96 F-150 Drive Train noise

I have a 96 F-150 5.8L with a E4OD transmission and recently I here a pinging noise under my truck when rolling and under very light acceleration. I was wondering if I may have a problem with torque converter? I have recently pulled a 79 GMC Caballero roughly a 100 miles on a heavy duty equipment trailer and have had this noise ever since then. Checked Ujoints and they look fine but u never know with ujoints , but they do not pop under hard acceleration so I have kinda discarded that idea. Any help would be greatly appreciated.Oh and it has a 3.08 running gear.

might want to change the rear diff oil and inspect it if it has limited slip it could need the adtive that will cause some noises in rear end some time u joint might be dry they will cause ping sounds then start sqeekingits best to pull the drive shaft and move the ujoint around for inspection

ok will check the rear end tomorrow although fluid was just changed like 3 or 4 months ago! I will also check ujoints! I was also wondering if it could be the spline shaft bearing since it has 3 ujoints in it, which it meens it has a rubber bushings with bearing in it! Let me know if u have anymore thoughts and will update on my findings. Also forgot to mention my truck has 230,000+ miles on it and all original excluding water pump and tune up items!! It is also Eddie bauer ext cab!