Are you sure the growl is coming from the transmission? The symptom you're describing is usually a sign of a failing pinion bearing in the rear end. It starts out as a growl on deceleration, and will eventually start making noise on a pull as the bearings get into worse condition. There will be little or no noise on a "float" where you're neither pulling or coasting.
Jerry


"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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