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Can I mix SynLube™ Lube−4−Life® with other oils?

Answers to the most frequently asked questions (FAQ)


Can I mix SynLube™ Lube−4−Life® with other oils?


YES, but it is NOT recommended !

In order to satisfy U.S. Military specifications SynLube™ Lube−4−Life® must be totally compatible with all previously certified Military Lubricants.

Under Federal Test Method Standard No. 791C, Method 3470.1 Engine Oils are expected to be homogeneous and completely miscible with all other engine oils with which they might be mixed in service. When oils are mixed in any proportion, there should be no evidence of separation either of the additives or of the oils when the mixed oils are heated to a temperature as high as 232°C (450°F) and cooled to a temperature as low as the pour point of the mixture.


SynLube™Lube−4−Life® satisfies the above Federal Test. Therefore any lubricant that confirms to U.S. Military MIL-L-46152E or MIL-L-2104F specifications is totally compatible with SynLube™ Lube−4−Life® .

Because SynLube™ Lube−4−Life® is chemically inert it will not adversely react with any commonly used lubricant or hydraulic fluid.

However, we do not recommend the mixing of SynLube™ Lube−4−Life® with large quantities of other lubricants, because the effectiveness and performance of SynLube™Lube−4−Life® will be substantially reduced.

The common Petroleum and Synthetic oils now on the market will still deteriorate and decompose at normal rates, even if they are mixed with SynLube™ Lube−4−Life®.

In other words, the long term permanent protection that SynLube™ Lube−4−Life® provides will be reduced or lost and the bulk oil will have to be eventually drained and replaced. This is due to the decomposition and sludge formation caused by the ordinary oil.

Therefore mixing of SynLube™ Lube−4−Life® with other oils should be avoided.

If SynLube™ Lube−4−Life® absolutely must be mixed with another lubricant, synthetic oils are always preferable to any petroleum product.


Some synthetic base stocks or additives are not compatible with other synthetics; therefore synthetic lubricants should not be indiscriminately mixed, even if they are individually compatible with SynLube™ Lube−4−Life®.

Once you mix another synthetic oil with SynLube™ Lube−4−Life® never mix it with another type or brand of synthetic or petroleum motor oil.

Drain the mixture as soon as practicable and replace with FRESH FILL of SynLube™Lube−4−Life® INITIAL FILL.

To fully understand how and why SynLube™ Lube−4−Life® is the "Best Lubricant" please read this more detailed web page:


SynLube™ Lube−4−Life®