Yes, for the life of your battery.  If you feel for that Thermoil® fails to live up to their promises simply return it to us, we will immediately issue a 100% refund of the purchase price no questions asked.

Good Question. There are about 30 different battery manufactures and there is a big difference between some batteries. In the past 17 years I have traveled across the country meeting hundreds of battery specialists, most agree that there are a select few that are better than the rest. I will not disclose them here, but if you'd like to know which batteries I think are the best, (per type of application) feel free to e-mail This e-mail address is being protected from spambots. You need JavaScript enabled to view it or call toll free at 800-221-5351.

Each bottle of oil contains 12 oz and the ounces are clearly printed on the bottle so you know how much oil you are adding to each cell. On the back of the bottle there are written instructions that tell you how many ounces of oil to add to each cell per type of battery. One 12 oz bottle of oil will treat most batteries (12-volt group 24, 27, 31 etc is 2 oz per cell, 6-volt golf cart battery is 4 oz per cell) unless you get into the bigger batteries such as a 4D or 8D. They take 4 and 5 oz per cell. The bigger the battery the more oil that is needed. On the other hand the smaller the battery the less oil that is needed. A lawn-mower or motorcycle battery only requires 1/2 oz to 1 oz per cell. What you want is no less than 1/3 inch and no more than 1/2 inch of oil layer in each cell. As to the question of do you have to remove any acid first the answer is usually not in the bigger batteries but yes in the smaller batteries. The simplest and fastest way which takes about two minutes is to take a hydrometer and suck some acid out of each cell and put it in some sort of clean plastic container. When you do this you are also checking to make sure that your battery is good by having the same specific gravity in each cell. If the specific gravity is much lower in one cell than the other cells take it back for warranty now before you add the Thermoil because your battery is probably going to die within 18 months. Thermoil will not help this. Now add the correct amount of Thermoil® to each cell as stated on the back of the bottle. After the oil is added take the small amount of acid that you removed from each cell and add it back to each cell until you bring the top of the oil to about 1/8 inch below the vent tube well. That is all there is to it. If you would have any remaining acid left over just store it in the empty De-Mister bottle to add back to the battery when the fluid level does get low. This way the chemistry of the electrolyte will remain the same. You should always wear eye protection and rubber gloves when servicing a battery because of the sulfuric acid.