What could cause a grinding noise when you make a very tight turn in either direction after replacing the steering pump twice on a 1996 Winstar 3.8L if the mechanic says its not related to the pump?

Here are a few thoughts: Fords are whiny in their steering systems, but not grinding. two possibilities that come to mind. One is the steering rack. Having said that I wouldn't replace it because of noise. Second is a product called "Lucas." They have a power steering additive that really works most of the time to quiet or prevent a chatter when turning. Sorry I don't have an answer for you, but my 2000 Windstar does the same thing, and several different dealerships tell me this is just how Fords are which is ridiculous! i know it sounds dumb but check to make sure your mud flaps are fully secured and that the tire is not rubbing on them. it may be the bearing in the upper strut mount which causes a grinding noise. you may also find the sway stabilizer link may need to be changed grinding and clunking noises especially when turning can sometimes be the outer CV joints. Check your lower balljoint.. L & R With '95 and '00 Windstars the Tie rod joints can dry out. They do not have zerk fittings to inject grease but I've had 2 go bad on the driver side (Left). I finally slit the rubber seal, applied 5 drops of Triflow oil (with Teflon) and 3 years later still no noise. Sounds "Mickey Mouse" but Triflow is really a superior lubricant and great for galled up screw extraction. No, I don't work for them in any way! If you do replace the tie rod end simply count the number of turns as you unthread the old one and insert the new one the same number of threads. Alignment will very extremely close for toe adjustment. I had a similar problem with my 98 Windstar, caused by broken front suspension springs, which caused the tire to rub on the spring assembly. If this is the case, there will be a strong smell of burning rubber. There is a recall for the 98 models' springs.