strange noise

after wheelin this weekend my xj has been doing some kinda wierd things. first it cranks for 3-4 seconds before starting and idles a little faster/rougher. also when i turn it on it feels and sounds like the engine block jumps like its loose. ( it also does this when i turn it off). i have a thrush glass packs muffler and usually around 45 mph(i dont have a tach) it shifts to 4th and everything starts to vibrate but only when when i stay around 45. that is normal but now it sounds like some loose glass or something is rattling in the dashboard. i did mostly rock climbing and a little bit of mud/water. if anyone has any suggestions that would be nice. thank you.

Check the motor mounts by having someone put it in gear, set the parking brake, hold one foot on the service brakes and step on the gas. Have them do all this while you watch from the side to see if the motor is moving a considerable amount. As far as the cranking time, idling different, etc, pull the inspection cover on the bottom of the bell housing and see if it is full of mud. This can disturb the readings for the CPS.