2003 F250; possible transmission problem

photo: http://i22…acLine.jpg



Truck: 2003 F250 Super Duty, V10, 76k miles, 4R100 tranny (I think)



Background: while pouring oil from a gallon container into the crankcase I felt something catch on the container which I later presumed to be the gray vacuum line identified in the above photo. I reattached the gray vac line after checking pictures of the motor online and in an auto repair manual. Im not even 100% certain this is the correct location of the attachment.



Problems: Noticed immediately after starting the truck and backing up. Problems happen whether the vac line is attached to its current location or disconnected. The issues arent always present and dont happen all the time but when they do, this is how it happens:



- while backing truck will ‘pause’ then the RPMs will drop then surge. The truck jerks as if it were a manual transmission and someone unfamiliar with driving one were trying to get into gear. Stalls at times. Blipping the throttle helps SOMETIMES.



- at approx 30mph-45mph while accelerating there is a grating-sort of sound coming from somewhere in/near the engine. If I let off the throttle it stops then may come back if I accelerate again.



- when coming to a complete stop the truck will do the same thing as when going into reverse…pause, surge, jerk forward, then stall. It doesnt always stall but the RPMs just surge and the truck jerks forward.



- I used a code reader on the OBD-II port and there were no trouble codes listed.



Any input would be appreciated…thanks.