Went to the track on Sunday, Along with a couple of my mustang buddies, my friend don with his 2004 FX4 supercrew ran also. (which made be not look like the loner with a stock pickup at the track).

Mines a 2004 Supercrew lariat 4x2
Sunroof
power slider
audiophile
center shift
towing package
bed extender
bright step bars
3:55 LS

Ran best of two: 16.43 @83.6MPH

It has 1900 miles on it.

His is a 2004 FX4 supercrew (4x4)
Mirror package
sliding window
center shift
black step bars
3:73 LS

Ran best of two 16.60 (I dont know MPH)

It has 4800 miles on it , also has the Air raid Cold air intake (awsome looking kit)

I'm thinking mine was a little quicker due to his added weight of the 4x4 set up

 

You might have had an advantage with the 4x2 setup, but your buddy had the 3.73 gearing, which probably negated the extra weight in acceleration times.

Just a thought,

- Justin