Saturn 1.9 sohc oil viscosity vs mpg
 

It's coming up onto time to do a service on the poor Saturn

I am wondering if there is the potential for some low hanging mpg fruit to go down to a 5/20 full synthetic over the 5/30 conventional I'm sure is in the car.

I plan to also service the manual trans was well.

Thoughts

No idea but apparently some tests show 1-3 percent improvement in mpg. Saw this at the store too versus regular synthetic

Know the Saturn's requirements. are they finicky?

www.yourmechanic.com/article/a-guide-to-motor-oil-additives_2

They have a propensity to use oil profusely due to insufficient oil drain back holes in the pistons oil control ring groove. Mine is so so in that's respect.

So let's not act like the manufacturer actually had everything completely figured out in this case.

Plus it's a $600 car so....eh

I'd at least drop down to a 0w. Best I can tell, it's superior to a 5wXX in every respect. I've known a few engines to burn a bit of oil when cold when dropping to a lower winter weight, but everything I know about oil tells me it should be doing a better job of protecting the engine, in addition to improving economy.

I would think that as the engine has aged, tolerances have increased not decreased? Also, full synthetic is downright cheap if you know where to buy. I get mine at Costco, $30 for (2) 5 quart jugs.

https://www.dragzine.com/news/what-i...l-viscosities/