What's in Havoline Synthetic

[Ramblin Fever]

to allow the pour point of the 5w-40 to be -51C or -60F?

Versus the 5w-30 synthetic's pour point of -36C/-33F

I thought this oil, 5w-40, was just a basic group III - is it not?

Another question, when people say that a synthetic oil will help point out your weak gaskets/seals, does that generally include a headgasket?

Basically, will a group III oil, increase the likely-hood of a failing headgasket (on an older engine) versus regular Dino? I've been wanting to ask this question for a long time.

I don't drive a vehicle/engine known for headgasket issues, it's just a curiousity question in regards to gasket's in general.

 

[Triple_Se7en]

Better write or call Chevron on that one. There's no VOA listed on the 5W-40 here. Actually... I never seen it in stores either.

 

[Drew99GT]

Head gasket failure won't be affected by using this oil.

 

[T-Keith]

No head gaskets are not made of rubber, they will not be effected by an oil. Even rubber gaskets and seals should not be effected by a modern synthetic oil.

-T

 

[wlkjr1951]

Years ago I read in a motorcycle magazine that synthetic would make older bikes and cars leak oil around the gaskets. Don't know if there's any truth to that but one of my friends who drives a mail Jeep told me after he started using one of the more popular synthetics that he noticed some oil leaks.

 

[Ray H]

While it's true that isomerized Group III and polymerized Group IV synthetic base oils are known to seep around elastomeric materials such as main bearing seals, valve cover gaskets, and oil pan gaskets from seal shrinkage, the situation is counteracted with certain lubricant esters which will also swell those seals. Head gaskets are composite metal/inorganic construction. They're not subject to oil chemistry problems or solutions.

 

[mechtech]

Many headgaskets have areas with 'rubber' type seals [for coolant or oil].
They sure CAN leak!