I think I am having the simular issue. I would describe it as a bucking. I happens under slight acceleration when the RPMs are low and the trans does not down shift? I want to say it is the torque converter in my case because it only happens under the 2800rpm stall speed of the stock converter.
In my case i do not think it is fuel related issue due no hesitation from the motor.
Give more info on your issue to get more Ideas on what it is.
And if I am way off on this please chime in????
My mm is almost stock too and 90k on the odo.
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