My 300D has 113,000 miles on it. Purchased the vehicle with 109,000 and have always noticed a slip in the transmission when it shifts into 2nd and 3rd gear. I had the fluid changed at 109,000 and have tried additives. I notice that if I manually shift the gears, the slip is barely noticeable. Someone told me that this could be a vacuum related problem. When locking the doors, the actuation is very slow, and the vehicle does not hold a vacuum very long. Can anybody shed some light on this problem?

Thanks
Jerryaldz

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JerryDz

Welcome aboard Jerry.

You have a vacuum leak. Do a search and you will find alot of info about it. In the meantime, look under the hood in the vicinity of the brake master cylinder. You should find some yellow lines teeing off in that area through a check valve. Disconnect it an plug it on the side of the line between the vacuum pump and brake booster (make sure you don't break anything off of that line). Try driving it and see if it makes any difference. If it does troubleshoot and repair the door lock vacuum system. It is doesn't you will need to look for leaks everywhere else. Start at the line between the brake booster and the vacuum pump and go from there. The brown lines go to/through the key switch to the diaphragm actuator on the back of the injection pump. If that line leaks badly the car will not shut off with the key.

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Jim