On my 2006 Unlimited 6 spd 17,000 miles I've got a chirp sound when I give it the gas... I'll be driving along at say 30 mph, and if I tap the gas I get a quick chirp. The chirp doesn't continue, it only happens one time for each time I tap the gas. Only happens in gear. Sounds like rubber is making the noise, like something twisting from the torque. Only related to pushing the gas pedal, it isn't a continual noise like a u-joint might make.
Have you heard of this before?
PS: and thanks for the link to the Dodge frame modifications, looks like it will be helpful for my project.