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zMax 51-212 Engine Formula, 12 oz

4.8 out of 5 stars 54 customer reviews
| 13 answered questions

List Price: $19.95
Price: $13.22 Free Shipping for Prime Members
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  • Increased gas mileage
  • Reduced wear on vital parts
  • Improved performance
  • Extends engine life
  • Reduced emissions
3 new from $13.22

Product Information

Technical Details

Brand zMax
Model 51-212
Item Weight 1 pounds
Product Dimensions 8.7 x 4.4 x 4.3 inches
Item model number 51-212
Manufacturer Part Number 51-212
OEM Part Number 51-212
Vehicle Service Type all-terrain-vehicles;utility-vehicles;street-sport-motorcycles;off-road-motorcycles;street-cruiser-motorcycles;street-touring-motorcycles;street-motor-scooters;snowmobiles;marine-personal-craft

Additional Information

Customer Reviews
4.8 out of 5 stars 54 customer reviews

4.8 out of 5 stars
Best Sellers Rank #4,557 in Automotive (See top 100)
#16 in Automotive > Oils & Fluids > Additives > Engine & Oil
Shipping Weight 15.2 ounces (View shipping rates and policies)
Domestic Shipping Currently, item can be shipped only within the U.S. and to APO/FPO addresses. For APO/FPO shipments, please check with the manufacturer regarding warranty and support issues.
International Shipping This item can be shipped to select countries outside of the U.S. Learn More
Date First Available July 20, 2005


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Product Description

ZMAX Engine Treatment
  • 12 oz

  • Customer Questions & Answers

    Customer Reviews

    Top Customer Reviews

    By DHumps on February 20, 2013
    I normally don't write reviews for products but after using Zmax I felt I had too. I have owned five vehicles over the years and I do all my own oil changes and maintenance. My previous four vehicles I tried everything under the sun in oil and fuel treatments and never seen much if any results. Zmax is a different story.

    When I bought my currant vehicle in 2009 I had already gave up on any additive working and stopped buying them. My currant vehicle is a 2005 Nissan Sentra SER Spec V and it had 27,000 miles on it when I bought it, currently it has 81,000. Every time I fill up I reset my trip odometer and calculate my mpg manually, even though my car has a computer that is supposed to do that (but it's rarely right). Over the last 3.5 years of driving my vehicle I average 25 mpg and usually have to fill up on Friday. I have a 13.2 gallon tank and my low fuel light usually turns on around 240 miles. I would usually fill up around 260 to 270 and put in around 11 gallons of gas, and I do use the same gas station every fill up. Then one day my brother-in-law (who drives a Honda CRV 150,000+ miles a year for a delivery route) was talking about how he started using Zmax in his vehicle. He claimed he was getting 3 mpg more than before. I thought I'd give it a try on my next oil change at 80,000 miles.

    The first week and tank of gas I had Zmax in my vehicle I didn't notice a difference in the power or mpg. I thought another waste of money. Then half way through the second tank my car started running differently. I thought the accelerator was being too touchy and responsive. I was a little worried at first and then I realized that I was feeling more power! The second tank ran down and I went to the gas station to fill up.
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    I have a 1992 GMC Suburban with a 5.7L (350 cu. in.) that I've had since 1996. I religiously changed the oil every 3,000 miles. I currently have 332,000 miles on the original engine and was burning about 1/2 quart between oil changes before using ZMax. Immediately after using ZMax the oil usage went to zero! Since 2008 I've had no oil usage between oil changes! I know this sounds impossible but it's true. I've used many other products of this type but this is the 1st one that actually met it's claims.
    ZMax recommends that you use their product a couple of times a year but I now use it after every oil change as I think it is cheap insurance against engine wear and ultimate replacement.
    2 Comments 54 people found this helpful. Was this review helpful to you? Yes No Sending feedback...
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    This product is actually sold for less $$ on the actual zmax website. As of this writing (Feb 17th, 2014) the single treatment lists here for $15.31 + $9.99 shipping. You can make the same purchase on the zmax site for a few dollars less. And, for $3.00 more you can get the entire 4 part kit on the same site. Be sure to click on specials to obtain the free shipping discount code. (HINT: The bottle of Small Engine Forumla can be used in your car engine. It's the same stuff as the engine treatment. So the kit is an even better deal).

    Now for two amazing zmax stories:
    Story #1: I had just bought a Honda Accord with 110K and an automatic transmission. Upon taking it on the freeway I noticed a problem with the tranny that I hadn't picked up on while test driving the vehicle (darn it). Once the car hit about 60MPH the overdrive cut in (effectively a 4th gear). But the moment I backed off on the accelerator the overdrive would instantly disengage, then re-engage a moment later. The effect was quite jarring and happened every time.

    Out of desperation I bought a bottle of the zmax transmission treatment and added it to the car (I had seen the old commercials on TV where they drive a car treated with zmax hundreds of miles with no oil in the pan). Within a couple of days of adding the treatment the bucking of the overdrive cutting out and in had completely stopped, and NEVER HAPPENED AGAIN AS LONG AS I OWNED THE CAR.

    Story #2. This one's even better. I had a Toyota Corolla, again with the automatic transmission. Out of the blue the tranny started making a noise. A loud noise. It happened mostly while backing up (gear shifter in reverse). It was a terrible scraping noise that sounded like metal on metal, like two garbage can lids being rubbed together.
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    Despite regular oil changes with synthetic oils, my high mileage 1999 Jeep Grand Cherokee 4.0L has a noisy sticky lifter on an exhaust valve which could not be addressed with any engine flushes (including Seafoam). But when I use Z-Max it's only noisy when the engine is cold and quiets down as soon as the engine reaches operating temperature; this is the only additive on the market that can acheive this (beleive me, I've tried them all). Since having this condition professionally repaired is almost as expensive as a remanufactured long block, I decided to wait. Z-Max has continued performing in this manner for over 9 years and over 120,000 miles at this point (the long block is now appropriate and is finally scheduled for this year). The fact that Z-Max can accomplish this feat that no other oil treatment can and keep the hunting/bad weather ride going, speaks for itself; I use it with every oil change in the Jeep and my Mercedes Benz. If only Amazon stocked this product and I could use my PRIME membership for free shipping, instead of taking a trip to the Auto Parts Store...
    1 Comment 32 people found this helpful. Was this review helpful to you? Yes No Sending feedback...
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