i just typed this in another similar post.... mine is not a sport, but the same principle applies:
my most annoying squeak were the leaf springs. I first power washed the whole suspensión, rode it a bit, then more washing, waitd for it to dry,
hitted all the suspensión rubber parts with silicon or teflon lube first to protect the plastics from environment and oils and to displace the water that could still be there,
then used some regular transmision oil in metal to metal (got some between leafsprings with a sirynge, and certain pins, then used spray on lithium grease in every moving part, bushing, got some in between the leafsprings to sort of "seal the oil" in there and weather proof it a bit,
also i used the silicon lube in top and in the sides of every body mount (helped to eliminate the squeaks and cracks when the body flexes like in ramps or diagonal bumps, etc),
lubed and tighten the spare tire winch, and after that... took it for a ride, tried to brake suddenly, sharp turned, bounced it around a bit, to get the lube all over the suspensión.
After this, i only needed to add a bit of lube to the mmmmm front leafsprings shackels?? mounts?? whatever.... and i do this like every 3 to 4 months, and keeps the x completely silent, it´s great to feel that new car clickity, crackly, squeaky free feeling. Also you could get an undecarriage wash and a normal lube in certain carwash places, and it also works, but they tend to use old oil mixed up with diesel to spray everything, and while it also protects you from rust and stuff, the agressive chemicals also dry up your rubber parts.
to locate an specific problem, have someone bounce down the truck, while you are under it, and touch mobile parts, you will "feel" the squeak.
This works great for me, but i´m not a continuous off road kind of guy, maybe if i did i would havve to do this more often. hope this helps.