It seems like the guys using the Amsoil 5W30 are very pleased and convinced they have the best oil - at least within Amsoil's line of products.
Don't assume that because Amsoil PCO 15W40 doesn't offer as good of wear protection as the 5W30 that ALL 15W40's are similar.
I'd match Royal Purple 15W40 up against anything you could offer..... hee hee.
I've run the RP 15W40 in as low as -20 to -25 F condition in Wisconsin. I have industrial distributors in Idaho and Colorado who have Cummins, one with +200,000 on RP 15W40 the other with 275,000+. Industrial distributors in Texas that run a half a dozen as work trucks that always get 300,000+ before they trade them in.
We lubricate Caterpillar 399 (16 cylinder) diesel gen sets for drilling rigs in South America that are currently at a plus 18,000 hour drain interval where previously they had changed every 1000 hours. Fuel consumption, oil consumption, and wear are better. Literally 5% fuel savings and almost half the oil consumption. Projected oil life is now 26,000 hours.
I personally have run RP's 15W40 in my two Cummins and accumualted plus 225,000 miles trouble free with a 12,000 drain interval on standard Fleetguard Filters.
I have Hotshot drivers using RP 15W40 running 30,000 between oil changes. It has gone into older trucks that would consume Delo 400 or Rotella T at a quart every 3000 and now the truck does not use a quart in a 12,000 drain interval using standard oil filters.
It's good stuff.
By the way, Amsoil is a good company, but I wonder about the leading edge stuff. It is not the only company out there making good oils. This is where people like MGM and others tend to rub people the wrong way. Amsoil's a good product but it is not the only quality product that is available for use in a Cummins. It is not a panacea of all products.
Royal Purple, LE, Schaeffer, Redline, Delvac 1, Cummins Premium Blue 2000, Konklin, Hydrotex, etc. all make quality products.
When Amsoil part timers try to defend every comment made it really becomes quite trying at times. It drove me from wanting to become a bigger part of the TDR. Hell, even our editor bought into it. I try to offer technical reasons to use a higher performing oil and then offer alternatives to the enduser. I'm confident that if someone checks out what we have to offer, I'll capture alot of those sales. If it ends up going to a 'competitor' then so be it. The ENDUSER should make that choice based on his decision making not because Joe, Dick and Harry (who all happen to be selling a product) chime in on this list extolling how great the product is. This is like letting the fox have the run of the hen house.
By the way, MGM, although AMsoil is "a cutting edge company" it is not the only one. Royal Purple has had a 10W30 Diesel engine oil for winter use since 1992. (It is currently API Licensed CH-4 /SJ). We have also made special 'Polar Grade' engine oils for american drilling companies operating in Siberia that had the ability to restart at -80 F. But there's no reason to have that type of oil here in the states. I can not think of many places in the continental US that have more than a few days that are sub -20 ambient. (Wind chill has no effect on oils... . wind chill is the evaporation of water from exposed skin, only ambient temperatures effect oils) Granted Wind chills may have more effect on cooling systems or fuel systems but not the fluidity of the engine oil.
For those interested, Royal Purple has a website,
www.royalpurple.com.
We sell through three channels, Industrial, Retail and Racing, and a Trucking Division called Longrider.
To keep things non commercial, I will gladly answer emails at nitz@wt.net for those with direct questions.
Redram
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