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expired Posted by WiseFuel971 • Dec 16, 2021
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expired Posted by WiseFuel971 • Dec 16, 2021

1-Gallon Marvel Mystery Oil: Oil Enhancer and Fuel Treatment

+ Free S&H Orders $35+

$8.40

$24

65% off
Walmart
104 Comments 32,416 Views
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Deal Details
Walmart has 1-Gallon Marvel Mystery Oil: Oil Enhancer and Fuel Treatment (MM14R) for $8.39. Shipping is free w/ Walmart+ (free 15-day trial) or on $35+ orders, otherwise select free store pickup where stock permits.

Thanks to Community Member WiseFuel971 for sharing this deal.

Note: Availability for pickup is limited and will vary by location.

Key Features:
  • Positive lubrication for smoother starting and longer tool life
  • Marvel mystery oil gallon dissolves gum and sludge that cut down tool speed and power output
  • Prevents rust and corrosion
  • Smoother riding and idling
  • Helps extend life and peak performance
  • Improves compression, power and MPG
  • Lubricates upper cylinder
  • Use in conventional, synthetic and 2 and 4 cycle oil
  • Use in all gas types, including diesel and ethanol blends
  • Available in a convenient 1-gallon jug
  • Marvel Mystery Oil 1 gallon is the original oil enhancer and fuel treatment
  • Danger: harmful or fatal if swallowed, the product is also combustible

Editor's Notes

Written by StrawMan86 | Staff
  • About this deal:
    • Our research indicates that 1-Gallon Marvel Mystery Oil: Oil Enhancer and Fuel Treatment (MM14R) is $14.75 lower (63.7% savings) than the next best available price from a reputable merchant with prices starting from $23.14 at the time of this posting. -StrawMan86
  • About this product:
    • 4.8 out of 5 stars rating at Walmart based on over 185 customer reviews.
  • About this store:
    • View Walmart return policy here. -StrawMan86

Original Post

Written by WiseFuel971
Community Notes
About the Poster
Deal Details
Community Notes
About the Poster
Walmart has 1-Gallon Marvel Mystery Oil: Oil Enhancer and Fuel Treatment (MM14R) for $8.39. Shipping is free w/ Walmart+ (free 15-day trial) or on $35+ orders, otherwise select free store pickup where stock permits.

Thanks to Community Member WiseFuel971 for sharing this deal.

Note: Availability for pickup is limited and will vary by location.

Key Features:
  • Positive lubrication for smoother starting and longer tool life
  • Marvel mystery oil gallon dissolves gum and sludge that cut down tool speed and power output
  • Prevents rust and corrosion
  • Smoother riding and idling
  • Helps extend life and peak performance
  • Improves compression, power and MPG
  • Lubricates upper cylinder
  • Use in conventional, synthetic and 2 and 4 cycle oil
  • Use in all gas types, including diesel and ethanol blends
  • Available in a convenient 1-gallon jug
  • Marvel Mystery Oil 1 gallon is the original oil enhancer and fuel treatment
  • Danger: harmful or fatal if swallowed, the product is also combustible

Editor's Notes

Written by StrawMan86 | Staff
  • About this deal:
    • Our research indicates that 1-Gallon Marvel Mystery Oil: Oil Enhancer and Fuel Treatment (MM14R) is $14.75 lower (63.7% savings) than the next best available price from a reputable merchant with prices starting from $23.14 at the time of this posting. -StrawMan86
  • About this product:
    • 4.8 out of 5 stars rating at Walmart based on over 185 customer reviews.
  • About this store:
    • View Walmart return policy here. -StrawMan86

Original Post

Written by WiseFuel971

Community Voting

Deal Score
+68
Good Deal
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Price Intelligence

Model: Diesel/Gasoline Fuel Treatment 1 gal

Deal History 

Sale Price
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Current Prices

Sort: Lowest to Highest | Last Updated 4/25/2025, 08:16 PM
Sold By Sale Price
Blain Farm & Fleet$26.99
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Top Comments

KMan
A teaspoon or so, per well-established practice, in case there's rust or seizure due to extended non-operation. No way to crack it by first manually turning it over. And, there's supposed to be some oil lining the cylinder walls, to lubricate the rings and minimize blow-by.
BeepBopBeep
Will this make my car invisible like the cypher in avengers?
KMan
I've used this to clean a very dirty and cruddy cylinder head, along with penetrating oil, and it worked pretty well. Has a not entirely unpleasant smell, like mint. I've also added it to the inside of cylinders through the plug holes before turning over an engine that hadn't run in several years, and it worked well there too, after first manually turning it over. There was this initial whitish smoke from the exhaust though, so don't be alarmed if you see some.

104 Comments

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Dec 16, 2021
2,363 Posts
Joined Feb 2007
Dec 16, 2021
ph7
Dec 16, 2021
2,363 Posts
Quote from Regroover :
Faith based lube. My uncle swore by it, and he was an engineer.
There is a weird oil nerd subculture (just visit Bob the Oil Guy forum if you can stand it). But if you talk to any actual petroleum engineers who make this stuff, they just laugh at the claims. Aging/used engines have far greater problems and threats than whether an engine's oil or gasoline contains miracle additives. But consumers love it - they'll even tell you they can hear their engine running smoother after adding it. It's bizarre.
1
2
Dec 16, 2021
150 Posts
Joined Dec 2015
Dec 16, 2021
robertvlee111pro
Dec 16, 2021
150 Posts
Quote from Sabretooth01 :
Saw this while I was on Walmart.com this morning I ordered 1 PU 2 shipped. It is the lowest price Ive ever seen do not know if mistake but I pickup after 11 today so well see.
I use this stuff for everything even in the vehicles oil. free ship/store PU where available for plus or with $35min Enjoy hope you like an have a nice day

https://www.walmart.com/ip/Marvel...n/16767858
I've used it exclusively as an additive to oil. What else do you use it for?
I need ideas because I just bought enough to get free shipping (5)
Dec 16, 2021
26 Posts
Joined Jul 2017
Dec 16, 2021
krizz90
Dec 16, 2021
26 Posts
How can someone be expected to feel comfortable putting something in their $30k investment when it is called "Mystery Oil"?
1
Dec 16, 2021
368 Posts
Joined Feb 2021
Dec 16, 2021
LeasedJet
Dec 16, 2021
368 Posts

Our community has rated this post as helpful. If you agree, why not thank LeasedJet

Quote from ph7 :
There is a weird oil nerd subculture (just visit Bob the Oil Guy forum if you can stand it). But if you talk to any actual petroleum engineers who make this stuff, they just laugh at the claims. Aging/used engines have far greater problems and threats than whether an engine's oil or gasoline contains miracle additives. But consumers love it - they'll even tell you they can hear their engine running smoother after adding it. It's bizarre.
Project Farm and several other YouTubers have done a lot of in-depth video comparisons showing before and after results including cylinder cam and complete tear down inspections. To summarize, it actually does make a little bit of a difference and exactly how much of a difference it makes will vary depending on specific situations.
1
Dec 16, 2021
1,009 Posts
Joined Jan 2015
Dec 16, 2021
gottahaveSD
Dec 16, 2021
1,009 Posts
Quote from TowHead :
This stuff is basically ATF.
Without looking into it, I thought that might be the case. I have a friend who swore by adding ATF to his fuel. Went to get an emmision test and they thought their equipment was broken.
Dec 16, 2021
1,009 Posts
Joined Jan 2015
Dec 16, 2021
gottahaveSD
Dec 16, 2021
1,009 Posts
Quote from LeasedJet :
Project Farm and several other YouTubers have done a lot of in-depth video comparisons showing before and after results including cylinder cam and complete tear down inspections. To summarize, it actually does make a little bit of a difference and exactly how much of a difference it makes will vary depending on specific situations.
Exactly this. Does a new car need something like this? Or maybe one with 150k miles that needs it's combustion chambers cleaned and smokes a little because of a little ring/cylinder wear.
Pro
Dec 16, 2021
1,864 Posts
Joined Sep 2016
Dec 16, 2021
vid1900
Pro
Dec 16, 2021
1,864 Posts
Although cleaner, it looks like the engine lost compression:

https://youtu.be/J3F3jDa2xhg

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Dec 16, 2021
2,723 Posts
Joined Dec 2006
Dec 16, 2021
NE0tekk
Dec 16, 2021
2,723 Posts
Quote from robertvlee111pro :
I've used it exclusively as an additive to oil. What else do you use it for?
I need ideas because I just bought enough to get free shipping (5)
I've been using it for fuel. I noticed my mpg increased by roughly 5-15% on the different vehicles I've used it on. Don't think it's a placebo effect since I've been measuring my mpg on my daily commute for the past 5 years and just started using this two years ago. Same amount of traffic, same vehicle, only thing that changed was this additive.

EDIT: Fixed when I started using it, COVID traffic definitely helps mpg too
Last edited by NE0tekk December 16, 2021 at 11:53 AM.
Dec 16, 2021
150 Posts
Joined Dec 2015
Dec 16, 2021
robertvlee111pro
Dec 16, 2021
150 Posts
Quote from NE0tekk :
I've been using it for fuel. I noticed my mpg increased by roughly 5-15% on the different vehicles I've used it on. Don't think it's a placebo effect since I've been measuring my mpg on my daily commute for the past 5 years and just started using this last year. Same amount of traffic, same vehicle, only thing that changed was this additive.
How much would you add to say 10 gallons of fuel?
1
Dec 16, 2021
2,723 Posts
Joined Dec 2006
Dec 16, 2021
NE0tekk
Dec 16, 2021
2,723 Posts
Quote from robertvlee111pro :
How much would you add to say 10 gallons of fuel?
4oz per the instructions. Seems to also have fixed the accuracy of my fuel gauge reading so it doesn't go to the last blinking bar right after hitting quarter tank. I've also tried the Lucas fuel treatment and although I got better mpg with that too, it wasn't as much as MMO.
Dec 16, 2021
908 Posts
Joined Sep 2006
Dec 16, 2021
nonplus
Dec 16, 2021
908 Posts
Don't make the mistake I did and put this in your Batmobile. You need DC oil for that.
2
2
Dec 16, 2021
72 Posts
Joined Sep 2015
Dec 16, 2021
JohnanthanS
Dec 16, 2021
72 Posts
Went to local Walmart to get some but still rang up at $20 hate when that happens so I just ordered online. Say what you want about this stuff it probably is just scented atf all I know is I do an oil change and the engine starts making a funny clattering noise, I add this and it goes away 'nuff said
Dec 16, 2021
1,577 Posts
Joined Nov 2007
Dec 16, 2021
suednim
Dec 16, 2021
1,577 Posts
When I worked for a major auto parts distributor we laughed about this stuff. The only "mystery" was why anybody would buy this stuff.
5
Dec 16, 2021
1,009 Posts
Joined Jan 2015
Dec 16, 2021
gottahaveSD
Dec 16, 2021
1,009 Posts
Quote from suednim :
When I worked for a major auto parts distributor we laughed about this stuff. The only "mystery" was why anybody would buy this stuff.
That's nice; what's your experience with adding this to a vehicle that has a lot of miles but still runs ok? Or does working for a parts distributor make one an expert?

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Dec 16, 2021
1,143 Posts
Joined Oct 2012
Dec 16, 2021
jetcityjef
Dec 16, 2021
1,143 Posts
Quote from iamverycrazy :
Can I put this on my Tesla?
Yes, you can put it all over your Tesla. Haters may even do it for free.
1

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