“Here is the list and recommendation for the spark plug replacement that list in the Owner's Manual and Repair Manual for Lexus models and years.
ES300:
1990-1998 60,000 miles
1999 90,000 miles
2000 to date 120,000 miles
IS300: 2001 to date 120,000 miles
RX300: 1999 to date 90,000 miles
SC400/430:
1992-1998 60,000 miles
1999 90,000 miles
2000 to date 120,000 miles
GS300/SC300:
1993-2000 60,000 miles
2001 to date 120,000 miles
GS400/430:
1998 60,000 miles
1999 90,000 miles
2000 to date 120,000 miles
LS400/430:
1990-1998 60,000 miles
1999 90,000 miles
2000 to date 120,000 miles
LX470:
1998 60,000 miles
1999 90,000 miles
2000 to date 120,000 miles
LX450: 1996-1997 30,000 miles
I hope this will help some of you to make the decision on your services. We have a lot of discussion about this issue before and how the Lexus dealer charge you for certain services. This is just a guide line that Lexus recommended in the owner's manual, not madatory or anything.”

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