What about zinc?

-
th

that is what I am going to do with the 318 when I get the cam in there. the Valvoline I think it is 15-20 racing oil with ZDDP in it already. expensive as hell though
The Lucas I run is like 37 bucks for five quarts. I get O'Reilly to price match whoever has it cheapest. That's usually like 10 bucks cheaper.
 
I use Rotella 15W40 oil in my slant.
It has a zinc content, around 1500ppm and that's the same as Royal Purple. You can by a gallon of Rotella for what a quart of Royal Purple costs.
 
Last edited:
I use the 15-40 diesel oil as well. I'm in Minneapolis and run my Valiant Wagon all winter. Mine isn't in showroom condition so I'm not worried about the salt doing anymore harm. Nothing better than rolling down the highway on a cold crisp 20F morning to go to work. Mine starts down to -15F then it starts to get cranky.
 
About running diesel oil in gas engines......
diesel
Run diesel oil if you want. I won't do it
 
Imo -The worse thing that you can do is "warm up" your car instead of driving it. The motor never completely gets warm and this builds condensation from the motor all the way through to your exhaust.


And I bet that you live by the same theory that running a motor without any coolant won't overheat either? What a joke!
 
And I bet that you live by the same theory that running a motor without any coolant won't overheat either? What a joke!

Hold on a minute. You do know that most race track ban coolant, correct?

I don’t agree with A56 on just driving it cold. My girlfriend got a Subaru crosstrek back in April. Know what that car does when you start it? Runs a high idle for about 2 minutes, turns the coolant light out and drops the idle to the normal level. So clearly, Subaru wants the car to warm up some before driving.

I do agree with A56 that one warm cycle is not enough.
The best thing you could do, is warm the car up with slight revs and get the temp to 180 or so, kill it and let sit for an hour to “heat soak” then go back out and get it hot again and let it run while revving the motor some to get it hot.
 
I agree with A56, but with a qualification.
Engines such as in taxis, trucks etc that are run for very long time periods have less wear over time than stop/start engines. That is because they are at continuous operating temp & the parts are getting lubricated & mate together as designed.
The plan should be to get the engine up to operating temp ASAP....& keep it there. Loading the engine when cold by driving the car will get the engine up to temp quicker. Just keep the rpms & load down until operating temp is reached.
 
I agree with A56, but with a qualification.
Engines such as in taxis, trucks etc that are run for very long time periods have less wear over time than stop/start engines. That is because they are at continuous operating temp & the parts are getting lubricated & mate together as designed.
The plan should be to get the engine up to operating temp ASAP....& keep it there. Loading the engine when cold by driving the car will get the engine up to temp quicker. Just keep the rpms & load down until operating temp is reached.
Yup. I have an old friend that I used to go in on buying retired police cars through the local auctions. We'd fix them up and flip them. Some we kept for a while. All of them without fail that were in running condition had very minimal engine wear. Most leaked from gaskets and seals, but the internals were excellent. Same theory. I agree 100% that unless an engine gets to operating temp and stays there for a prolonged amount of time, the oil and coolant never get hot enough long enough to boil out all the moisture and impurities. That's the main cause of sludge and varnish. Moisture gets locked in the oil and even with regular oil changes, with short trips, that oil that never drains completely will turn to sludge and varnish. Synthetic oils help greatly, but even they can break down if not driven for long periods on a regular basis.
 
All you people that spend your hard earned money foolishly on all these aftermarket products. Please explain to me WHY I've NEVER had any problems with any car by just using the cheapest oil I can find along with a can of STP?
 
I heard all the hype about gas and oil years ago and never worried about it. A lot of this stuff about lead and zinc is just hype. I've been driving old cars for 70 years and have used the lowest cost API/SP oil in their engines. I have never had a problem with with the valve train. I also have used regular gas. When unleaded came on the seen I used it with no real problems. The only problem I have had is with a car that had worn out engine at the time of purchase.
 
Last edited:
Hi Guys/Gals. I have a very stock 1974 slant six engine in my 1974 Duster. Stock motor and heads, mix of town and highway driving. I change the oil about every 2500 miles. I use NAPA store brand 10W-40 oil in it year round, altho I don't drive it outside in our Minnesota winters. I just warm it up in my garage. The NAPA store oil that I buy is API grade SP, repackaged Valvoline oil (at half the price - $11.99 for a five quart jug). This stuff is way better than what we had back in the day when my car was new. In any case, does my car need zinc additive? I kinda thought that by 1974, they didn't need zinc rich oil any more. So I don't use racing oil with zinc, nor do I add zinc at my oil/filter changes. What do you think? Slant six Dan, if you're out there, please weigh in. Thanks all!
anything with a flat tappet cam needs a high zinc content in the oils to prevent ware . now the diesel oil a high zinc cotant in them i use it & then swtich back to 20w50 with a lucus zink addative i have a 72 440 rebuilt to 71 specs
 
-
Back
Top