Sounds like clutch related vibration, chatter Did you possibly get some oil or other oil based liquids on either the clutch disc, pressure plate or flywheel? If so that may be part of the problem
I've had the Assy. apart twice looking for those things. Non found.
1968 Barracuda Fastback 318-2BBL 904 2.76 Frost Blue Survivor 1970 Roadrunner 440+6 BBL 727 AT 4.10 SG Dana Blue Fire Metallic 1971 Cuda 340-4 BBL 4spd 3.91 SG Curious Yellow 1972 Barracuda 318-2 BBL 904 AT 3.23 1 Legger Tor Red/White Vinyl Top 2007 Dodge Ram 1500 5.7 Hemi AT Patriot Blue 2011 Dodge Challenger RT 5.7 Hemi 6spd 392 SG Triple Black 2014 Dodge Charger RT Max AWD 5.7 Hemi AT 305 Billet Silver
