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LiquiMoly in 2009 Mercury V-8 Engine

Hey Guys,



I would like to know whether it’s safe to use an oil additive (Liqui Moly) in my 2009 Mercury Grand Marquis with 4.6 V-8 engine.



When I graduated college and started the first full time job in Buffalo in January of 1954, I bought a 1950 Packard with the big straight 8 engine. Though it had low mileage, the engine oil was very fouled due to the previous owner never changing it. After a thorough flush and two or three close spaced oil changes, the car ran beautifully and got good fuel economy.



But, in the Buffalo winter, it was slow and sluggish to respond when started on sub-freezing mornings, so I poured a can of LiquiMoly into the crankcase one day. The following morning, it was BELOW ZERO outside when I fired up the big Packard, and to my amazement, the engine ran as if it was fully warmed up. Afterwards, the car’s fuel economy improved further, and I got better mileage than my buddies who owned little Chevys and Plymouths, 15-16 city and 21 highway; good for those days.



I continued to use LiquiMoly for years. but it became very hard to find, and I eventually stopped trying to find it.



I’m nearing 78, now, and driving what may be my last new car, a 2009 Mercury Grand Marquis with 4.6 liter V-8 engine, and only 12,000 miles, and would like to keep it running like new for more years, just like the '96 Merc I traded in for it.



Is Liqui Moly safe to use in modern Ford engines? I’m not sure I can find it at any local outlets, but, I’d like to try it, again, and don’t want to harm this engine.



Thanks,

Bob Greene

There’s no benefit to using it and you’re risking damage to your engine that wouldn’t be covered by the warranty. I think this is an easy decision.

Use the correct 5W20 oil and your engine should last a very long time. Use 0W20 oil, and it might last slightly longer. Don’t put any additives in.

Use a modern synthetic like Mobil-1 instead. This will surpass any benefits that Liqui Moly ever offered, give you slightly better mileage, and very good protection on cold starts.

Don’t put any additive in—today’s engines have much, much tighter tolerances than those old engines and thickening the oil at all with one of these can have a very negative impact on oil flow and engine life.

You don’t need LiquiMoly any more. Just use the recommended grade of oil and change it regularly and your GM will last a LONG time. The 4.6 is a very good engine with a history of long life and few problems.

Oil additives are unnecessary in modern cars.

Thanks for the reply. I wasn’t sure if the product suited modern engines, and am satisfied that it’s no longer needed.

Thanks for the reply. I wasn’t sure if the product suited modern engines, and am satisfied that it’s no longer needed.

Thanks for the reply. I wasn’t sure if the product suited modern engines, and am satisfied that it’s no longer needed.

Thanks for the reply. I wasn’t sure if the product suited modern engines, and am satisfied that it’s no longer needed. My previous Mercurys, like the 13 year old one I traded last year, all ran beautifully when I traded them; I just wondered if the additive would enhance its life or economy in any way.