| Engine oil & filter | ILSAC GF-6A SAE 0W-20 (5W-20 only as a stopgap) · 7.7 qt (7.3 L) with filter, 7.4 qt without · drain plug 30 ft-lb (AMSOIL) | At purchase, then every 10,000 mi / 12 months. Every 5,000 mi / 6 months for off-road, towing or dusty use. | The filter and drain plug are underneath, behind the front skid plate. Reset the oil maintenance reminder afterwards.Oil filter, 2024 GX 550 · RockAuto ↗Oil drain plug gasket, 2024 GX 550 · RockAuto ↗ |
| Air filter | V35A-FTS element | Every 30,000 mi. Inspect more often off-road. | K&N's fitment listing says the 3.4 V6 takes two filters.Air filter, 2024 GX 550 · RockAuto ↗ |
| Cabin filter | Cabin air filter element | Every 30,000 mi | Cabin air filter, 2024 GX 550 · RockAuto ↗ |
| Spark plugs | DENSO EC22HPR-D7 iridium · gap 0.028 in (0.7 mm); don't adjust the gap | Every 40,000 mi (40k, 80k and 120k in the 2024 schedule) | Spark plugs, 2024 GX 550 · RockAuto ↗ |
| Engine & intercooler coolant | Toyota Super Long Life or equivalent non-silicate, non-amine, non-nitrite, non-borate HOAT coolant · engine 13.8 qt (16.1 qt with rear A/C), intercooler 3.9 qt | First at 100,000 mi / 120 months, then every 50,000 mi / 60 months | The schedule lists the engine and intercooler coolant together. Lexus says to have a dealer do the replacement.Coolant, 2024 GX 550 · RockAuto ↗ |
| Automatic transmission (10-speed) | Toyota Genuine ATF WS · 11.73 qt total (reference); AMSOIL lists 5.4 qt as the initial fill | Every 60,000 mi if you tow, carry heavy loads or idle a lot | Lexus warns that any other fluid can cause noise, vibration or damage, and says to see a dealer for replacement.Transmission fluid, 2024 GX 550 · RockAuto ↗Transmission filter, 2024 GX 550 · RockAuto ↗ |
| Transfer case | Toyota Genuine Transfer Gear Oil LF, SAE 75W · 1.88 qt | Every 30,000 mi off-road or towing | Gear oil, 2024 GX 550 · RockAuto ↗ |
| Front & rear differentials | Toyota Genuine Differential Gear Oil LT 75W-85 GL-5 · front 1.23 qt · rear 7.22 qt, or 6.87 qt with the rear locker | Every 15,000 mi if you tow | Overtrail trucks with the rear locker take slightly less oil in the rear.Gear oil, 2024 GX 550 · RockAuto ↗ |
| Brake fluid | DOT 3 (SAE J1703) or DOT 4 (SAE J1704) | Every 30,000 mi (2024 schedule) | The manual's pad wear limit is 0.04 in (1 mm).Brake fluid, 2024 GX 550 · RockAuto ↗ |
| Vacuum pump vane & caps | Vacuum pump vane and vane caps | Replace at 120,000 mi (2024 schedule) | This is a GX 550-specific schedule item. The guide says never to reuse the old caps.Vacuum pump vane kit (dealer) · Lexus Genuine Parts ↗ |
| Propeller shaft grease | Lithium chassis grease NLGI No. 2 | At purchase, then within 24 hours of any water crossing | The schedule also calls for tightening the propeller shaft bolts if you tow.Red-i hi-temp and moly grease kit (6 tubes) · CruiserTeq ↗ |
| 12V battery | LN4 case · at least 80 Ah (20-hour rate) and 689 CCA | Test at purchase | After a battery swap, re-initialize the power back door (and the moonroof and running boards if fitted).Battery, 2024 GX 550 · RockAuto ↗ |
| Tires & rotation | Overtrail 265/70R18 at 35 psi; 20s and 22s at 33 psi · wheel nuts 97 ft-lb | Rotate every 5,000 mi (2024 schedule), then register wheel positions | Check the spare too. It hangs under the rear on a chain.Digital tire pressure gauge · Amazon ↗ |