Amsoil OE ??

[Copperhead]

Don't overthink it. If 5w50 is spec'd, then go with it. Use the 10w30 where it is spec'd. If you are getting great results with that, then no use messing with a good thing!

 

[RUSSELL SHETTLE]

Don't overthink it. If 5w50 is spec'd, then go with it. Use the 10w30 where it is spec'd. If you are getting great results with that, then no use messing with a good thing!

I can only agree because the amount of choices in oil from Amsoil is mind boggling. Fortunately, there is on only one 5w50 to chose from in their lineup and it's SN rated of course with a 12.5 TBN. Good oil for sure and since that viscosity is the latest spec recommended by Tuff Torq I intend to stay with it and yes I'm getting great results. Of course that may not be fully realized for quite some time and I am starting out with a new system, not one that failed and became rebuilt.

What's curious to me are the specific reasons why Tuff Torq is recommending the higher viscosity range, 10w30 to the 5w50. Surely, just changing from conventional 30 to a synthetic 30 would have been enough of a recommended longevity and performance improvement. When I asked the rep from Tuff Torq about the viscosity change I didn't get much of an answer. Only that the recommendation came out a few years ago. He sounded busy so I didn't push the question any further.

Do I care? not really, just interested. I would just like to know from a engineering standpoint.

 

[Copperhead]

A lot would have to revolve around the hydrodynamic lubrication performance of a 50w oil over a 30w in their particular gear sets. Evidently they have worked it out in R&D, and based on the components in their drives, they feel the 50w is a better performer. Conventional or synthetic, the molecular size is the same. How it holds up under stress over time, a synthetic will hold up better.

 

[WilliamBos]

Here is an interesting bit on Citgo's take on Dexos.

http://www.citgo.com/WebOther/EMail/newsFlash101001GF-5.pdf

 

[Copperhead]

Thing is, there is a Technical Service Bulletin out from GM where they do allow a ILSAC GF-5 spec oil to be substituted for a dexos1 variety. They say only if you can't get a dexos1 spec oil, but the implication with this TSB is that they know GF-5 will do the job just fine.

I don't worry about it. Neither my previous 2013 1500 5.3 or my current 2015 2500 6.0 have gotten an "approved" dexos1 spec oil. The oil I use meets the API SN, ILSAC GF-5 specs and they claim dexos1 compliance. Good enough for me. I really think that the only real reason that GM pushes the dexos1 spec is so that folks will pay better attention to what they are putting in their motor. They want to make sure that most folks are not putting some rot gut oil made from dog snot in there. If they push the dexos1 spec, then folks will be putting in better quality oils.

 

[WilliamBos]

Thing is, there is a Technical Service Bulletin out from GM where they do allow a ILSAC GF-5 spec oil to be substituted for a dexos1 variety. They say only if you can't get a dexos1 spec oil, but the implication with this TSB is that they know GF-5 will do the job just fine.

I don't worry about it. Neither my previous 2013 1500 5.3 or my current 2015 2500 6.0 have gotten an "approved" dexos1 spec oil. The oil I use meets the API SN, ILSAC GF-5 specs and they claim dexos1 compliance. Good enough for me. I really think that the only real reason that GM pushes the dexos1 spec is so that folks will pay better attention to what they are putting in their motor. They want to make sure that most folks are not putting some rot gut oil made from dog snot in there. If they push the dexos1 spec, then folks will be putting in better quality oils.

After doing the research here and the other site, running a good synthetic that meets those specs should be good enough.

People will argue about Amsoil, but when it is priced lower than mainstream brands, I am gonna give it a look.

The brand you run is hard to come by up here, or I'd run it.

Ive never run the bargain basement .99/l oil, the thought scared me.

Now, how much does the VVT and the oiling system have to do with each other?

GM says no 40W in these engines, so no T6 5W40. Is the VVT the reason?

 

[Copperhead]

Could be. Engine clearance tolerances are so much tighter nowadays. Even the heavy truck diesel OEM's are factory filling and recommending 30w oils now, clear up thru 15L engines.

The so-called bargain basement oils compare well with name brand oils. Some might even surprise you! Take a look at oil comparisons done by The Petroleum Quality Institute of America

 

[kenmac]

Oil formulations are changed all the time.. A tech at cat told me they will perform UOA'S on equipment ,and have their oil formulation changed to meet their needs

 

[Copperhead]

Wow. A unique motor oil formulation for individual applications! That has to be a wallet buster. I could see maybe changing brands and using that unique formulation that is characteristic of that brand. That is the way I go with my oil choices for my heavy commercial use. I sample and see what the particular motor seems to do the best on and change to a different brand depending on the results. While all modern motor oils are great, each engine seems to have preferences for what works best with it. One motor I had, did quite well on Kendall 15w40 conventional. Over 1.4 million miles without a major repair or rebuild. The next one, did really well on Mystic 15w40 synthetic blend. Almost 1 million miles before selling it. My current one is really performing well on a Schaeffer 15w40 synthetic blend. This current motor totally brutalized a Chevron Delo in both 15w40 conventional and 5w40 synthetic varieties. But Delo is a very good oil. Just not in this motor. Rotella in any of them was about average. Nothing great, nothing bad. But that takes nothing away from Rotella. In many applications, it does a great job. There just isn't one all perfect brand or product that is heads and shoulders above everyone else in every application. When you find something that delivers the results you are looking for, stick with it.