Oil brand change guidance

Effectivity: Global 7500 aircraft 

ATA 79  

By: John Balabanian –  Global 7500 Customer Services

We would like operators to be aware of the steps that should be taken when they choose to change approved oil brands on their aircraft. 

A change over from one approved oil brand to another of the same type may be accomplished by adding the new oil at the time of servicing (topping off) in the engine reservoir. The topping off method is consistent with the auxiliary power unit (APU) oil servicing as well.  

 Additional guidance can be obtained in GE Passport Service Bulletin (79-00-0001-00A-930A-D-001- OIL - General (79-00-00) - Approved oils). 

It should be noted that during the oil changeover process, the oil in the Oil Replenishment System (ORS) should be replaced in its entirety with the new oil brand and the ORS tank probe should be re-adjusted per the Aircraft Maintenance Procedure (AMP) (BD700-A-J79-31-03-00AAA-271A-A- Airframe-mounted oil-tank probe - Adjust). This procedure should be carried out to ensure that the oil level in the ORS tank is reading correctly.