Does a lighter moter oil give you more power?

bilrus61 · Mar 8, 2012

I guess this should be in the oil and lubricants section but here I post it. Recently got a new car and saw they reccomend 0w 20 oil for better mileage. I've heard of them going with light oil to make the mileage requirments. My question is on a diesel engine, such as my L5040 kubota, how much if any horsepower will I gain going from 15W 40 to say 10w30? Any idea out there? My manual says both are fine for the temps I use them at but has anyone actually pinned down the increase in power going to the lighter oil would bring? Is it one horsepower? One tenth of horsepower?

shortthrow50 · Mar 8, 2012

bilrus61 said:
I guess this should be in the oil and lubricants section but here I post it. Recently got a new car and saw they reccomend 0w 20 oil for better mileage. I've heard of them going with light oil to make the mileage requirments. My question is on a diesel engine, such as my L5040 kubota, how much if any horsepower will I gain going from 15W 40 to say 10w30? Any idea out there? My manual says both are fine for the temps I use them at but has anyone actually pinned down the increase in power going to the lighter oil would bring? Is it one horsepower? One tenth of horsepower?

theoretically yes. less drag but it is so minescule, its not even worth debating whether if a switch will yeild you any results. So many variations in factors. I have alot of experience with changing things out and getting vehicles dynoed. I can run the same setup on my mustang and have 5-10 hp differnces even at the same temperatures. Outside temperatures even a little change, will change the hp more so then a oil change. due to the fact that the air entering the engine.

MrWhippy · Mar 8, 2012

maybe, but you also run a risk of not having an adequate oil layer as engine temps go up.

Edit to add: As long as you're within the manufacturer's recommendation, this wouldn't be a problem. I wouldn't go thinner though.

Dr_Zinj · Mar 8, 2012

It's theoretically possible to get less hp with a lighter oil, especially with an older, more worn engine. A lighter oil can allow more blowby past the piston rings and down into the crank case, which is vented, costing you power. That's one of the reasons why people put heavier grade oil, or products like STP, in older engines.

Of course combustion products in your oil aren't good either.

jonyyuma · Mar 8, 2012

I personally don't believe you would notice a hp change in a tractor as large as yours.The lighter oil is for better mileage.I personally tested both our 180 hp 4 cylinder cars with5w20 oil in two configerations. both on conventional oil with proper same weight and then with synthetic oil same weight. Results one gained 1 mpg on Mobile1, it has a 5 speed auto. The other has 6 speed auto and on O-reileys SYN. oil it pick-up two mpg. On my tractor i use synthetic, because i run it WOT or 2400 rpm. I have no way to tell any additonal hp??I don't know enough about Zer-20w-oil to try it..

dodge man · Mar 8, 2012

If you want a lighter oil, switch to synthetic. It will be thinner when you start up, but also hold up to the higher temps. How much power increase, maybe 1 hp would be a guess on my part, maybe less. It would be enough that it might show up on a good dyno, but you wouldn't feel or notice the difference.

Ford tractor · Mar 8, 2012

Yes you can have more HP. Especially if you go to a thinner fully synthetic oil.

But don't expect any seat of the pants feel difference. It's more a statistically improvement that takes a pretty sensitive measuring tool like a dyno.

rsewill · Mar 8, 2012

Your wallet will be a bit lighter but otherwise you'll feel better with full synthetic. I use it in everything but I can afford the extra $50 a year.

bulldog69 · Mar 9, 2012

It's doubtful you will notice a difference in HP but I have noticed a difference in fuel consumption. My M9000 doing most tasks burns just over a gallon per hour. I use full synthetic 5w30.