Want better MPG? Change your oil!

[wood_e]

I thought I would let everyone know about my findings in a very unscientific test I did on my car.

I always used to run 10W30 castrol in my SHO in the summer. I noticed that I would never get over 21-24 mpg. I found some 5W30 on sale at wal mart and for my last oil change I put that in with a new filter.

I've driven 2 350 mile trips and I estimated that i got 27.5 MPG. Of course YMMV but I found this to be somewhat of an interesting find.

 

[Sho-Driver]

That's actually well known, but I prefer better protection over the better mileage.

 

[NotSoSlowSHO]

4 mpg?

Its in your head..... er... foot.

 

[TYSHO]

That's actually well known, but I prefer better protection over the better mileage.

I prefer using what's recommended and not some thicker oil which takes longer to thin out and cause for wear on start up.

 

[Sho-Driver]

10W-30 is not going to have any ill effects. 5W-30 IS recommended because of the gas milage claim. FWIW, I've recorded 32 mpg with 10W-30.

Start running that thinner oil hard and find out how thin it really is. If you live in an extremely cold climate, 5W-30 may be what you need. I run 10W-30 all year around and the motor is very strong with unknown, beat to ****, mileage.

 

[TYSHO]

10W-30 is not going to have any ill effects. 5W-30 IS recommended because of the gas milage claim. FWIW, I've recorded 32 mpg with 10W-30.

Start running that thinner oil hard and find out how thin it really is. If you live in an extremely cold climate, 5W-30 may be what you need. I run 10W-30 all year around and the motor is very strong with unknown, beat to ****, mileage.

Well, I bought a SHO with records of oil changes using the 10W throughout most of it's life and it was not pretty. What you want is something that will protect on a cold start up and thicker oils do not provide that.

 

[Sho-Driver]

The 10W is not thick enough to cause you problems. I've used nothing but 10W in both of my cars and they are damn pretty inside ;-) Sure, one of them has a pre-oiler, but that's only been on for about 15k miles.

I've seen even thicker oil run on a SC Street SHO that sees track time. The only problem there was the oil was too thick to really fit in the bearings and it boiled between the rod bearing and crank causing pits in the bearings.

 

[TYSHO]

Well when I said inside, I was referring to the camshaft lobes, they were worn badly and the car was never beat on.

Maybe it was just that SHO, though. I like to use semi-synthetic, if not full, so the oil doesn't break down with all the high rpms I use.

 

[Sho-Driver]

Higher RPM alone will not break down oil. Running regular oil too hot will. I run Mobil 1 with a Pre-oiler and a remote bypass in one car and regular Castrol GTX in the other. Neither show cam wear and both cars are driven hard.

 

[TYSHO]

Higher RPM alone will not break down oil. Running regular oil too hot will.

High RPM's = More Friction
More Friction = Heat

 

[Sho-Driver]

High RPM's = More Friction
More Friction = Heat

Yes, but that alone will not do it (IE: running it through the gears every now and again). EXTENDED HIGH RPM will heat up the oil if you do not have proper cooling.

 

[SHOZ123]

I prefer using what's recommended and not some thicker oil which takes longer to thin out and cause for wear on start up.

I prefer an oil that is thin enough when cold that it will flow and protect, and one that is thick enough under high rpms and temps to do the job there also. That's why I use a 5w40 synthetic. Which btw when used in my 200k+ Festiva gives me 2 mpg and cuts the oil usage by 75% compared to a 5w30 dino oil.
:corn:

 

[sdpatt]

My engine has used 10W-30 Casrtol GTX all of its life and it's [turn strong southern accent on] real purdy inside [turn strong southern accent off]. The oil chart in my owner's manual shows an upper cut-off temperature around 100F for using the 5W-30. My engine sees that for quite a few days during the summer.

 

[voogru]

thicker oil =friction
petrolium oil wont coat piston skirts
piston rings until proper engine temperature.
when at start up cold crap oil just cant make it to
the piston area, dont believe me?
take apart any well serviced engine and inspect
the piston skirts and ring area, you will find BURNT, CHEAP,
GARBAGE, PROMISE ITS THE BEST U CAN BUY OIL, CAKING UP
YOUR PISTONS AND ENGINE. OIL BURNT IN THIS AREA IS
THE LEADING FACTOR IN YOU CYLINDER WALL WEAR.
PROVE ME WRONG!
petrolium oil is the reason you are paying close to $3.00
a gallon these days, stop paying for petrolium products for your car
start using AMERICAN made synthetic oil.
save money , save engine failure
save horrible downtime,
save you head from worrying if your oil is too thin,
use 5w30 and beat up your car with confidence
cause synthetic oil is many times better at $6
a quart compared to $1.50 fossil oil pumped out
from the ground. :hpoop:

I agree with the first post here.
improved mpg with thin oil,
I found the same with my 1991 mtx sho
I was using 10w30 AMSOIL getting 27/28 mpg
I switched to thier best 0w30 series 2000 and mpg
jumped to 30/32 to my suprise, and to make most
posters here green with envy, oil has been in the crankcase
for 22k and its still clean on the dipstick. great extended life oil
for $50.00 worth of oil and filter from AMSOIL it last so much
longer than 5 gallons of anything you buy at discount auto!
DRIVE AMERICAN, BUY AMERICAN

 

[shomesomesho]

DRIVE AMERICAN, BUY AMERICAN

I do . . . but the engine in my SHO happens to be . . . Japanese.

 

[Sho-Driver]

save you head from worrying if your oil is too thin,
use 5w30 and beat up your car with confidence

Try beating your car on track for 30 minutes on that thin oil and watch a rod bearing spin quickly. Even quicker with an SC. Ask me how I know

 

[wood_e]

Wow I didn't mean for this to turn into a post war...

 

[40BelowSummer]

Doesnt look like a war to me, just a civilized exchange of opinions.

 

[ohfosho]

generally speaking, 5 W 30 is a good all around grade of oil...hence why its been on countless oil caps for the last 10 or so years. now ford (mainly) has mostly switched to 5 W 20. this is noticably thinner oil!

many people will see optimal protection and great range in a 5W40 oil.

5 is very thin...moves easily and quickly throughout the system to protect.
40 is quite thicker, and therefor less likely to seep through old gaskets (this is why most people use thicker oils...to reduce leaks)

remember the 5 (first#)refers to the viscosity rating for cold (initial startup/below operating temperature), and the 40 (last #) refers to the operating temperature/warm-hot viscosity rating.

now if you think that your oil is getting a lil to hot, then maybe you should look more into new engine cooling components*lower temp thermostat, bigger rad, better/faster fans (operating all of the time maybe), and a better waterpump? hows about some larger oil coolers?

afterall, if your oil is getting too hot, how hot is ur engine running?

information curtosy of jiffy ****! (i worked there for a lil bit)

 

[yamahaSHO]

The SHO's oil cooling system is sub-par. Oil temps go through the roof and peg gauges rather quickly.

You don't need something extra thin to get everything lubricated quickly. You can run the 10w and not worry. We're not comparing water to molasses here.