Gumout question and answers.

Find below a comprehensive Q & A about all things Gumout


Can you provide any explanation for how your high mileage Regane products differ from the standard ones?

The high mileage version of Regane has a friction modifier added. This helps protect against wear in the upper cylinder which is a common issue with older vehicles. If the cylinder wall is compromised over time, it can allow oil from the crankcase to enter into the combustion chamber causing excess exhaust smoke. This can cause a vehicle to fail state emissions testing. It also reduces heat allowing a more productive combustion process which equates to restored power and fuel economy.


Is there any reason to NOT use a HM fuel cleaner in a low mileage vehicle? Our portfolio is based on a stair stepped approach.

As you move up the value chain, you will find that each product has incremental claims and benefits and along with this the retail price increases accordingly. We did this to ensure that there was a product to fit every need and price point. While the high mileage products offer benefits that are targeted at older engines, they will also work just as well on newer vehicles especially when used early on as part of your regular maintenance program. It’s better to stop the issues that cause problems early on than to deal with them later.


Does HM with Regane have more friction modifier than your standard products?

If you are referring to Regane Complete Fuel System Cleaner, it doesn’t have any friction modifier in the formulation. The level of friction modifier in the High Mileage version is lower than what is found in our All in One Complete Fuel System Cleaner + Ethanol treatment, but typically Regane High Mileage is also lower priced.


Recently posted on promo board, O’Reilly AP is closing out Gumout Regane CFSC and Regane HM 6oz concentrated bottles and it appears replacing them with 12oz formula bottles. O’Reilly Gumout All in One also going to 12oz bottles too. Is this going to be the new standard bottle for other retailers going forward?

We worked with O’Reilly on the larger sized products because they felt their customer base preferred the larger size. At this point, these larger sized Gumout products will only be at O’Reilly


Will the new bottles still treat the same amount gas as they did previously?

The treat rate is slightly lower (19 vs 21) based on recent OE trends that show the average size of fuel tank is roughly 16 gallons which O’Reilly is also aware of.


And will they have the same amount of PEA as the concentrated bottles?

The PEA potency is still the same just treating 2 fewer gallons than the old bottles.


I have noticed Autozone has a new line of Gumout Expert series products. It seems these products come in a bottle that has more treatment in it. They have 10 oz as opposed to 6 oz. Is there any other reason I should be looking at the Expert series of Gumout Regane instead of Gumout Regane at walmart? Are there any notable differences?

We often work closely with our retail partners such as AutoZone to understand what they feel their consumers are looking for. That feedback resulted in the Expert Series line of products, specifically made for Auto Zone. The treat rates are the same as the 6 oz bottles, and the All in One which is in a 10 oz bottle at most retailers also has the same treat rate. The product efficacy is the same. Each retailer has different philosophies and strategies for providing products to their customers. We try to accommodate them whenever possible, but if your purchasing preference doesn’t align with theirs, you will be able to find quality Gumout products at other retailers that better suit your needs.


I was wondering if Gumout (and other PEA additives) are equally effective regardless of the type of driving done? I have always assumed that a lot of short trips with many shut offs and starts would allow the additive to sit in the fuel injectors and on the valves longer….thus being more effective than a tankful of treated fuel used on one long highway run?

There are many factors that influence the build-up and removal of deposits. These include temperature, humidity, driving habits, engine design and even the particular location within an engine. Short trips with many stop and start cycles create many opportunities for deposits to build. Each time the engine is shut off, any fuel remaining on injectors and valves will cook forming gum, varnish and carbon deposits. It is true that treated fuel will then have increased contact time with previous deposits, but this may be offset by the tendency of deposits to build under stop-start conditions. Some of the test programs behind Gumout treat recommendations are based on running conditions that cycle between steady speed to heat the engine to operating temperature and hot soak to allow deposits to build, with clean-up evaluated under the same conditions. However, we do not have data to make a direct comparison to say whether a steady run is better than short trips for clean-up. Our advice is to treat a tank of fuel and drive normally as needed.


In DI engines…is it a waste to use anything more than ‘Fuel Injector Cleaner’ since the additized fuel never touches the valves

Since the injectors in DI engines are located in the combustion chamber instead of the port, they are now in an extremely volatile environment with temperatures reaching 600 degrees and the explosions from combustion essentially pressure cooking carbon deposits onto the tips of the injector. A standard fuel injector cleaner normally uses a detergent called PIBA. In high enough doses, these do a good job of cleaning port injectors (but not the combustion chamber); however, in DI engines, a more potent detergent such as PEA is needed to clean those deposits along with the rest of the combustion chamber. Regarding valve clean up in DI engines, that is a tougher issue to manage; however, they can still be cleaned but will require either a mechanical breakdown of the engine to manually clean them or a more efficient option is to use a product that can clean the valves by being introduced through the air intake or through a vacuum line. Gumout has a Direct Injection Valve cleaner aerosol that can be sprayed through the air intake/throttle body to clean valves and ports. For those that are more mechanically inclined, our Multi-System Tune-Up can be drip fed into the appropriate vacuum line and achieve the same effect, but there are risks of vapor/hydro lock which will severely damage an engine, so we recommend this method to only those that are very experienced in this type of procedure.


How effectives are the newer PEA additives run through the fuel of a carbureted engine?

I realize there are fewer and fewer of these on the road but do they assist in keeping jets clean or is a manual cleaning still the best practice? This comes down to a preference of how you want to clean the carb. Products with PEA at high dose rates can poured into the gas tank and do a great job of cleaning jets and other parts of the carb; however, often times areas not reached by the spray of fuel become dirty and therefore a spray carb cleaner would be the better option plus many spray cleaners have a straw that can be attached to the nozzle allowing for pin point cleaning.


Any advantage to running a maintenance dose at each fill up? If so what would the treat rate be per 10 gallons of fuel? Thanks.

Many of our mid and upper tier products state to use the product every 3000 miles because they remove carbon deposits from fuel system parts and help keep deposits from reforming up to this mileage number. Keep in mind, most fuel additives that state to use them every fill up means that they don’t have a potent cleaning agent or don’t have a high enough dose of a that quality cleaning agent. And, typically using a product every fill up is a more costly option, however, if you have a very dirty system or if you haven’t used a fuel additive as part of your regular maintenance schedule when you drove it off the new car lot, using one of our fuel additives at every fill up will offer additional cleaning than when used every 3000 miles. The products in our portfolio that have a friction modifier (Regane High Mileage, All in One and Multi-System Tune up) offer wear protection and would definitely offer more protection when used at every fill up. So if you feel you want that extra level of cleaning, feel confident that you will achieve that by using it every fill up, but once the fuel system is relatively clean and regular use of a quality additive that states to use it every 3000 miles is used after that, any additional application for cleaning purposes is probably overkill and massive overtreatment could possibly affect oil viscosity due to fuel passing past the piston and into the crankcase. Regarding treat rates, they vary by product, but on the back of each label, you can find how to ration the product to fit your vehicle’s tank size.


If not considering fuel stabilization as a factor, which product would be most beneficial for small 4 stroke engines and OPE?

Gumout Regane, Regane High Mileage or All-in-One complete fuel system cleaners offer strong clean-up performance wherever deposits may be in the engine even on small 4 stroke/OPE engines. Gumout Multi-System Tune-up is another great choice when several small engines are to be treated. Use about 1-2 ounces of Regane or All-in-One per 3 gallons of gasoline. If using 2-cycle fuel also add the recommended amount of oil. Use about 1-2 ounces of Multi-System Tune-Up per gallon of gasoline or diesel fuel. If fuel stability is an issue use the Multi-System Tune-Up for both gasoline and diesel.


I saw a video on the Engineering Explained YouTube channel talking about fuel additives. He dug up some research papers from SAE that used an engine with brand new cylinder heads and intake valves and had more deposits on the heads and valves using a fuel additive designed to remove deposits versus gasoline with no additives at all. He also mentioned in the video that PEA is the best at removing deposits that do form versus other additives. Would Gumout be more beneficial to the average user if he/she used it on a car that was not brand new?

Additives used in SAE research papers may or may not be the same as commercial products. Not every formula under development works well enough to become a viable product. We know that some additives used on a dirty engine can remove carbon deposits from intake valves and redeposit the same carbon onto combustion chamber surfaces including the head and piston tops. That is why Gumout formulations use a high quality PEA balanced with other synthetic additives to remove deposits from the entire fuel system. When treating a dirty engine, deposits are removed from all these areas to restore performance. Use Gumout for the initial clean-up and then use it regularly to maintain peak efficiency, removing deposits before they can build to reduce power and performance.


I treat my 2015 Civic with a cupful of Gumout with Regane All in One each week. I also add a bottle about 500 miles before a oil change. Is there anything I am missing. Throttle body is sprayed every 30k with Gumout DI cleaner.

Kudos to you for nailing the fuel system/car care maintenance process. The only other question I would have for you would be if you store your vehicle for extended periods of time. If your Civic is not driven regularly, a fuel and oil stabilizer can offer protection from varnishes and gums that can negatively affect performance when you go to fire up your car again. Our multi-system tune-up product can help you stabilize your fuel and oil and ensure you fire up the next time you start your Honda. Other than that, your regular maintenance schedule is spot-on.


Given that it typically takes several miles of driving before an engine is fully up to temperature, are all Gumout products effective at cleaning during this initial engine “warmup” period or does Gumout products only clean in high temp (engine is at operating temperature) environments?

Yes, Gumout products clean at low temperatures too. But the real challenge for fuel additives is in high temperature environments where lower quality cleaning agents burn up before they can do what they are supposed to do. Mid to high doses of PEA can withstand the heat from combustion and clean cylinder heads, piston tops and combustion chamber (and GDI injectors). This is what differentiates a gas treatment or fuel injector cleaner from a complete fuel system cleaner. CFSCs clean these parts as well as intake valves, intake ports and port/indirect injectors. All of our complete fuel system cleaners and our Multi-System Tune-Up product have PEA, so they will work at all temps.


After adding a bottle of Gumout All-in-One or Multi-System Tuneup and running the vehicle until almost empty, would it be beneficial to add a smaller dose at every fill up versus every 3000 miles per the instructions?

Overall we recommend using the complete treatment once every 3,000 miles. This is a convenient way to maintain vehicle performance at a high level. There is also strong test data to support this approach. However, a small dose at every fill-up is still an option if that is your preferred method of application. We do not have data to support a specific dose, but we would use about 2-3 ounces of All-in-One or 4-6 ounces of Multi-System Tune-Up to a tank of fuel.


Please add measuring bars on bottles. I’d like to split the 35 gallon AIO between 2 vehicles. It would also help with maintenance dosing.

Thanks for the insight, I will take this into consideration for our next label update.