Mobil One vs Royal Purple

Internal combustion engines of today can routinely give 200,000 plus miles of trouble free service. Many of us remember when reaching 100,000 miles was a rare accomplishment, so don't confuse a high mileage engine (compared to historical mileages) with using some "miracle" oil that dramatically reduced or eliminated wear.

Reading your owner's manual and using any oil, changed at correct intervals, that is recommended for your engine will provide you with economical long term, high mileage service from your engine.

I've been running Royal Purple in my Harley for the past 10 years and never a problem. I use 20W-50 for crankcase and primary chain case, and 75-150 for transmission. When I change the fluids, they are clean...unlike other brands I tried before. No metal flecks, little carbon buildup and still smells like it came out of a new bottle. The engine temp runs cooler overall and gas mileage increased about 2-5mpg. I've never used it in my MH but am considering changing from Mobile 1.

Never used Royal Purple in a MH but used it for years in my cars. Never a problem. But then again, in 45 years of driving, I've never had a oil related problem. I did have a lack of oil problem, but that's a different story.

I would make sure the oil filter has so called "one way" check valve or every start will be like a cold start. Should say on box or in info somewhere. It keeps (all or most) of oil from dripping back down and then no oil in top end when you start up.

Been using full synthetic Mobile 1 on my Ford truck since it was new 9 years ago at 7k intervals. 160k miles later and still runs like it's brand new. I use the same product on my previous MH which had 60k miles when I sold it as well as the current one and never an issue. I do use royal purple on the genset because it only takes 1.5 quarts. I have full confidence in Mobile 1 and there is no way I would spend that kind of money to use royal purple in the engine. I think royal purple is great oil but way too expensive to do anything but the gen on my budget. And really I don't see the need. I don't think I have ever read of a Ford engine failure due to Mobile 1, or any oil for that matter. I am sure it happens but it has to be pretty rare and an anomaly.

That's what I spend...my 7.3 holds 15 quarts....

NINETY BUCKS for an oil & filter ? C'mon...........

Was thinking of switching over to royal purple on suvs but decided to stick with mobile 1 + filter. On the diesel i use rotella T5 and mobile 1 filter. Only way to find out the results of which is better and last longer is send it to the lab like kayteg1 mentioned.

Blackstone Lab charged $25 for oil test and they send you free containers for samples.
Internet is full of it and screening any review usually takes more time than do your own testing.
I did not like Mobil 1 for generating iron and in diesels used Rotella T6.
Now having gasoline engine in Mercedes still did not want to use M1 and bought approved Castrol
Will send sample of Castrol for test once I exceed 10,000 miles on it