Lucas Oil10063 Engine Break In Oil Additive w/ TB Zinc Plus - 16 Ounce

I use this breaking in lawn mower engines. I add about 4-5 ounces to the engine. It helps the cylinder walls and rings break in properly. It was 7 dollars cheaper on amazon than at autozone. I have used this for years. I will buy again

used this lube for all my engines

I put this in my brand new GMC V8 engine. Then I changed the oil after 1000 miles. I’m not going to use it anymore because zinc is only good for break-in. Second oil change will be at 2000 miles, then regular intervals after that.

It's Lucas, good stuff

old cars, with flat tappet cam

It covered the area I bought it for it. It could use to be slightly larger

Have to consulting with professionals and reading a couple articles. I saw that the new oil being sold does not contain the amount of zinc that is needed in older engines. Even though this is sold as a additive to break in new engines this works great to be mixed with regular oil when doing oil change.

Got an older engine with mechanical pushrod-operated valves, tappets and so forth? Modern motor oils with the newest API SN, SM or SL ratings may not have quite enough of those good old zinc anti-wear additives to keep those cam followers and other "wackity bits" happy. The manufacturers have been reducing those levels of zinc bit by bit over the past several years to meet newer American Petroleum Institute standards designed to keep the newer catalytic converters happier. That's OK for vehicles with hydraulic lifters and such, but that's not such great news if you're tooling around on some nice old school clickety-clackety classic.Aside from using it for its intended purpose of breaking in a freshly-rebuilt engine, just about two ounces per quart of motor oil of this Lucas goo will keep those tappets happy as they can be. You don't need to overdo it: a little dab will do ya. A single 16 ounce bottle should cover maybe four or five oil changes, depending on how much you're topping off in between them.Adding just a couple of ounces of this "Lucas Oil 10063 Engine Break-In Oil Additive" to whichever oil one uses was recommended by guys who really know what they're talking about over on the superb 'Unofficial Royal Enfield Community Forum', and you know what? Since getting my own 2005 Bullet 500 single about 14 months ago and more than doubling the mileage on its clock, adding well over 5,000 miles, using this goo I have yet to have needed to adjust its tappets even once--normally a very common regular maintenance task of the breed. Nope: Not one time. I check them, sure, but there's just no wear.