolt bent to a 45 degree angle as a handle. Along with an regular open ended wrench, the job took most of the morning.

I noticed before the valve adjustment, the transmission had a definite firm shift. I found that I really had to let up on the accelerator pedal to get a smoother shift. I thought the firm shift is common in Mercedes. After the valve adjustment, the transmission shifts as smoothly as the GM hydramatic transmissions that I am used to. I can put my foot on the accelerator and rev the engine to 2000 rpms and the transmission shifts smoothly when ever it hits 2000 rpms. The acceleration is just fine. I can feel 1st gear shift, but doesn't shift hard. The rest of the gears I don't feel, but I can see the shifts happening in the tach. Does anyone know why the transmission shifts so smoothly?