Ok after further review, the thumping noise is constant, doesn't speed up as I go faster. I also notice, when the road is smooth there is a surge that accompanies it. It feels like a misfire, however, that would set a CEL. It is coming from the rear, so I am thinking its the rear clutch pack.
Does anyone know HOW the clutch pack for the rear axle is used by the PCM? Does it cycle under slow to moderate acceleration and Lock in full under heavy to hard acceleration? If so, then this is what I am hearing and feeling. Possible worn clutches? It stops thumping as soon as it hits 5th gear regardless of speed. IOW if I am in forth and accelerating, the moment I lift my foot and it shifts up, the noise completely stops. I also notice that in higher gears, there is NO misfire felt. It is also more pronounced when there is some weight, such as 5 passengers and me in the car.
Does anyone know HOW the clutch pack for the rear axle is used by the PCM? Does it cycle under slow to moderate acceleration and Lock in full under heavy to hard acceleration? If so, then this is what I am hearing and feeling. Possible worn clutches? It stops thumping as soon as it hits 5th gear regardless of speed. IOW if I am in forth and accelerating, the moment I lift my foot and it shifts up, the noise completely stops. I also notice that in higher gears, there is NO misfire felt. It is also more pronounced when there is some weight, such as 5 passengers and me in the car.