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5w20, better gas mileage?

  • Thread starter Thread starter 2000GTNY
  • Start date Start date Jun 18, 2006
2

2000GTNY

New Member
Jun 21, 2005
31
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0
Albany, NY
Jun 18, 2006
#1
  • Jun 18, 2006
  • #1
If I ran 5w20 synthetic instead of 5w30 Mobil 1, would I get better gas mileage like some suggest? It seems like that is what I am reading as the reason for the switch in Ford putting it in the newer cars.

What are your thoughts? My Ford Escape calls for 5w20 so I could just buy the same for both vehicles if I will get better fuel economy.

Something tells me my mind is clouded...
 

trailblazr81

Member
May 17, 2003
571
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16
Hollister, Cali
Jun 18, 2006
#2
  • Jun 18, 2006
  • #2
I cant see how going from 5w-30 to 5w-20 will give you any noticable power difference or mileage. Maybe something like .2 miles per tank??
 
2

2000GTNY

New Member
Jun 21, 2005
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Albany, NY
Jun 18, 2006
#3
  • Jun 18, 2006
  • #3
I can't believe it either. It seems to be the general consensus that the motors didn't change, but the oil recommendation did. CAFE standards are mentioned which leads me to believe that there must be a tad bit better gas milegae to be had from the light weight oil.

BUT, like I said in my first post, my mind might be clouded! I'm no scientist
 
P

Pennywise2

Banned
May 16, 2006
1,379
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0
Jun 18, 2006
#4
  • Jun 18, 2006
  • #4
It wouldn't make much of a difference.I would stick with 5W30 Mobil 1.
 

sgarlic

Founding Member
Apr 21, 2001
3,085
1
56
Jun 19, 2006
#5
  • Jun 19, 2006
  • #5
Nothing noticeable. However, I lost around 1/2 to 1 full mpg going from 10w30 to 20w50 in my ZJ. The 5w30 to 5w20 thing was done to meet CAFE standards. If you want to read more about it, check out http://www.bullittarchive.com/7002.htm

I'd run whatever is thinnest and you can still maintain good oil pressure with. I run 5w20 here in AZ all year, but according to lots of people, that's too thin. However, my oil pressure readings at hot idle are just as good as people running 5w30.

Some people just follow the crowd.. and don't do their own research.
 
U

Uncle Meat

Banned
Jun 13, 2002
0
1
0
Prattville, Alabama
Jun 19, 2006
#6
  • Jun 19, 2006
  • #6
2000GTNY said:
I can't believe it either. It seems to be the general consensus that the motors didn't change, but the oil recommendation did. CAFE standards are mentioned which leads me to believe that there must be a tad bit better gas milegae to be had from the light weight oil.
Click to expand...
This is true. Ford did change almost the whole vehicle fleet from 5W30 to 5W20 for an improved C.A.F.E. rating. Yes a 5W20 oil is thinner thus easier to sling around in the motor and will increase gas mileage, but as stated before the difference is a minimal amount that the average driver wouldn't be able to measure effectively. It may only be .2 as stated above, but when you multiply that .2 by all the different Ford vehicle lines they made this change to it adds up and made a significant impact in the overall C.A.F.E. rating.

So does it save gas? Yes.
Will you see a difference? Probably not.

U.M.
 
R

RoadconeTuning

New Member
Apr 4, 2006
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Upstate, SC
Jun 19, 2006
#7
  • Jun 19, 2006
  • #7
when i went from 10w30 in my fiero to 20w50 i could feel a HUGE drop in power and noticed a 2mpg drop in gas milage.
 

CRZYHRSGT

New Member
Feb 14, 2004
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5.7 miles north of THE Ohio State University
Jun 19, 2006
#8
  • Jun 19, 2006
  • #8
Going from 5w30 to 5w20 isn't that much of a consistency change, whereas 10w30 to 20w50 is like going from Bud Light to Ginness. In this case you are gonna see a difference like was stated with the added bonus of less leaks. This was a fix we do on older VWs here at work when they started getting leaky all over the place.
 
2

2000GTNY

New Member
Jun 21, 2005
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Albany, NY
Jun 19, 2006
#9
  • Jun 19, 2006
  • #9
My Mustang prefers Corona with a lime!

Thanks for all of the tips!

So, for a final closure on this, would you say that I should/could run the 5w30 I run in my Mustang in my Escape with no issues, and no change in gas mileage? The Escape gets terrible mileage at highway speed and I would hate to do anything that makes it get even worse!
 
U

Uncle Meat

Banned
Jun 13, 2002
0
1
0
Prattville, Alabama
Jun 19, 2006
#10
  • Jun 19, 2006
  • #10
2000GTNY said:
My Mustang prefers Corona with a lime!

Thanks for all of the tips!

So, for a final closure on this, would you say that I should/could run the 5w30 I run in my Mustang in my Escape with no issues, and no change in gas mileage? The Escape gets terrible mileage at highway speed and I would hate to do anything that makes it get even worse!
Click to expand...
Yup.

U.M.
 

todd4566

Founding Member
May 24, 2000
1,075
0
36
California
Jun 19, 2006
#11
  • Jun 19, 2006
  • #11
I've used both grades and haven't observed and noticeable change in mileage. I'd go 5w20 if Walmart had it in the 5qtr jug (Mobil 1), but I usually run 5w30 instead. 5w20 is usually pretty hard to find too - even the Ford synthetic blend.
 

the98stang

Active Member
Aug 12, 2005
2,408
0
47
Clovis, CA
Jun 19, 2006
#12
  • Jun 19, 2006
  • #12
like others have said, you probably won't see a huge change in gas mileage. But your car will love you for using synthetic oil, especially if its Mobil 1
 

Dorsai

New Member
Aug 13, 2005
3
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0
Connecticut
Jun 19, 2006
#13
  • Jun 19, 2006
  • #13
RoadconeTuning said:
when i went from 10w30 in my fiero to 20w50 i could feel a HUGE drop in power and noticed a 2mpg drop in gas milage.
Click to expand...

I didnt realise Fiero's had huge power to begin with JKing
Those late model v6 cars were pretty damn quick for only making 140hp
 
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