Engine oil weight and fuel economy

[MetroMPG]

i'm not surprised about the google position - the whole reason i put that page together is because i couldn't find any block heater comparisons anywhere on the web. so now everyone is finding it. that page, and my page about winter mpg losses, are the 2 most search-engined pages on my site.

[jamescartagena]

I found this article on the SmartGas website by Louis LaPointe dated April 2005. I put in excerpts here but basically he found his mileage increased when he put a heavier weight oil in his vehicles. Anyone willing to try this? I'll try it in spring when I am due for my oil change.

While playing the Mileage Game all that time, we investigated many different oils, special fuel additives, floatless carburetors, special ignitions and various other techniques to improve mileage. To hell with horsepower. I was only interested in MPG. Very few things really did as people claimed or performed according to rumor. It proved tough to squeeze more MPG from a gallon of gasoline or diesel fuel. Many combinations dropped MPG. While horsepower was easy to come by, MPG was really difficult. Dozens of items could be bought to increase power in any car. But that was too easy. Better mileage was tough, except that nobody cared because gas was so cheap back them. People thought I was silly for doing what I did by continually testing fuels and oils. For instance in Alabama I once lost a camshaft in my 1949 Olds due to using a purple 10W-30 oil. An engine builder suggested I switch to straight 40-weight truck oil to prevent another flat cam. The McGurk camshaft worked just fine after that. But my mileage went up in that car after the switch to the thicker oil. That went against everything I believed at the time, so I studied the science of lubrication or Tribology as a result. In 1967, I found a job testing lubricants and soon learned the real facts about oils, not by rumor or hearsay but by actual testing and analysis. Today we make oil testers for which I own a patent. But hardly anyone cares to view the truth about oils. They prefer to believe ads that appear like mindless propaganda, offering zero data. They are the slaves of advertising.

We just purchased a 1995 Mazda stick-shift 2.3-liter pickup to complement the Neon for testing. We first found a baseline in its as-purchased shape of 13.4 MPG in the city. Then we used Torco motorcycle T-4M 20W-50 engine oil, Baldwin filters, acetone with additives listed below, a new FOG device, NGK V-power plugs, Torco 75W-140 gear lube and other changes like we do with all the cars we use for mileage testing. We expected to double the mileage figures--as we have with many other vehicles. On a first test drive up North on Shell gas, the MPG was just short of 24. Then we added a couple of quarts of 40-weight oil and a new Baldwin oil filter along with 6 ounces of acetone into a full tank of gasoline. What a difference that made. There is noticeably better pickup and smoother idling. The idle speed went up from 800 to 900 RPM. The acceleration above 60 MPH was quite poor at first, even at full throttle. But after just these three little changes, the Mazda pickup seems to have better pickup. The exhaust pipe used to be sooty and black. The exhaust pipe after a couple of days became brown and now is so clean, my finger does not pick up anything. I attribute that to the acetone mix.

[JanGeo]

You guys ever hear of an oil pressure gauge??

If the oil is too thin at any temperature then the oil pressure will drop. IF it is too thick then the bypass in the pump will kick in and you waste power pumping oil back into the oil pan instead of through the filter and engine. All you need to do is get an oil pressure gauge connected and you can tell when the oil is too thin or dead worn out by the pressure drop. The best test for worn out oil is between your fingers - if it is slippery it is still good.

As far as additives I have used teflon additives from Slick50 and ProMotion in all my cars after they are broken in properly and beat on them and abuse the oil (castrol regular and more recently syntec blend) and have not had any engine failures. I also put the slick50 gear lube in the tranny and that although takes a while to start working helps also. Any additive that requires constantly adding for each oil change is not what you want to be using as it ends up costing too much usually.

[jamescartagena]

Check the following website out I believe it is www.synlube.com. Although the sell their own "special oil" and have to push it on the website, they do have interesting reading on mineral and synthetic oils. Very detailed information on the different types of synthetics. Anyway very good reading.

[MetroMPG]

Originally Posted by JanGeo

You guys ever hear of an oil pressure gauge??

you know, i've never owned or even driven a car with an oil pressure gauge... no, i think maybe there was one in a vw cabrio i fixed up. but i guess i didn't look at it too much. i suppose that's why it never occurred to me it would tell me if my oil was too thin. i knew there must be a simple answer.

now a bunch of questions...

do you know if a gauge can be easily retrofitted? or can you just hook up something temporarily? would the gauge just go in the spot the existing pressure sending unit is (i think that's what it's called)? i assume the existing unit is just a binary device with a threshold for the idiot light.

i'm just being lazy, i'm sure i could look up this info on the web.

[SVOboy]

do you know if a gauge can be easily retrofitted? or can you just hook up something temporarily?

Yes yes. Auto stores sell crappy oil pressure gauges for 15 bucks in my neck of the woods, you just hook it up and you can take it right off if you want.

[JanGeo]

Yup the sending unit is a on off switch and get this - it turns on below 6-7 psi so by the time that idiot light comes on - you have probably cooked the motor! I don't know if the computer monitors it or not but it turns on at low pressure and is open at high pressure so if you disconnect it you should be ok. A oil pressure gauge can be mechanical with a small hose into the cockpit which sometimes takes a while to respond to pressure changes if the line is long and small in diameter restricting oil flow or electric with a variable sending unit which can fail and respond faster but not leak into the dashboard. The hole should be a standard pipe thread hole.

[krousdb]

Originally Posted by MetroMPG

nut job that i am, i went ahead and swapped out 1L of 5w30 syn for 1L of 0w20 syn from my car.

I have run 0W-20 Mobil 1 on the Prius for 62k miles, changing every 12 - 15k miles. No problems so far.

I have the same 0W-20 in the del Sol, both engine and tranny.
So far, so good.

Dan

[SVOboy]

I have run 0W-20 Mobil 1 on the Prius for 62k miles, changing every 12 - 15k miles. No problems so far.

I have the same 0W-20 in the del Sol, both engine and tranny.
So far, so good.

Dan

Can I buy it at autozone? I will do the same thing in a few miles time.

What filters do you use?

[MetroMPG]

Originally Posted by krousdb

I have run 0W-20 Mobil 1 on the Prius for 62k miles, changing every 12 - 15k miles. No problems so far.

my main reluctance to going to full 0w20 in my car is my belief that its suzuki motor isn't as well engineered or built as the honda/toyota units. i probably don't benefit from the same tolerances that permit you to use it safely in those engines.

however, this is conjecture on my part. unless i try an oil pressure gauge, i won't know for sure.