10W40 For Summer

[PimTac]

Originally Posted by OilUzer
In old days everyone used 10Wx40. I used it in very cold places ... also junkyards had less cars than now

They used it because it was the standard until they discovered that it was not all it was cut up to be. Thevold 10w40 oils were not the best.

 

[y_p_w]

Originally Posted by PimTac
Originally Posted by OilUzer
In old days everyone used 10Wx40. I used it in very cold places ... also junkyards had less cars than now

They used it because it was the standard until they discovered that it was not all it was cut up to be. Thevold 10w40 oils were not the best.

However, the "basic" 10W-40 sold today at the same price point as 5W-20, 5W-30, or 10W-30 is probably going to be much better than it was 35 years ago when it was a common manufacturer's recommendation. A modern one is probably not bad. For a 30 year old car that specified it, it might even be ideal for an older car. But no manufacturer is going to specify it now as a standard engine oil for the US or Canada because it's going to result in worse fuel economy.

 

[dblshock]

my recent purchase of Citgo Supergard SN 10W40 motor oil lists Nitrogen as an additive..that new?

NITROGEN

 

[y_p_w]

Originally Posted by dblshock
my recent purchase of Citgo Supergard SN 10W40 motor oil lists Nitrogen as an additive..that new?

NITROGEN

Probably some sort of amine.

https://patents.google.com/patent/US20050181959

Kind of reminds me of Shell and their "Nitrogen Enriched" fuel additive. They make it sound like fertilizer.

 

[dblshock]

Originally Posted by y_p_w
Originally Posted by dblshock
my recent purchase of Citgo Supergard SN 10W40 motor oil lists Nitrogen as an additive..that new?

NITROGEN

Probably some sort of amine.

https://patents.google.com/patent/US20050181959

Kind of reminds me of Shell and their "Nitrogen Enriched" fuel additive. They make it sound like fertilizer.



...and just look at that Sulfur, it's beaming.

 

[shiny]

Thicker doesn't automatically translate into more protection. A thinner grade will flow faster than a thicker grade. Under extreme heat, a faster flowing oil stays cooler and cools your engine better than a slower flowing, thicker oil. Precisely how much cooling difference there is between 20 and 30, and between 30 and 40 is for smarter minds than mine to say.

But I can vouch for Kendall's full synthetic in 10w30. It holds up really well in the terrible Phoenix summer heat. My 92 mile work commute is very consistent. It's mostly highway miles with low traffic, few lights, the same route every day. The car sees little use outside of this commute. Keeping my tires properly inflated and the air filter clean, I've calculated my mileage with every weekly fillup for four years. Kendall consistently gets me 4-5% better fuel economy than did Napa and Pennzoil synthetics. The oil was the only variable that changed.

 

[BLND1]

Why not go with a thicker euro 5w-30?

 

[gfh77665]

Originally Posted by doolah02
I was thinking of using a 10W40 oil this summer in a 2001 4.0 SOHC engine. I'm in South Florida and I thought
the heavier oil would be ok for the summer months.



Definitely YES.

 

[RooflessVW]

I don't see a problem - have conventional 10W-40 in my car right now.

 

[wtd]

I run 10W-40 in my 98 chevy K3500 with the 454 in it and in my 70 Monte Carlo with a 396 big block. It works fine but is a little slower to crank during the colder weather.