I just finished putting in some AL3923's and did a little seafoaming. Removed the vac line from the brake booster and dumped in a 1/3 of a bottle then put 1/3 in the motor. I bought the truck (01 QC 4.7) with 131,000 miles on her and it ran fine. The PO had taken pretty good care of her, except he never changed out the spark plugs. They had all the 131,000 miles on them. I took the DD out for a quick spin last night after changing the plugs, and man what a difference. This thing pulls like a freight train, I was hoping to get a little better fuel mileage out of her, but now I fear it will be worse as my foot likes to get into the pedal a little bit more because it is a riot! Thanks to the board for all the info that help a newbie get some things done!