1968 oil choice

[mbsf1970]

Memory failing me:

10/30 or 20/50?? I assume conventional. do I need to use high mileage oil?

My car experiences seemingly low oil pressure --according to gauge. Needle sits a fraction above left side marker of gauge...rarely gets too much to the right of that...

thanks,

Stephen

 

[franklinair]

The only way to be SURE is to connect a direct reading gauge in place of the electric sending unit. Then you'll know the true oil pressure. The sending units are not high tech calibrated units.
Then you'll know what the relative pointer position is in relation to oil pressure.

Neil

 

[slimt]

Memory failing me:

10/30 or 20/50?? I assume conventional. do I need to use high mileage oil?

My car experiences seemingly low oil pressure --according to gauge. Needle sits a fraction above left side marker of gauge...rarely gets too much to the right of that...

thanks,

Stephen

Im experiencing the same thing..

 

[rvrtrash]

As usual, Neil is right on. Ford gauges are not particularly accurate. The hash marks at either end are a "safe range" and only meant as a slightly more sporty version of an idiot light. It's why "back in the day", everyone installed aftermarket gauge packages.

As for oil viscosity, lower viscosity, i.e. 10-30, will give you a slightly lower reading than higher viscosity oils, i.e. 20-50, at start up and high rpm, but if the oil is too thick, you could actually do more damage by the oil not flowing as easily. In colder climates, say, maybe Alberta, Canada, you probably want to run the lower viscosity so you have easy flow at start up, especially in cold weather.

Again, putting a mechanical gauge on the engine while it's running is the only way to tell what your true oil pressure is.

Steve

 

[BigJim]

Stick with pure dino oil. Synthetic or synthetic blends can cause oil leaks in older engines.

Sent from my SM-G920P using Tapatalk

 

[robert campbell]

Stephen,
All the above is great advice. The addition of ZDDP for flat tappet cams (all stock 289, 302, and 390 engines) is a must these days. The oil companies have been under pressure to remove Zinc-dialkyl-dithiophosphate (ZDDP) due to pollution concerns. Lack of this compound in your oil will cause premature cam failure. The reason they can now remove this compound is almost all modern engines use roller cam technology and do not have flat tappet lifters.

https://www.amazon.com/ZDDPPlus-Eng...t_2?ie=UTF8&psc=1&refRID=4Q9DDKRYN4KPFE1017BJ

As most of our cars have were born and raised in the late 60's and the removal of ZDDP has been a slow process has not taken its toll yet. So most engines are still ok. Keep in mind most of our cars see sparse usage.

If I had a flat tappet cam these days, a bottle of ZDDP would be in every oil change. Both my cars are roller cams, but my truck with 250k miles gets it every time I change the oil. It is normally available at any auto parts store also.

Rob