So here goes, if you decide do do it we can talk and I'll be glad to walk you thru it.
At you mileage you are going to have a long list of stuff to do, more then the dealer will do but very necessary. By the way, I have been in the automotive industry for 27 some years, most in service.
List to follow is based on the idea that all needs to be done unless some item was done in the last 15,000 miles.
All fluids, brake, steering, diffs, t/case, coolant and tranny.
Transmission service
Tune up plugs, plug wires, air filter, cap and rotor if you have a distributor,
o2 sensors if you really want all your old power back
Belts and hoses
Fluid additivies for power steering, coolant, transmission, diffs and t/case
All filters
Stuff like that, looks like alot, will take a little time and your truck will be so much happier.
By the way, how long has it been since you changes out your springs and shocks?
Get back to me.
Mike