[DT]

With all the information floating around about oil, what is best, what viscosity etc, etc, I thought a poll would be a good idea to see what most guys are using ?? 5w30, 10w30, 10w40, 20w50 etc...

[72LS3Z27]

Picked 5-30.Its a new crate motor and gm recommends it for it.
So,off the shelf 5-30 for me,with the zinc additve added in.

[DT]

Originally Posted by 72LS3Z27

Picked 5-30.Its a new crate motor and gm recommends it for it.
So,off the shelf 5-30 for me,with the zinc additve added in.

Thanks Chris. Just an FYI here. It is reported that adding anything to the oil reduces the protection ability. Again, this is one of those topics where you ask 10 guys and you will get 10 different answers. From what I read, its a NO, NO.

[DjD]

It's not about what most guys are using, it's about the engine and what it requires due to assembly tolerances and components selection... If in doubt what to use, check with your engine builder or the manufacture if it's a crate engine...

[72LS3Z27]

Originally Posted by DT

Thanks Chris. Just an FYI here. It is reported that adding anything to the oil reduces the protection ability. Again, this is one of those topics where you ask 10 guys and you will get 10 different answers. From what I read, its a NO, NO.

Aint that the truth,lol.Especially where oil and or filters are being discussed.
But I will stop adding the zinc when the oil manufacturers are allowed to put it back in.

[DT]

Originally Posted by DjD

It's not about what most guys are using, it's about the engine and what it requires due to assembly tolerances and components selection... If in doubt what to use, check with your engine builder or the manufacture if it's a crate engine...

Dennis understood, but do you really know what tolerances you have and what componets are in your engine? Not everyone does. What if you do not have an engine builder or a crate engine ?? A crate engine is one thing, an engine builder is another. I bet if you ask several engine builders this question, you will get several different answers LOL. Most of our engines are pretty much the same, most. (musclecar era)

[DjD]

Originally Posted by DT

Dennis understood, but do you really know what tolerances you have and what componets are in your engine? Not everyone does. What if you do not have an engine builder or a crate engine ?? A crate engine is one thing, an engine builder is another. I bet if you ask several engine builders this question, you will get several different answers LOL. Most of our engines are pretty much the same, most. (musclecar era)

By the time an engine has been through about 3 owners I can see the spec's being lost and someone not knowing what's in their engine so I'd recommend asking the previous owner what oil they used... If you spend much time reading engine and performance posts you'll see a good majority know what makes their engine tic... As for builder, I know several and they don't build anything alike, one guy totally old school/racing with loose bearing clearances and he'll tell you use something with a 50 in it... On the other side I also know a builder that likes tight clearances and he'll tell you use 5w30. The guy that built my engine is right in the middle, I run 10w40 or 15w40.

On top of that there are hyd and solid cams, hyd roller and solid roller cams as well and what you use may depend on how much zinc is in the oil...

If you don't know what's inside your engine then start with a 10w30 and check your oil pressure, next use a 10w40 especially watch cold pressure as the rpms come up...

I'm not trying to sound like a know it all or shoot down the survey but if you get 50 replies and 50% run 5w30 because they have ls1 or other modern engines and you have a 100k mile 350 built in 1980 with stock GM parts and an aftermarket non-roller cam you are not going to like the results if you fill your crank case with 5w30 because of the survey results...

[camaroman7d]

Pretty much agree with Dennis.

Simple answer is to let your oil pressure gauge tell you what the engine wants. This applies even if you have no idea what the tolerances started off as. The general rule of thumb has been 10psi of oil pressure per 1000RPM.

When you throw oil pumps differences in there two engines with the same clearances could have very different oil pressures with the same oil.

Still nothing wrong with the poll, It's only a matter of time before five forty shows up, just watch, I think he searches the sites for anything oil related. I also suspect someone is fishing for him.

[DT]

I absolutely agree Dennis. I was just hoping for a simple survey comprised of average guys with the typical 327, 350, 396 or even the 454 engine. I know there could be many variables here, none the less I was just curious what the numbers would show. Thanks.

[67 Plum]

10w40 Rotella in my 400. Tractor Supply had Shell Rotella on the shelf from when they opened the local store. 2001 date on the yellowed bottles. Bought all they had a few years ago.Have 6 bottles left.

[DT]

Originally Posted by 67 Plum

10w40 Rotella in my 400. Tractor Supply had Shell Rotella on the shelf from when they opened the local store. 2001 date on the yellowed bottles. Bought all they had a few years ago.Have 6 bottles left.

Nice

[Steiner]

On the new hydraulic roller cam 400 built a few years ago, 10W-40 Summit Racing conventional for the first two changes. Oil analyses came back beautiful.
Now on 10W-40 Summit Racing semi-synthetic and about ready to send some of it off for analysis.

On the solid lifter 327 that came in the other car, initially went with 10W-40 Summit Racing but found out the previous owner's helicoil job on the oil pan didn't work too good so it wouldn't stop leaking. Drained it and was going to reuse it after putting a new oil pan on but flakes of ceramic fell off the crappy headers on it into the drain pan. Went with Shell Rotella T6 5W-40 full synthetic and a half bottle of ZDDPlus. Sent a virgin sample of the T6 off and it was already at 1250ppm zinc.

Will most likely go to the T6 5W-40 with no additives in the 400 soon.

[DT]

I would love to know the analysis of the 10W40 Summit semi-synthetic. Is this the oil made by Spectro?? Thanks

[Steiner]

Originally Posted by DT

I would love to know the analysis of the 10W40 Summit semi-synthetic. Is this the oil made by Spectro?? Thanks

Yeah, that' it. I reckon they stopped having it made for them last year. Gotta check mileage but pretty sure it'll be ready to come out this weekend and Blackstone usually has the anaysis done within a week of it being mailed out.

[DT]

Great, I have about 6 quarts left. Thanks