what causes shudder,tork oonvertor or trans.?
Try checking the fluid level changing the transmission fluid. Make sure you use the proper fluid which I am pretty sure is MerconV for your Mercury. There is torque converter shudder and slippage (2 separate issues) when taking off. I am thinking you are having a slipping problem which may be an internal transmission issue, bad burned fluid or low fluid level.
Change the fluid, and they do make an anti-shudder additive. make sure the torque converter is drained. It has a drain plug. Or, have a shop do a complete flush and change.If there is still a problem, try Lucas transmission additive, it can do wonders. This is a common problem.
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