The E-Type (XK-E) Forum

What is the consensus on engine oil for a 94,000 mile V12 that appears to be healthy internally? (Good compression, good oil pressure, runs well).

I believe the book calls for 20w50, but I’m open for suggestions.

The car resides in Florida, so it rarely sees any weather below 40 degrees.

Synthetics?
ZDDP?
Viscosity?

Thanks

Hi . I have 1973 E that I bought new, and thw best oil, I have found, Is straight 30 weight.. Non syn, non detergent. Good oil presure, never leaks. Walmart is the best deal.

John

To my way of thinking, our older cars with flat tappets need an oil with adequate ZDDP to keep us from running the cams flat.

Sadly, as oil formulations changed from API SL to whatever the current standard is, ZDDP has been steadily reduced to protect the catalyst from Zn or P poisoning. This reduction was accompanied by a move by the automakers from flat tappets to roller tappets that do not require the high ZDDP levels.

I personally look for an oil with around 1200 ppm Zn and P. My expert mechanic tells me that I want 20W-50. While there are many boutique oils out there, I run Valvoline VR-1 and change it every 5,000 miles.

Use any brand 30wt year round. Change every 3000 miles. Don't use synthetic. Every 2nd change, send sample of old oil to be analyzed. John 1973 E Type original owner

Hi.

Everyone is free to do what they think is best.

Reviewing my factory manual, they call for 20W-50 changed every 3,000 miles. Filters changed every 6,000
Miles.

I know some advocate frequent oil testing. The cost to me is such that I do not see the cost benefit.

I change my oils on my cars every 5,000 miles. My thinking is that the heat stability has vastly improved since 1971

As I like to say, your car, your money, your choice.

Yeah, I try to take advantage of modern technology and use a modern 20w-50. I change it once yearly, since waiting for 3000 miles would be years and years and I'd be concerned with the acids that form in the crankcase due to condensation from such minimal use. I drive my cars at least 20 miles weekly, but that's still not very much.

I've sent the oil out for testing since I just bought the car a few months ago. After that, I won't unless I have some reason to. When I had an airplane, we did oil analysis every oil change, but that was for other, obvious reasons.

On modern cars, I have never had an issue going 7500 miles on an oil change. I'm convinced that modern synthetic oils and filters can far exceed that.

Totally agree. I tend to drive my classics 3-5000 miles annually so my interval about yearly. As you state mostly to remove contaminants as I am sure the oil is pretty much unchanged.