I recently swapped my original motor and tranny with and F22B DOHC and Automatic transmission. Under relaxed driving/low torque the shift into third gear, and sometimes 2nd gear, a very hard and dense BANG occurs and feels like its near the hydrolic mount area. It feels terrible. The intensity of the bang varies between a light thud to a very dense and hard BANG that can make my dash board jump. If I drive more heavy footed it shifts smoothly...
​​​​​​​And again..this only occurs when gently driving on city streets where accelleration is calm and tops out and shifts into third at about between 40-45 mph.
​​​​​​The mounts are all fresh with the swap...I have been driving it one year with this swap and am starting to wonder about that hydrolic mount not functioning properly but I am only guessing. Inspecting them I found no cracks or signs of improper installation.
I have driven this car for twenty one years and never experienced this bang until the swap.


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