poly control arm bushings
I replaced the old rubber bushings on both upper and lower control arms with polyurethane bushings on my 1990. It made the front end slightly tighter, but nothing like replacing tie rod ends and ball joints. I DO NOT like the harshness- I run Bilstein shocks, which are slightly stiff on small cracks and irregularities but great on larger stuff- the result is a lot of sharp movement transferred to passengers. On the other jeep, if needed, I will go back to rubber. An advantage of poly is that you leave the metal sleeves in the arms. By heating the rubber and sleeves, the old rubber will slide out (hit it with a rod/hammer combination). This makes a lot of smoke and bad smell. Then the poly, after spending the night in the freezer and lubing with the silicone goop, taps in nicely.