My 90 has developed overnight, a stiff steering wheel, then it will free up and all will be fine for 100 yrs, then stiffen again. I've checked the fluid level, thats ok, there are no leaks, i've looked in fluid res while putting steering lock on both sides, there is a shimmering of the fluid, but i cant tell if its moving under the vibration of steering lock being applied.
Pump buggered ?
Pump buggered ?