1997 Buick LeSabre Owner's Manual - Page 264

Automatic Transaxle Fluid ~~ ~ ~~~~ When to Check and Change A good time tocheck your automatic transaxle fluid level is when the engineoil is changed. Change both the fluid and filter every 50,000 miles (83 000 km) if the vehicle is mainly driven under one or more of these conditions: 0 Operating the engine with the air cleanercan off cause you or others tobe burned. The air cleaner not only cleans the air, it stops flame engine if the backfires. If it isn't there, and the engine backfires, you could be burned. Don't drive with it off, and be careful working on the engine with the air cleaner off. In heavy city traffic where the outside temperature regularly reaches 90 "F (32"C) orhigher. In hilly or mountainous terrain. When doing frequent trailer towing. Uses such as found in taxi, police or delivery service. 0 0 NOTICE: If the air cleaner off, a backfire can cause is a damaging engine fire. And, dirt can easily get into your engine, which damage it. Always will have the air cleaner in place when you're driving. 0 If you do not use your vehicle under any of these conditions, the fluid and filter do not require changing. See "Scheduled Maintenance Services" in the Index. 6-16