Originally Posted By: Garak
Originally Posted By: fdcg27
I hate to be pedantic, but you are using 10w30 in one of the vehicles in your sig. Could 10w30 actually offer some advantage over 5w30 in a specific application, and are those advantages as relevant today as they were in 1985?
That was on a special I couldn't pass up, and they were out of 5w30. There's certainly not anything inherently wrong with the grade. I've used it for many years in fleet usage. It's just that 5w30s have improved. And a 10w30 being rather obsolete doesn't mean it's useless or flatly inappropriate.
As for potential benefits, of course it's possible. However, 5w30s are far more shear resistant than they used to be, and that's one of the reasons the 10w30s were favoured years back. In my fleet usage, I could have probably gotten away with straight 30, given the lack of cold starts.
One potential benefit may be if someone is looking for something with higher ZDDP in a 30 weight, and goes for a 10w30 HDEO. That would be useful in my old truck.
With respect to the original poster's question, I'd say it's "fine" but not "optimal." My old Audi speced 10w30 way low, and so does the old F-150. Given the oils of the time, they made the best recommendations they could. So, if I find it on special again and nothing else is available, I'd use it. I wouldn't go out of my way to find it. What's in the F-150 is my last jug, by the way.
Originally Posted By: gfh77665
My point was not about Thick vs. Thin, but how rationale is so inconstantly applied. Some think Chrysler calling for only 10-30 is stupid, while they would praise and gush about Ford for their 5-20. Peoples minds aren't open viscosity wise.
Well, speaking of rationales, we do know what the rationale is for a 5w-20. There are CAFE requirements and indications they can protect just as well as a 30 weight.
We don't know the rationale for the 10w30, and that's the problem.
That being said, I'd stick to what was recommended in the manual. I think it's a strange choice by the manufacturer, but they provide warranty coverage, not me.
I believe the rationale was that in SF and SG days oil used to not be as good, and 10w30 would hold up better than 5w30. Now those days age gone, sure.. but are we talking about the 80s? My folks liked 10W-40 because of the quality of the oil back then. Used it in winter too
I am unsure why the "0" W number is not sought, followed promptly by the "5" number nowadays. 0W-30, 0W-40 etc. I know HTHS makes some cars "HAVE" to have a 5w30.. even then, i wonder what would happen if a 0w30 went in.
CATERHAM? What can happen if an oil has a lower HTHS than a manufacturer specifies? (Dare i say it.. "too thin?" Im thinking of 0w30 Redline where 5w30 Redline is what people use, specifically. On the non-10W-60 spec'd engine.)
