# Engine oil additive/flush prior to oil change



## jayvee53 (Aug 26, 2018)

Wondering about using one of the many oil additives (Amsoil, for instance) to the existing oil in a stock 400 engine 68 GTO prior to doing an oil change. I am just now taking ownership of the car and really don't know anything about the service history on the car. Going to use Lucas oil with the zinc properties from now on, but thinking maybe a little extra TLC with getting the old existing oil out might be in order.....anybody have experience in this area or advice? I have pretty much always thought such additives aren't worth the $$$$ as long as there is regular scheduled maintenance, but in this case, I dont know what the maintenance has been. Thanks!!


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## geeteeohguy (Feb 2, 2008)

Don't do it. Simply warm up the engine, drain all the old oil out, install new oil and filter and you'll be fine. I've been in the auto industry since '79, and have seen many of the 'flush' additives cause internal engine problems. The solvents can strip the oil film off of bearings and cylinder walls and camshaft lobes, causing scoring. On really dirty engines, it can loosen sludge and allow it to move around and plug up oil passages. No good. With detergent motor oil being the standard for the past 50 years, you have no need to use snake oil in your engine. Just drain and fill with high zddp oil and run it. I've worked on old antique cars for a long time, and some of those engines that were run prior to the mid/late '60's DID have a lot of sludge from the use of parafin-based non-detergent oils. In your case, that doesn't apply.


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## jayvee53 (Aug 26, 2018)

Thanks for the good advice...I was thinking any additive might do more harm than good!


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