CHEVY Is Oil Additives worth it, on a high mileage SBC?

[g0thiac]

Both my Bonneville and Caprice are approaching high mileage on their engines.

I've heard something like Marvel Mystery Oil is good to add, is this true? I've already used Seafoam in the carburetors, which has helped decently.

Thanks!

 

[69hurstolds]

If you don't mind pi ssing your money away, sure. Go for it.

While an STP treatment or mystery whatever the f*ck oil may temporarily hide a symptom for a bit, the problem is still there. Never been a fan of band-aids except in an emergency. Thus your real fix is getting another SBC, building it or already built, whatever, and swap it in, or rebuild what you have. Problem instantly goes away for at least a long time, hopefully. And don't buy any SBC from the same guy who sold you your Pontiac.

Use a good, quality oil, filters, and fluids, and keep the engine tuned as best you can. Fix any and all vacuum leaks. This may take time, but it's worth it if you want to maximize longevity of what you have left in those engines. There's no magic pill for high-miles. Doesn't mean it's automatically on its last legs, but I got a feeling those engines you have may not have been cared for all that well in previous lives.

 

[g0thiac]

If you don't mind pi ssing your money away, sure. Go for it.

While an STP treatment or mystery whatever the f*ck oil may temporarily hide a symptom for a bit, the problem is still there. Never been a fan of band-aids except in an emergency. Thus your real fix is getting another SBC, building it or already built, whatever, and swap it in, or rebuild what you have. Problem instantly goes away for at least a long time, hopefully. And don't buy any SBC from the same guy who sold you your Pontiac.

Use a good, quality oil, filters, and fluids, and keep the engine tuned as best you can. Fix any and all vacuum leaks. This may take time, but it's worth it if you want to maximize longevity of what you have left in those engines. There's no magic pill for high-miles. Doesn't mean it's automatically on its last legs, but I got a feeling those engines you have may not have been cared for all that well in previous lives.

Well, it's not so much to temporarily fix anything, it's more so for longevity reasons.

And trust me, I wouldn't even go near the guy who sold me the Pontiac, I'd probably do something really dumb and end up in jail for violating my probation.

The Caprice I'm mainly focused on, because it was taken care of very well, since I bought it straight from a mechanic out of a shop, who owned it since '04.

I'll definitely take a look at the vacuum hoses, but as for fluids, I've always gotten top quality products 😀

So if it's just doing the obvious and basic maintenance, then it should be no problem. I just wanted to take any extra initiative possible. Thanks.

 

[ck80]

The better question is if you are using CORRECT motor oil itself with proper ZDDP concentrations so you don't wipe a cam and send metal bits all through your engine.

Almost all current oil does not meet certification requirements for flat tappet cam motors.

I doubt either your bonny or caprice are running roller lifters/camshaft.

 

[Clone TIE Pilot]

MMO is good for cleaning up sticky lifters and valves in engines that sit around for long periods of time. Any engine can develop morning sickness if it sits around for a long time like sitting over the winter waiting for the Spring rains to wash the road salt away. Antique tractor guys really like MMO. However, it won't cure true mechanical problems, just varnish build up.

 

[MrSony]

Recently discovered Napa has 5 quart jugs non synthetic for $11.99, add lucas zddp and a filter you can do it for under $40.

Flat tappets need zinc. Dont run thick oil like 20w50 to hide problems. It will just make the pump work harder. If you cant get good pressure (if you have gauges) with stock reccomended weight oil it's not long for this world.

 

[MrSony]

Pop a valve cover. If it's cleanish under there and on the heads odds are it was either taken care of maintenece wise or was recently rebuilt. Mmo as said is typically used to free up sticky rings and lifters and what not. You can try it but do it right before an oil change. Dump some in, idle it about 20 min, rev it up a bit, let cool and drain.

 

[g0thiac]

The better question is if you are using CORRECT motor oil itself with proper ZDDP concentrations so you don't wipe a cam and send metal bits all through your engine.

Almost all current oil does not meet certification requirements for flat tappet cam motors.

I doubt either your bonny or caprice are running roller lifters/camshaft.

I use 10w-30 oil, according to the manual. And from what I've read, V8's past '87, in cars at least, used roller cams. But I could be mistaken.

 

[g0thiac]

MMO is good for cleaning up sticky lifters and valves in engines that sit around for long periods of time. Any engine can develop morning sickness if it sits around for a long time like sitting over the winter waiting for the Spring rains to wash the road salt away. Antique tractor guys really like MMO. However, it won't cure true mechanical problems, just varnish build up.

That's what I'm getting at here, since my vehicles are being stored for now. Thanks.

 

[g0thiac]

Pop a valve cover. If it's cleanish under there and on the heads odds are it was either taken care of maintenece wise or was recently rebuilt. Mmo as said is typically used to free up sticky rings and lifters and what not. You can try it but do it right before an oil change. Dump some in, idle it about 20 min, rev it up a bit, let cool and drain.

Good idea, I will when the weather gets warmer, thanks!