Oil Capacity Vs. Dipstick

[shadoow]

i bought a used 07 chev 3500hd D/A DRW. Drove it about 60-70 miles home from the dealer & checked the oil dipstick once i got home. The oil level showed a couple of inches above the level piece (i.e. it was a couple of inches up on the cable itself). I let it sit overnite & checked it cold the next day & it was still showing about 1.5" up on the cable. I drained enough oil to get the reading to the middle between the A & F marks on the dipstick....turned out to be a gallon or more!!! I decided not to drive the truck until i completely drained the remaining oil and refilled it. I drained the remaining oil tonite & it was about the same amount as i originally drained, maybe a little more. Based on the amounts i drained, it looks like it had the right amount of oil in it. Can the dipstick be that far off??? I'm going to add oil in the morning as it's too dark to do it tonite. I've always heard to make sure to add 10 qts. on an oil change, but having it show so high on the dipstick doesn't seem right either. Any insights ??

 

thanx for any help