What was found
ATB - IAS DISAGREE AND ALT DISAGREE EICAS MESSAGE DURING CLIMB A/S DIFERRENCE OF 10KTS BETWEEN CAPT & F/O A/S INDICATORS ALTITUDE DIFFERENCE OF 300' WHILE PASSING 10,000'MSL COMPLETED AIRSPEED UNRELIABLE QRH PROCEDURE SELECTED L ADC.REPLACED CAPT'S AUX PITOT TUBE AS PER AMM34-11-01-401 & LH ADC AS PER AMM34-12-01-401. PERFORMED CAPT'S PITOT LEAK TEST AS PER AMM34-11-00-730-811. ALL INDICATION WITHIN LIMITS. NO LEAK NOTED. CAPT'S PITOT LINE CHECKS NORMAL.