Proper oil for older engine

OVERKILL

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I run a 5qt jug of Quaker State High Mileage 10w40 syn blend with a bottle of Schaeffer Moly EP in my 93 C1500 5.7l and it is great. Probably equals a 50 to low 60 weight, did the math once, think is was 15-16ish cst at 100c. but can't remember exactly. Have ran it for a while but will be switching to QSFS 5w40, Walmart sale, w the Moly EP for a while as I bought a bunch of it. I was running 5w30 but was burning oil, now consumption is way down. Once my stash of 5w40 is gone I will go back to the QS HM blend, great oil for the price. Last summer I ran 5w40 Rotella t6 and it was fine too. Run any 5w40/10w40 synthetic or blend and you'll be fine. Mobil has the 10w50 and Castrol GTX HM has a 20w50 which will work too esp if hauling or towing w it.
Amusing that this product doesn't really have much moly, according to the couple of VOA's done on here years ago:

100C Visc is 238.5cSt, the QS HM is 15.9cSt @ 100C. The Shaeffer bottle is 0.473L so added to the 5 quart bottle, would constitute 7.68%. Using Widman's visc calc, that gives us a blended viscosity of 18.69cSt, so about the middle of the xW-50 range, probably effectively a 15W-50 or 20W-50.
 

wlk

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Amusing that this product doesn't really have much moly, according to the couple of VOA's done on here years ago:

100C Visc is 238.5cSt, the QS HM is 15.9cSt @ 100C. The Shaeffer bottle is 0.473L so added to the 5 quart bottle, would constitute 7.68%. Using Widman's visc calc, that gives us a blended viscosity of 18.69cSt, so about the middle of the xW-50 range, probably effectively a 15W-50 or 20W-50.
It is odd how they picked the name. I use it to help raise the viscosity, it has some additives and it has helped reduce consumption nicely w my truck.
 

OVERKILL

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It is odd how they picked the name. I use it to help raise the viscosity, it has some additives and it has helped reduce consumption nicely w my truck.
Agreed, but, the name "moly" does have a certain reputation associated with it, so I kind of understand it. Many of the Liquimoly oils have little to no moly in them, even though it's in the brand, so from that perspective, it's the "identity", so it makes sense.

Yes, it has a pretty pronounced impact on the viscosity, so it could definitely reduce consumption in a worn/tired engine. Without knowing more details on the formulation, I'm hesitant to comment on how it might compare to just using a 15W-50 or 20W-50 though ;) .
 
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Aug 12, 2021
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Dripping Springs, TX
In Texas do you still need to have it?
It depends on your county and the how the vehicle is registered. Vehicles 25+ years old do not need any inspections (no smog, nor safety) if you are running “Antique vehicle” plates. “Classic” plate vehicles and regular plate vehicles require safety inspections and testing the gas cap seal. In certain counties (Travis, Williamson, and counties in/near DFW and Houston) they do emissions inspections. If your inspection fee is only $7, you live in a non-emissions test county like me.

I use Rotella T4, Mystik JT-8, or Providence syn blend HDEOs in my 70’s land yachts, 76 Gremlin, ‘77 F250, ‘79 Bronco, and ‘85 GMC Conversion van.
 

wlk

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It depends on your county and the how the vehicle is registered. Vehicles 25+ years old do not need any inspections (no smog, nor safety) if you are running “Antique vehicle” plates. “Classic” plate vehicles and regular plate vehicles require safety inspections and testing the gas cap seal. In certain counties (Travis, Williamson, and counties in/near DFW and Houston) they do emissions inspections. If your inspection fee is only $7, you live in a non-emissions test county like me.

I use Rotella T4, Mystik JT-8, or Providence syn blend HDEOs in my 70’s land yachts, 76 Gremlin, ‘77 F250, ‘79 Bronco, and ‘85 GMC Conversion van.
Wow $7 for an inspection is cheap, mine for this year for mechanical and emissions was $100, last year $87 here in PA. That x's 3 vehicles so far and 2 to go ugh. Thankfully they have needed nothing mechanical wise so far but 1 of the upcomings will though sadly.
 
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Feb 17, 2010
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Chicago
I'd worry about protecting a camshaft over the worry of poisoning a catalytic converter.
I'd rather replace the converter if it was my dime and my time on my vehicle.
I agree with the Euro 40 weight oils are a great value.
 
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I can't speak for the 350's but yes there definitely was a problem with certain 305's that had camshaft issues back in the 80's, supposedly it was a metallurgy issue where they didn't get the hardness right so the cam lobes would get wiped and possibly even a broken camshaft. The 305 was actually fairly decent it was right up there with all the other small block Chevy's but they did have their issues.

I would use an HDEO that is also certified for gas such as Chevron Delo or Mobil Delvac, the Chevron does have it in 10w30 if you're lucky to even find some but most likely you'll find 5w40 & 15w40, for that old engine I'd use 5w40.
 
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Don't worry about the cam/lifters, if it's going to go flat, nothing will prevent it.

At 44k miles, I wouldn't worry about that pellet type converter either. Oil kills them slow, rich mixtures a lot faster.

Keep the engine in good tune. Avoid the urge to mess with the carb other than filter changes.
 
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The manual in my 83 Silverado with the 305 recommends a 10w30 oil which I am running. ;)
 
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