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We have a number of clients who have been told by their equipment supplier, auto brand, truck brand, that the use of any additives in their equipment WILL void any warranty on the vehicle.

It is their right to say that, in the hope that many will believe their position. However legally, the situation here in New Zealand is much the same onus as in USA (see below)

In NZ, consumers have the Consumer Guarantees Act, and commercially we have the Fair Trading Act, which this falls under.

An engine manufacturer must evidence (prove) that the additive used ‘caused’ the malfunction of the claim. That is not so easy when a malfunction can be as a result of many influencers. (wear, oil type, fuel type, etc)


Read The Law That Protects You! All about after-market automotive and vehicle warranty consumer protection and more!

Magnuson-Moss Warranty Act of 1975 does not allow engine manufactures to void the warranty due to the use of an aftermarket part of engine additive / supplement. Link To Complete Document!

The only time an engine warranty can be voided is if the aftermarket part or additive / supplement can be proven by the manufacturer is being responsible for the failure of the equipment.

"Under the Magnuson-Moss Warranty Act and general principles of the Federal Trade Commission Act, a manufacturer may not require the use of any brand of filter, oil additives or catalysts etc. unless the manufacturer provides the item free of charge under the terms of the warranty.”

According to Caterpillar Warranty Bulletin (39):

“When auxiliary devices, accessories, and consumables ( filters, oil, additives catalysts, etc.), made by other manufacturers are used on Caterpillar equipment, the Caterpillar warranty is not affected simply because of such use.” It must be proven that the auxiliary devices caused the failure of the parts in question.

Cummins Service Bulletin # 3810340 / 02-Nov. 2006

Engine Oil - “Supplemental Friction Modifiers and Other Additives”

Cummins Inc. neither approves nor disapproves of any additives not manufactured or sold by Cummins Inc. or its subsidiaries.

Engine OEM Warranties

A diesel engine, indeed any type of engine, is a substantial investment for a company or individual. Protecting that investment is very important for both engine OEMs and engine buyers. As a result, engine warranties have emerged as a tenuous, sometimes contentious, relationship between manufacturer and buyer in which each has specific obligations with respect to the engine.

From the OEMs perspective, the “safest” approach is not recommending use of additives. Caterpillar, for example, states that “There are many different types of fuel additives that are available to use. Caterpillar does not generally recommend the use of fuel additives”.

This is understandable since it is the safest approach for an OEM. Moreover, many OEMs have their own private labeled additives (often manufactured by large additive suppliers); this is additional incentive to discourage use of non-OEM additives.

Biocides are an interesting special “case”. For many decades, biocides were the only option for temporary “relief” from bacterial and fungal fuel issues. As a result, biocides were “approved” by OEMs, governmental agencies and regulatory bodies.

In the United States, Federal law prohibits OEMs from voiding a warranty due to use of additives (Magnuson-Moss Act). This means that OEMs must prove/show that use of the additive caused damage and justifies voiding the warranty. Caterpillar, for example, states, “the warranty would not be honored if the cause of the failure was related to a fuel additive or even using a fuel that does not meet Cat specifications”.

With the above comments in mind, we answer engine warranty questions as follows:

  1. If I use Fuel Right additives in my fuel, will it harm the operation of my engine and more importantly, will it void my warranty?

  2. Fuel Right has been in continuous product development for more than 20 years and has been available in the market for the majority of that time. Fuel Right has treated more than a billion litres of fuel in cars, trucks, heavy equipment, planes, trains, pleasure craft and workboat marine engines. Engine brands include Ford, Dodge, Peugeot, Detroit Diesel, MTU, Caterpillar, John Deere, Cummins, International, Yanmar, Westerbeke, Mercedes, Volvo and many others.

During this time, Fuel Right has never experienced any claims where clients have experienced any negative impacts from use of Fuel Right products.

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