1979 MGB oil change interval

The MG’s were built to lower tolerances and lower performance than modern engines so there’s little benefit to the synthetics and I agree with sgtrock that pretty much any 10/30 would be fine. As far as additives go, if it makes you feel better, you can pick up a ZDDP additive at Moss Motors.
But because of the low usage, much more important is the frequency of the oil changes, which if you’re driving year round would be about every 6 months and would include greasing and lubing everything.
However, if your year still has brass transmission and drive train components, it’s very important to use the correct “old spec” gear oil to avoid degrading the syncronizers and seals.

My current Brit Car is a 1952 MG TD that I’ve had for over 30 years and from my experience the best thing you can do for your car is to drive it frequently to get the oil distributed, boil the moisture out and get the coolant and gas flowing. Still runs like a top.

There is a principle called microfiltration. The wear rate is proportional to the square of the mean particle size in the oil circulating. I have been inserting ceramic magnets in the clean side of my oil filters. They take out all the magnetic particles that are too fine for the filter to catch. this reduces the wear rate in the engine, the friction in the engine increasing fuel economy by up to around 5% and increases the life of the oil and filter-essentially doubles the life of lil and filter. The one I use is shown on a web site. They are about 1/4 inch square in cross section and about 1 inch long. They grab onto the steel tube on the inside of the filter media. Clean off and install in the new filter at oil change time. I have been using exclusively synthetic oils in all my cars for over 40 years and magnets in oil filters for about 10 years. My newest car is a BMW 7 1994, then a 82 Nissan diesel and a 72 SS ElCamino. More years per car.

The last time I had an engine failure was in a 56 Desoto and It failed with the speedometer needle pegged at the limit of it.s travel.

Rust kill our cars so there would be no benefit to me except the extra fuel mileage which I am very skeptical of.

If manufacturers could get 5% greater mileage by incorporating a 1" long magnet in the oil system, every car would have one.

Okay you may disbelieve physics if you choose to; it is your choice.

That is what the hucksters who were peddling cold fusion said, and throwing around a lot of scientific sounding terms does not make you a physicist.


Okay key principle is microfiltration wear reduction in lubrication systems. Use it or don’t as you like; results are as you choose.

The claim of 5% better mileage is the problem. Car companies would spend many millions to achieve that, including adding a magnet, if it worked. What’s your proof?


That may be your only fact based statement. If I put magnets in my oil filter I can claim all kinds of imaginary results.

Your peer reviewed sources proving your “science” and the magnets efficiency thereof?

I’m to cheap to use real magnets so I use imaginary magnets to get my imaginary results.