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Discussion Starter #1
Friend suggested I put lucas in with my oil. Read over the bottle, all the usual miracle oil claims, but I'm curious who on this board has used it. The stuff is incredibly thick...almost like caramel. Doesn't seem like the kind of thing you'd want in an engine. thoughts?
 

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I am using 20W50 Valvoline racing oil with high zinc in it along with Bars Leak rear main seal conditioner. Back in the day... STP oil additive was used religiously by many and it was quite thick. I never used Lucas but I assume its like STP? If it is I wouldn't think it would hurt.
 

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I change oil in 1 of the NAPA trucks here in town and they have been putting in LUCAS every change sense new. The truck has over 400,000 miles on it now with nothing but normal service. :cheers
I've also used their power steering stop leak/conditioner with awesome results. Gets rid of that 'morning sickness' and stickiness found in some racks when it gets cold outside.
 

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67 Basket Case Restorer
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Lucas oil stabilizer is a great product and I used it for many years in my Pete until the cost became to expensive. It only takes a small amount for 5 quarts of oil and be sure to add it while the engine is warm and running.
 

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Discussion Starter #8
just did the oil with castrol high mileage (love the extra additives BP throws in there) and a bottle of lucas. she seems to run just fine despite the gluelike nature of the stuff.
 

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Discussion Starter #10
my understanding is the high mileage oil should handle that. the zinc additive is to help the valve seats, correct? Castrol high mileage is loaded with additives for wear resistance and such, which (i assume) would be effective on the valve seats. may be wrong on that front though.

Other side of that is i've struck out finding ZDDP here in town...neither o'reiley or autozone had it, haven't tried pep boys yet, but they never seem to have what i want.
 

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The ZDDP is for the lifter to cam contact area. I thought it was just needed for break-in.
The valve seat concern was with the lead being removed from the gas. Hardened valve seats would take care of that and if the heads have been rebuilt in the past 20yrs they should have been upgraded already.
 

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Discussion Starter #12
ah, my mistake...I'll look a bit harder. I assume without it the lifters wear down much faster? Also, what's the proper spacing for the exhaust and intake and how often should I be checking that?
 

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Zero Lash. you have hydraulic lifters. ZDDP is needed in all cars and trucks with flat tappet camshafts, at all times. Cars like yours. The high load in a small area on the old flat tappet cams neccessitates this. Think of a high heel shoe walking on a wet lawn versus a snow shoe. You get the picture. ZDDP is in Shell Rotella diesel spec oil (what I use) and Delo diesel spec oil. You can also google ZDDP PLUS and order it on-line to add to your oil. Do not run without it, or you WILL be wearing out cams and lifters.
 

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The ZDDP is for the lifter to cam contact area. I thought it was just needed for break-in.
The valve seat concern was with the lead being removed from the gas. Hardened valve seats would take care of that and if the heads have been rebuilt in the past 20yrs they should have been upgraded already.
i agree, its only needed for break-in but im sure it doesnt hurt anything to keep running it.:cheers
 

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67 Basket Case Restorer
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i agree, its only needed for break-in but im sure it doesnt hurt anything to keep running it.:cheers
Only if the oil has sufficient zink to prevent metal to metal gall. If you are using a garden variety oil, the ZDDP is a must. There are very few automotive oils with sufficient zinc anymore.
 

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Again, if you use ZDDP just for break in and discontinue its use during regular operation after the break in, you are headed for mechanical failure. You need ZDDP in your engine at all times it is running.
 

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Discussion Starter #20
Zero Lash. you have hydraulic lifters. ZDDP is needed in all cars and trucks with flat tappet camshafts, at all times. Cars like yours. The high load in a small area on the old flat tappet cams neccessitates this. Think of a high heel shoe walking on a wet lawn versus a snow shoe. You get the picture. ZDDP is in Shell Rotella diesel spec oil (what I use) and Delo diesel spec oil. You can also google ZDDP PLUS and order it on-line to add to your oil. Do not run without it, or you WILL be wearing out cams and lifters.
revisiting this...isn't there a few thousandths gap between the rocker and the valve itself when the valve is closed. that's what i was talking about, although I had a rough time explaining what i meant.

back to ZDDP, i'm having a difficult time understanding the benefits. I get your stiletto/lawn comparison, but any zinc additive will be softer than both the cam and the tappets, so all it would really do is provide a liquid barrier between the two. unless it somehow annealed to the tappet during operation, you're just thickening the liquid boundry layer, not preventing mechanical deformation. even if pure zinc were to bond with the tappet, it's a very soft metal and would deform almost instantly under the type of stress we're talking about.

Just playing devil's advocate, and I don't disagree that ZDDP probably does save engines...i'm just curious as to the details of "how".
 
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