I'm having a strange rapid thumping on heavy acceleration from a stop. I just finished extensive suspension and engine service, and the thing is tight as a drum. It's a 2004 X 4.0 automatic. I just replaced ALL of the suspension, control arms, springs, bilstein 5100s, full brakes from Mrblaine, extensive engine service, seals, cam gears etc. It has a Ten Factory SYE and CV shaft, and the inside of the transfer case was tight and all bearings were good when I did the SYE install and partial rebuild kit from JD conversions. It also has a freshly installed Savvy TC cable shift.
This noise was also happening before I did the SYE with the original rear shaft. Essentially, when accelerating from a dead stop with moderate to heavy throttle, the jeep jumps off the line, after just a moment there is a rapid thudding (clearly rotational) that sounds like it's right under the jeep. It generally happens for 3-5 "thuds" and stops. If I release the throttle it goes away, and never presents when rolling, even if I accelerate hard from just 3mph or something slow. I took a hard look at the Trans mount when it was out while I was doing the SYE, all of the rear suspension was torqued to spec on the ground, and has all new control arms, track bar, etc. I'm seriously scratching my head.
This noise was also happening before I did the SYE with the original rear shaft. Essentially, when accelerating from a dead stop with moderate to heavy throttle, the jeep jumps off the line, after just a moment there is a rapid thudding (clearly rotational) that sounds like it's right under the jeep. It generally happens for 3-5 "thuds" and stops. If I release the throttle it goes away, and never presents when rolling, even if I accelerate hard from just 3mph or something slow. I took a hard look at the Trans mount when it was out while I was doing the SYE, all of the rear suspension was torqued to spec on the ground, and has all new control arms, track bar, etc. I'm seriously scratching my head.
