FLC OF WEB HAD MOMENTARY DISRUPTION OF VOR DME DISTANCE READOUT ON APCH TO ORD.

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FLYING AS CAPT ON FLT TO O'HARE; CLRED FOR 14R ILS APCH. ILS DME OUT OF SVC. FO HAD JOINED ME ON ILS FREQ; ADVISED HIM TO RETURN TO O'HARE VOR FOR DME READOUT AS ILS DME OTS. I GLANCED OVER AND NOTED 113.9 ON HIS PANEL; DME WAS READING AS EXPECTED. AT A POINT INSIDE WHAT WAS SEXXY INTXN I NOTED NO GS APPEARING ALTHOUGH NO GS FLAG APPEARED. I INQUIRED OF APCH CTL IF ANY OTHER ACFT HAD PROBLEMS WITH GS. NO OTHERS DID BUT ATC SUGGESTED USING GS OUT PROCS. THE COPLT AND I RESET THE BUGS ON OUR BAROMETRIC ALTIMETERS TO 1140 FT (GS OUT MINS) AND SINCE DME SHOWED WELL INSIDE SEXXY I BEGAN DSCNT TO 2400 FT WHICH IS MIN DSCNT ALT TO ROAMY (OM). AT 8.5 DME THE DME BEGAN INCREASING RATHER THAN DECREASING (ROAMY IS 7.5 DME ON THE ILS FREQ) AND ALTHOUGH THE VOR DISTANCE WOULD BE SLIGHTLY DIFFERENT FROM ILS DME I WAS ONLY USING IT AS A REF. I INQUIRED FROM APCH AS TO OUR LOCATION ON THEIR RADAR AND I BELIEVE THEY INFORMED ME I WAS APPROX 5 MI OUTSIDE THE MARKER. AT THIS POINT THE GS BAR APPEARED ON MY HSI. I TOLD THE FO WE HAD ERRONEOUS DME READING. HE RETUNED THE VOR AND THE DME CHANGED TO AGREE WITH ATC'S CALLING OF OUR POS. ALL THIS TIME THE TURB HAD BEEN ANOTHER FACTOR TO ADD TO THE STRESS. SINCE THE GS WAS NOW IN EVIDENCE I ENGAGED THE ILS INTO THE AUTOPLT AND CONTINUED THE APCH COUPLED. AT APPROX 200 FT ABOVE THE FIELD I DISENGAGED THE AUTOPLT AND TOOK OVER MANUALLY (WE HAD BROKEN OUT AT AROUND 1500 FT). THE RPTED WINDS ON APCH HAD BEEN RPTED AT 210 TO 230 AT 21 KTS GUSTING TO 31-34 KTS. AT 200 FT TWR RPTED WIND OF 21 KTS FROM 210 DEG (A 70 DEG XWIND). THE ACFT WAS BUFFETING BUT I WAS ABLE TO DECRAB THE AIRPLANE; KEEP IT ON CENTERLINE WITH NO DIFFICULTY AND CONTINUE APCH. TOUCHDOWN WAS FIRM SINCE I DID NOT WISH TO TAKE A CHANCE ON AN INADVERTENT GUST. AS WE ROLLED DOWN RWY MY VERY ALERT SO CALLED OUT THAT THE AUTO THROTTLES HAD GONE TO GAR. I IMMEDIATELY DISENGAGED THE AUTOPLT AND PUT ACFT IN REVERSE. ROLLOUT TOOK CONCENTRATION AS BUFFETING FROM XWIND CAUSED CONTINUED INPUTS TO AILERON AND RUDDER TO MAINTAIN CENTERLINE. TURNOFF WAS MADE AT T-2 INTXN. MY FEELING IN WRITING THIS IS THERE IS A FREQ CLOSE TO ORD THAT THE VOR CAN LOCK ONTO INADVERTENTLY AT LEAST FOR THE DME AND PERHAPS THIS COULD BE CHKED. ALSO; QUICK REACTION BY SO ON LNDG POINTS UP EFFECTIVENESS OF CLR TRAINING AT OUR AIRLINE.