The recommended oil type for a 2004 Lexus GS 300 is 10 W 30. The oil capacity for the car is approximately 5.7 quarts.
5w30
5W-30 Synthetic Oil.
Bottom of the engine on the oil pan.
Every 5k with conventional oil. Every 10k with synthetic oil.
It takes 5w30 and 6 quarts.
s.b. at the top of the cam cover, will have an elec. lead to it.
10 qtz
4.5L
5.0 QUARTS
It is 6.7 quarts for the 2.5L
5.7 qts with filter, look in your manual. I was shocked to find this out and made sure the mechanic I use was aware, he went to LEXUS web site and found same answer.