Engine Oil - '80-86 305 SBC

[Tynan918]

I spent $40 on 5 quarts of Lucas Hot Rod Motor Oil, specifically because it had zinc in it...

I can't keep paying that... Is zinc really a must have ?

I've had an '82 Impala, a '78 Impala, and an '86 Monte Carlo... Never had to use zinc specific oil in those engines...

I read and see so many other options...

Factory specs call for 5w-30, I've read others say 10w-30 in the winter and 10w-40 in the summer, some say use cheap oil and add a zinc additive, and I even read some using Rotella 15w-40 diesel oil...

I just don't and can't blow a bunch of money on zinc specific oil, and I'm sure there are cheaper options...

What exactly is zinc used for ?

How does 15w-40 diesel oil work in gasoline engines ?

Can someone explain and recommend something cheaper ?

 

[ELCAM]

I run the Rotella in my 350 olds motor, it is not in excellent condition, fair at best. It's days are numbered and expensive oil is not needed. Save the money for a new engine or a rebuild.

I have a new 350 corvette engine with flat tappet cam in my 72 Camino it gets the ZDDP (zinc) additive.

 

[pagrunt]

Awhile back I picked up some Valvoline high zinc oil at the local mom & pop parts store for about the same price as regular/current oil. As for cost, my '14 Silverado uses 8 quarts of that Dexos spec oil & makes $40 look good.

 

[olds307 and 403]

As said, on a stock peanut cam motor, the cheap oil should be fine. I had a fairly mild cam go flat in my Olds 350, wasted the bearings. I am going roller since this rebuild is thousands more than the the original $120 that motor cost me plus $400 rebuilt early heads.

 

[ck80]

I spent $40 on 5 quarts of Lucas Hot Rod Motor Oil, specifically because it had zinc in it...

I can't keep paying that... Is zinc really a must have ?

Until you make the change from flat tappet cam to roller, yes. Your cam will flatten lobes.

I've had an '82 Impala, a '78 Impala, and an '86 Monte Carlo... Never had to use zinc specific oil in those engines...

Unless they had a roller cam then you were causing wear in the engine.

I read and see so many other options...

Factory specs call for 5w-30, I've read others say 10w-30 in the winter and 10w-40 in the summer, some say use cheap oil and add a zinc additive, and I even read some using Rotella 15w-40 diesel oil...

Some oil manufacturers say the additives aren't a good idea because it screws up the blend and that thebadditive doesn't properly mix thoroughly so on so forth blah blah blah, but also remember they want their money

I just don't and can't blow a bunch of money on zinc specific oil, and I'm sure there are cheaper options...

The key part is reading through material spec tables for the brand and formulation, not using years old outdated ones, to find high levels of zinc and phosphorus

What exactly is zinc used for ?

To oversimplify it creates a coating on the engine parts that was sacrificial during the metal on metal contact and presented wear to key components, most notably cam to lifter

How does 15w-40 diesel oil work in gasoline engines ?

As long as it has high zddp it can be OK, so long as that thickness works for your climate. Engine weights do have temp bands where they operate well.

Can someone explain and recommend something cheaper ?

Buy a 2004 Honda civic or Honda accord, owning a classic/antique car isn't cheap. If you ever upgrade to a roller cam engine you can stop worrying about the zinc, but, that's expensive on its own and doesn't stop the fact these cars break

 

[vandyman]

Most of the hi mileage, extended life oils have zinc in them.
Castrol is one of them.

 

[Tynan918]

Unless they had a roller cam then you were causing wear in the engine.

Damn...

As long as it has high zddp it can be OK, so long as that thickness works for your climate. Engine weights do have temp bands where they operate well.

Gotcha 👍🏾...

Buy a 2004 Honda civic or Honda accord, owning a classic/antique car isn't cheap. If you ever upgrade to a roller cam engine you can stop worrying about the zinc, but, that's expensive on its own and doesn't stop the fact these cars break

🤣🤣🤣🤣🤣...don't think so... But a roller cam I will keep in mind when I do upgrade the cam.

Right now I'm just in a f'd up position and I needed the cheapest and best alternative route for oil... But I'm leaning on the Rotella 15w-30 diesel oil, because its $20 a gallon and already has zinc in it.

 

[Tynan918]

Most of the hi mileage, extended life oils have zinc in them.
Castrol is one of them.

Damn I didn't know that, high mileage is all I ever used before.

 

[olds307 and 403]

They claim the high mileage oils have more zinc, only partially true. A 5W30 or 10W30 can only have 800 ppm zinc and 900 ppm phos. A 5,10 or 15W40 can have more ZDDP, the 5,10,15 or 20W50 as well. That was SN, SP may be even less. New Diesel oils, like Rotella, only have a bit higher than that as well and have high detergent levels. Another option is conventional motorcycle oil, also has higher ZDDP. It is usually SL or SM rated, 10W40 would work well for any conditions a G body should be driven in. They don't have friction modifiers due to being used in wet clutches. I can get VR1 20W50 at Walmart as mid price oil. Do a half and half mix, to save money. My toy vehicles get an oil change, once a year. I plan on running our company's 5W30 Dexos approved, full synthetic truck rated oil at over $10 per liter once my Olds 350 is broke in.

 

[Clone TIE Pilot]

Damn...


Gotcha 👍🏾...



🤣🤣🤣🤣🤣...don't think so... But a roller cam I will keep in mind when I do upgrade the cam.

Right now I'm just in a f'd up position and I needed the cheapest and best alternative route for oil... But I'm leaning on the Rotella 15w-30 diesel oil, because its $20 a gallon and already has zinc in it.

That 15w30 is too thick and will increase wear which is the opposite of your goal. Engines wear most during cold starts which is why you want thin enough oil to start flowing immediately. The thicker the oil the slower it flows at cold start up. Once fully warmed up engines wear very little, the warmer the better to a point. I use 5w30 and add ZDDP to the jug and mix it around before pouring into the crankcase. Even 80's oil already had reduced ZDDP levels due to cat converters, but still higher than today's oils.