The plugs were dirty and almost no electrode left and I had to soak the back plugs in WD40 so I dont really know if #8 had oil on it. The worst ones were actually in the front of the engine and I dont have oversized tires. The strange shifting issue popped up at literally the same time the misfires, and loss of power happened. My mechanic doesnt want to delve into the trans yet and I have all of the symptoms of a shot plenum gasket so we're going to tackle that first and see where my truck ends up from there.

 

Misfires and a crappy running engine CAN cause trans shift issues since it's not running where it should be.

 

Plenum fix, full tune up, cat replace, new o2's. Nuff said.

 

How many miles are on this thing? I'm surprised no one has asked... All these symtoms sound like they can be from a worn out drivetrain.... I agree if the engine isnt up to par shifting points will be effected..

Of course I'm assuming you took care of ALL the basic obvious tuneup stuff first like new wires,cap rotor,and air cleaner along with that new pvc....

Being that the plugs havent been changed since Jesus was a boy and were frozen into the block I'm fairly confident the truck wasnt properly maintained and could be suffering the consequences.... If the plenum was really the cause the ancient plugs should have fouled out long ago....