Q: Car is losing power and shaking

asked by on October 24, 2016

I have a 1998 Mercedes Benz c230, it feels like the u joint is bad, viberates real hard right under the center console, but also now the car wont take off as fast, uses way too much fuel and when it viberates , sometimes it viberates so hard the engine will shake. Im not sure if this is just one problem or more than one. The air filter is bad, I need to change it, oil is good, im not sure on spark plugs im sure they are not too good. Car has over 126k on it. Sometimes when I hit the gas it gets loud but barely pulls. Also there is a tone of oil under the car, most of the undercarriage is covered, its not motor oil. But there is no way to chek the transmission fluid with out taking it to a dealer,, any advice on what may be the problem?

My car has 260000 miles.
My car has an automatic transmission.

Hello. Your intuition is correct. Your vibration is caused by a failing "flex disk", a large rubber and steel "doughnut" which connects the transmission and driveshaft, and acts as a u-joint to allow flexing as the engine and transmission move about. Once this disk starts to deteriorate, it can fail quickly, so don’t delay having it replaced. The transmission fluid CAN be checked on your C230, even by you if you are a DIYr. This is a filler tube at the rear of the engine, but there is no dipstick and requires you to buy a "service tool" (really a dipstick-like metal rod), which is temporarily inserted into the filler tube to check the transmission fluid level. By all means, have the fluid level checked as soon as possible. A low fluid level could well be the cause of poor acceleration, and could be causing damage to the transmission. If you would like to have this checked for you, a certified technician from YourMechanic can come to your car’s location to inspect the loss of power and vibration problem in person so that this can be corrected.

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