TreeHey Rick, I use NGK BKR6E-11 (copper) and replace every 6 months ~ $24 a set of 4 on eBay
mister2The OEM part number for Red Top spark plugs is toyota 90919-01179, so any equivalent to those will do the job Rick. For NGK, it would actually be NGK BKR6EP11, which are platinum tipped.