Mrgclaytrd

High guys I am new to this Forum and yes I have a 2001 GMC Yukon Denali and just turned over 340k today. I have the 6.0 Liter engine. Full time 4WD. we have been very blessed with not major mechanical issues. I bought in 2006 with 75K on it. Rebuilt front diff at 150K and put in Timken geears and bearings One waterpump, one gas pump. And get this you will not believe. Just for some reason me and my mechanic never changed spark plugs. Realized it at 300K when we flushing the rear differentail and putting in new fluid as we had never done that either. Amazing original AC delco spark plugs. I get right at 20 mpg if I drive 66 mph. so again very blessed and fortunate. Question: anyone runnning Penzoil Platimum High Mileage Full Syn in their 6.o Liter? Anyway good to be on here and looking forward to any help to try to reach 500K. Tks...Keep it rolling!