Originally Posted By: justinf89
Well id like to stick to AMSOIL but even they say to change it yearly. If that's not the case then ill stick with them.
Now the question is why don't they recommend their newer 5w-40 cj-4 in my truck? They recommend the older 15w40 first. I assumed it had to do with ulsd but that's what everybody is using now anyway. Any thoughts?
Amsoil has the " ... or one year ..." OCI mentality for the very same reason that all the other lube and equipment OEMs do. They are protecting themselves via warranty concerns.
Lubes have ZERO idea how old they are. It is very true to say that lubes will be usurped by each upcoming generation, and that if a lube approaches 5 years old, I'd be leary of it, whether in the bottle or the crankcase.
But for any other situation, if you are interested in extended OCIs, there is reasonable evidence to show that any quality HDEO can surpass 365 days EASILY. Two and three years are not unheard of; there are used oil analysis out there to show it's VERY viable, in certain situations. I personally am into my second year on 10w30 HDEO in my Kubota tractor and Kawasaki-powered Scag mower, and into my 3rd year in the 1966 Mustang 289 V-8. Now, this is predicated upon a healthy operating system; no coolant leaks, no air filter leaks, no fuel leaks, etc. And when extending the OCI, used oil analysis are a very practical tool. However, many people find that you can OCI for as cheap as you can extend and UOA, if you annual mileage is low.
It's all about choice, and balancing your needs with your wants, and finding your personal comfort level. Some people sleep soundly running synthetics with bypass filtration with 5k miles OCIs; I could not do that. Others cannot see the sense in extended OCIs.
The Dmax engine is quite possibly one of the best wearing engines of all light duty diesels on the market; they simply turn in stellar results in a very predictable fassion, if all the operating systems are in order. The lube choice matters little; all brands have shown great success in a Dmax.
If you're going to use Amsoil, I'd extend the OCI and do used oil analysis; the product is quite capable. Get a Fumoto valve and make sampling easy.
If you're not going extend the OCI, use a quality dino HDEO and OCI by the OEM/OLM recommendations.
If you read my signature line, I comment on the practical and logical approach. Review your operating parameters and conditions, determine your maintenance plan, then pick a lube that compliments the program. Trying to "justify" a lube choice by manipulating the other conditions will only lead to waste or risk.
