rear springs and Steering

[Teamvi]

I m thinking my rear leaf springs might be wore out, truck has 250K on it. I occasionally tow with it on the weekends usually 8k or so. Just feels like it rides ruffer then it use to. Anyone replace these or upgrade? do the bushings go bad often or springs and everything just wear out. its a 2005 gmc sierra crew cab 2500hd with the 4+1 stock springs.

I have upgraded the steering to kryptonite steering and tie rods. alothough have stock power steering that was replaced about 100k ago with one from a junk yard. Ball joints and wheel bearings all feel tight. however I get slight steering wheel shake at 50 mph or so, seems to go away on corners. Any ideas what it might be? take hand off the wheel and it drives fairly straight. running fairly new 285/55r20 michey thompson A/T tires.
Thanks

[2004LB7]

Yes, springs can wear out but it normally takes lots of hauling, loads or cycling of the leaf pack

It is usually visible from the sagging it creates when lightly or unloaded. Another item to check which is more common is the shocks.

For the shake in the steering, check for looseness in the linkage and stabilize. Jack up the wheels and check the wheel bearings. And finally check the Ballance of the wheels. You may have lost a weight or two

[Teamvi]

I have checked the wheel bearings and ball joints, there tight...