After driving on the highway for a distance and getting off at an exit or stopping for any reason there is a knocking sound and engine appears to be missing. This doesn't happen with town driving or driving under 55 mph only after driving on interstate. Problem just started about a week ago but it appears to be getting worse.

SOURCE: 940 GL Stall problem

Check the fuel injection relay

SOURCE: 2001 Subaru Forester with Rattling in engine

it is big end bearing.

SOURCE: engine vibration in drive or reverse

Wow..thats not good..first have motor mounts checked, maybe the tranny mount or possibly if ur car has it is the driveshaft bearings...good luck on the oil leak...maybe tranny fluid..make sure if ur losing fluid that ur checking them incl. the tranny fluid...u might find ur leak first of all by rechecking the oil cap where it is supposed to be ...same with all fluid caps.

SOURCE: I have a 1997 Ford F150 4.6L with an overdrive

You need to have it scanned. The od off light is like the check engine light for the transmission. It will flash when you have transmission codes.

SOURCE: Water pump problemb... or worse??

IF IT IS A 4 CYLINDER U CAN SEE THE WATER PUMP WEEP HOLE(TO THE LEFT OF THE OIL FILTER IN THE TIMING BELT AREA.V6 IS UNDER THE TIMING COVER.EITHER WAY IF THE WATER PUMP IS LEAKING.REPLACE IT BEFORE IT DAMAGES THE TIMING BELT