5.0 out of 5 stars My Husband Swears By This Stuff, A Must-Have for Diesel Trucks

M.&.J. · June 18, 2025

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5.0 out of 5 stars Good product

L. · June 6, 2025

This and Amsoil…you can’t go wrong!

5.0 out of 5 stars Needed to lubricate def engines.

T. · October 25, 2024

A many year diesel mechanic recommended this product to properly lube the newer def engines. I checked all over the web and this was the best price I could find. Fast shipping-

4.0 out of 5 stars An act of faith.

E.M. · January 8, 2014

I say this because I really don't know if this product will increase the life of my engine or any fuel-system components. I have been using it for two months (2000 miles per month) and I have not noticed any increase in fuel mileage (this product does not promise increased fuel efficiency) nor power.That said, I can tell you that after two tankfuls, I got a check engine light, the code was for an "unbalanced" fuel injector. It turns out that on VW TDIs the fuel injectors are also sensors for combustion pressure. The check engine code was saying that there was uneven fuel delivery and hence uneven pressure. I thought this might be related to the additive, perhaps causing something to unstick (vehicle had 85,000 miles when I started using it) as it loosened things up. I did not notice any unusual or rough running, so I ignored the light, and after two weeks it went out and has not come back on.So, is it worth it? I checked the price of a fuel pump for this vehicle. Around a grand, plus extensive labor. I have seen on the blogs that high-pressure fuel pumps for VW diesels often fail prematurely and that this is often related to fuel issues (gasoline contamination, primarily). It was with this in mind that I decided to add a lubricant to every tank of fuel. I hope to never change the high-pressure fuel pump, and the additive cost over the next 90,000 miles is only $75, so I took the chance.UPDATE: I have put over 25,000 miles on the car since starting use of the additive. Fuel mileage has gone up, particularly this Summer, by 1-2 mpg. It runs smoothly, and I have had no check engine light.Final UPDATE: Hello Dieselgate comrades. Yes, I sold my beloved TDI back to VW with 149,000 miles on it (39,000 miles more than the first update). Never had any trouble with the fuel pump. I believe this product definitely extended the life of the high pressure fuel pump. My fuel mileage never decreased at all over my entire ownership. So if you have a diesel vehicle of any sort, this is likely a good investment. I did however, need a new DPF and several exhaust sensors at 149,000. I stopped using the car at this time, as the repair cost was almost $4,000 and the buyback was already being offered. I wish the diesel ownership experience was better overall. The exhaust after-treatment systems are complex and prone to expensive repairs. But you can't beat the torque...

5.0 out of 5 stars ... injection pumps on my farm equipment due to the poor lubrication of post 2007 ultra low sulfur diesel fuel

A.C. · February 21, 2016

Started to use this product after loosing two injection pumps on my farm equipment due to the poor lubrication of post 2007 ultra low sulfur diesel fuel. Mechanic had told me that the bio diesel blends had all the lubrication I needed, patently false. The B20 doesn't lubricate as well as the old low sulfur fuel and it helps to emulsify water and get it past the water separator. This product helps to de-emulsify the water and keep it in the water separator and out of the injection system. It also does a fantastic job of lubricating the injection system. To the extent that you can hear the difference. I have 8 diesel engines I care for and they all run smoother and quieter with this product than without. The noisiest engine was the 7.3 IDI in my old ford truck, that beast used to sound like it had 19 monkeys swinging ball peen hammers against an anvil under the hood. Now I can actually hear my wife when shes talking to me while we drive around in the old beast. I don't claim that any of the engines produce more power or get better fuel economy with the lubricity formula, but they sure do run better. Haven't paid to have an injection pump rebuilt since using this. It's also what the diesel injection shop I use recomends.

5.0 out of 5 stars Great Stuff for our 1994 Winnebago

U. · January 2, 2024

We use this in our 1994 Winnebago and get 10-11mpg. Great stuff! The bottle make it real easy to add as we use the whole bottle. Beats having it in a gallon and having to measure out each time. Great product and Great Service from these folks.

5.0 out of 5 stars Great fuel additive

B.G. · January 11, 2024

Been using it for years it's Good lube for for diesel fuel

5.0 out of 5 stars Added two mpgs

S. · June 26, 2019

I bought this package since the price per ounce was much more palatable. I have a 2000 Dodge Ram with the diesel, and I see on average a 2 mpg boost with this product.