94 Concorde-Wiper blades streak

During windshield wiper operation, the wiper blades will not clean the windshield properly. On the outer half of both blades, the windshield becomes streaked and is very hard to see through. We have tried new "summer blades" and new "winter blades", and that doesn't seem to help. We have talked to the dealer about it twice, and they say the wiper arm tension is normal on both sides.
The only "wiper arm adjustment" I see in my 1994 Chrysler Service Manual is for repositioning the blades on their pivots. The car has about 120,000 miles, with original wiper arms. This hase become a real safety issue in bad weather.
Do I need new wiper arms or ??????
Thanks for your help!
oldeconcorde

I have the same problem with my 1997, 30,000 on it.
Mine isn't that bad, but can't get rid of ithe streaks.
I hope someone has a fix.

Some follow-up information for Denco:
After a close inspection of the wiper arm, we discovered that the spring which provides tension to the arm to keep it against the windshield was missing!! I assume the spring was there when the dealership looked at it (or at least they said they looked at it), but we had been having this problem for quite a while. Part of the bracket which holds the spring was also gone, and I don't know for sure how the spring and bracket could have been damaged. But when I inspected the arm, it was really loose on the wiper shaft, so I suspect that when the windshield was replaced a year or so ago, the windshield installer botched the replacement of the wiper arm, and that caused the spring and/or bracket to eventually fail. The wiper arm should be very tight on the shaft - it is held in place by a clip and a very small "wedge" that goes between the arm and the shaft to keep the arm locked in position. I suspect the "wedge" did not get put back on the shaft when the arm was replaced by the windshield installer.
So, if your wipers are streaking, and new blades don't help - I would recommend you get a new wiper arm...
Oldeconcorde