1995 Cadillac STS
Most likely the CV joint is going bad. Just had the same problem, took a guess and replaced it and the problem was solved.
Always check for the simple solution FIRST! When was the last time you balanced and rotated your tires? Very UNLIKELY to be a C/V shaft; it would be noisy.
like logan said it would be a loud thump,mostly only when turning though,,,what exactly do you mean accelerate,upon doing so??or when you reach higher speeds??higher speed wobbles are usually just balancing
And ask for road-force balancing if/when you get new tires. If I recall, the Seville tires were of a new style, so (at least when they were newer cars) the tires may be conventionally balanced, but when put on the car, were still terrible. I purchased my car in 2007, and drove it for a year with this problem, violent shaking around 50-70 mph, then a pause, and then a gentle massage any faster than that. It was so bad that the brake rotors warped (after having them shaved a first time). Finally, after putting new tires on and a few months using the brakes, the tires are still pretty well balanced.
Check the lugs and be sure there are no suspension issues. If on one side only, check the struts and if on both sides check main suspension components.
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