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No offense taken. I found it hard to believe as well and I was looking at it!
They say you can also run it up to 12000 miles between changes.
They've been around for years and they also make gear oil, transmission fluid and a coolant additive. Here's a couple of links that may explain it better.>>>>>>>>>>
Underdog,
thanks for all the info on Royal Purple. I'll check out those web links you supplied. Some other questions though. What does Royal Purple cost per quart, if you happen to know, and is it okay to switch to a full synthetic oil in these Explorer Engines? Mine is the 2005 4.0L. I did my own oil change 2 months ago and I used Castrol High Mileage Partial Synthetic Oil, because thats what came up for my vehicle on the computer at Advance Auto Parts and I figured it is a better quality of oil than a standard type oil. I saw the computer screen myself after the parts guy typed in my year, make and engine size. The Haynes manual only mentions standard SAE oil for my vehicle. I doubt the 2 owners of my vehicle before me used a full synthetic oil because the first owner leased my truck for 3 years, not going to sink money into it as a lease vehicle and the 2nd owner couldn't afford the truck and it was repo'd from him less than a year after he bought it. 12,000 miles between oil changes would be about 2 or 2 1/2 years of driving for me, but I would need an oil filter to hold up that long, less I just changed the filter more often than the oil. If I used Royal Purple, I'd probably change the oil every 5,000 miles. Thanks again for the info.
No trouble. I'm also running it in a 2005 4.0L and I'm the second owner. It's been running on dino oil for 5 years and 69K miles. Before I had it, it was a fleet vehicle in Utah. I'm sure it was abused in the 10K it was driven before me!
The RP 5W30 runs about $8 a quart. For the added benefits, it's worth it to me.
The filters are only available online for some reason. I will be ordering mine from Summit Racing. In the meantime I'm using the Moblie1 filter.
I think their FAQ can answer your other concerns
http://www.royalpurple.com/rp-faqs.html
Still, don't take my or anyone's word for it. Do your research. You may find a product you like better than RP.