1970 Monte Carlo oil recommendation

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Originally Posted By: wtd
I read that the zinc content in one bottle is 5400ppm but I don't know for sure. I plan on checking at the John Deere dealership and see if they have anything in 10W-40.

If the 4T motorcycle oil you are referring to is made by Mobil, than thats a no go for me. I won't run Mobil anything in my vehicles anymore. Thanks for the input.

Wayne
4T is made by everybody. the hated autozone usually has it by Castrol, Valvoline and Mobil. Do some web searches on 4T motorcycle oil. Lawnmover oil is good too, like John Deere or MTD.
What's wrong with Mobil - the super 5000 is probably the best ILSAC conventional oil going now, IME (though not for your application). You need Moly and zddp to stave off cam and liner top wear
 
I'm still going to check out some other alternatives. I think a 10W-30 oil is out because that is what I tried running in it when it was newly rebuilt and the engine was noisier and the oil pressure was too low.

I did not have good luck with Mobil 1 years ago and even though Mobil probably has improved since then, I think there are better oils out there. I think Mobil oils are on the thin side and even today, I read about some of the complaints that I was experiencing back when I used it.

When I used it, my engine was noisy, it used more oil, and my oil analysis results did not justify me spending the money I was spending. I went back to a conventional oil and all three of the above complaints went away. Believe me, I was a long time Mobil 1 user and it was tough for me to switch away from it.

I will check out the other brands of 4T oil also as well as I have been looking at Amsoil since I have a farm account through them.

Wayne
 
Originally Posted By: wtd
I think a 10W-30 oil is out because that is what I tried running in it when it was newly rebuilt and the engine was noisier and the oil pressure was too low.
Wayne

Basing your oil viscosity selection on oil pressure is ideal.
What was the hot OP with the 30wt that you considered too low?
 
Originally Posted By: Trvlr500

+1 on getting that garbage out of the engine ASAP.


Garbage? No.. Just not ideal for that application. You may mail me any extra Havoline you don't want. (kidding).
 
Originally Posted By: CATERHAM
Originally Posted By: wtd
I think a 10W-30 oil is out because that is what I tried running in it when it was newly rebuilt and the engine was noisier and the oil pressure was too low.
Wayne

Basing your oil viscosity selection on oil pressure is ideal.
What was the hot OP with the 30wt that you considered too low?


If I remember right, at a hot idle in gear with 10W-30, I was between 10-15 psi which was lower than I was comfortable with. I believe that is still within GM's specs for these engines but I felt that was low for a newly rebuilt engine. Of course I didn't build it so I don't know if everything was done correctly or not.

With 10W-40, I'm at a little over the 25 mark.

I checked the John Deere 10W-30 oil that I have at home and its SM rated so I don't know if it has the reduced zinc levels in it. The straight 30 I have is SL rated though.

Wayne
 
Yes the additive pack in diesel is down, but its still has enough good stuff to work just fine. My cousin's 427 runs Rotella and he has had no issues with cam wear and that engine regularly sees over 6-7k RPM since he is running a 4:56 gear in the rear axle.
 
Originally Posted By: Robenstein
Yes the additive pack in diesel is down, but its still has enough good stuff to work just fine. My cousin's 427 runs Rotella and he has had no issues with cam wear and that engine regularly sees over 6-7k RPM since he is running a 4:56 gear in the rear axle.


Ditto. The requirements for diesel oils have changed, but their anti-wear additives today are still close to what passenger car oils had in the 1970s. Just check the Rotella UOA and VOA entries. The base oils are much better, of course, so I think they offer a "best of both worlds" solution. I've been running Rotella T5 10w30 blend lately with excellent results.
 
Originally Posted By: wtd
Originally Posted By: CATERHAM
Originally Posted By: wtd
I think a 10W-30 oil is out because that is what I tried running in it when it was newly rebuilt and the engine was noisier and the oil pressure was too low.
Wayne

Basing your oil viscosity selection on oil pressure is ideal.
What was the hot OP with the 30wt that you considered too low?


If I remember right, at a hot idle in gear with 10W-30, I was between 10-15 psi which was lower than I was comfortable with. I believe that is still within GM's specs for these engines but I felt that was low for a newly rebuilt engine. Of course I didn't build it so I don't know if everything was done correctly or not.

With 10W-40, I'm at a little over the 25 mark.

I checked the John Deere 10W-30 oil that I have at home and its SM rated so I don't know if it has the reduced zinc levels in it. The straight 30 I have is SL rated though.

Wayne


10-15 psi would make me nervous. Fully warmed idle on my LS1 GTO sees 27 psi on a thick 30w(M1 5w30+1qt 15w50). 10w40 looks like it is a good choice based on your pressure.

I also run 1oz(half bottle) of ZDDP Maxx. It might be overkill on stock roller setup, but the car is much quieter idling just boosting zinc to 1350ppm and phos to around 1250ppm.
 
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Yeah your warm idle oil pressure seems low to me. However, sometimes a bad sender can be the culprit. I had this happen on my Monte Carlo SS (1986). It said I had 30psi at a cold idle, and 10psi at a warm idle with 10w30. So I switched up to 10w40, and nothing changed. I finally switched the gauge sender and it went from 30 PSI at a cold idle to 50, and from 10psi at a warm idle to 30psi.

However if your builder used standard bearings and left the tolerances a bit on the loose side on the mains and rods, that could be a bit of the problem as well. But any good engine builder would just turn the crank, but I have seen it before.
 
Originally Posted By: wtd
Originally Posted By: CATERHAM
Originally Posted By: wtd
I think a 10W-30 oil is out because that is what I tried running in it when it was newly rebuilt and the engine was noisier and the oil pressure was too low.
Wayne

Basing your oil viscosity selection on oil pressure is ideal.
What was the hot OP with the 30wt that you considered too low?


If I remember right, at a hot idle in gear with 10W-30, I was between 10-15 psi which was lower than I was comfortable with. I believe that is still within GM's specs for these engines but I felt that was low for a newly rebuilt engine. Of course I didn't build it so I don't know if everything was done correctly or not.
With 10W-40, I'm at a little over the 25 mark.
I checked the John Deere 10W-30 oil that I have at home and its SM rated so I don't know if it has the reduced zinc levels in it. The straight 30 I have is SL rated though.
Wayne

Oil pressure on idle is not the most reliable indicator to judge whether an oil is too thin or thick as even 100 rpm can affect the OP reading noticeably. Comparing OP readings at elivated rev's (always at the same rpm) is more reliable I find.
For a Chevy, 50psi at 5,000 rpm is a good minimum.

As has been suggested Rotella 10W-30 is a pretty good heavy 30wt option (HTHS vis' 3.5cP) plus the benefit of Phos levels approaching 1100 ppm.
 
5W40 "Fleet Oils" such as Rotella T6 will be a synthetic although it is a Group III (Hydrocracked Petroleum) if your worried about seal concerns with a Group IV PAO Basestock (Although this was settled years ago).

Any off the shelf name brand 15W40 "Fleet Oil" will be a convetional. Shell Rotella T will be the most popular and easiest to find although nothing is wrong with Chevron Delo or Mobil Delvac is you happen to find them instead.
 
Originally Posted By: CATERHAM
Originally Posted By: wtd
I think a 10W-30 oil is out because that is what I tried running in it when it was newly rebuilt and the engine was noisier and the oil pressure was too low.
Wayne

Basing your oil viscosity selection on oil pressure is ideal.
What was the hot OP with the 30wt that you considered too low?
WTD:
I hope your engine builder didnt drill (too large) a cam chain oiler in the cam gallery plug.
 
I've got an aftermarket oil pressure gauge which actually uses oil in the lines up to the gauge itself. It is not an electric one. My pressures did go up when I used the heavier weight so I doubt the gauge is wrong.

As far as what the builder did when the engine was rebuilt, I have no idea. This engine was rebuilt in 1997 and I've only put like 15,000 miles or less since then. I don't remember what all was done or not done. I do remember that I was not too impressed with him at the time because he took forever to rebuild it and was doing it in his spare time.

I think he had the engine for like nine months and finally some friends and I went over there and basically took the engine because I was tired of waiting. The pistons, crank, and heads were on it but that was it. I had someone else finish putting it back together and I remember some of my parts and bolts were missing.

When this engine goes, its Big Block crate motor time.

Here are a few pics of the beast we are talking about.
014-2.jpg

013-1.jpg

015.jpg

and one of the car its in.
009-1.jpg


Anyway, I'm considering Amsoils AMO 10W-40 oil or one of the diesel oils for the next change. Thanks again to all of the input.

Wayne
 
That engine should have been/be able to run fine with 10w-30. If it does not, It was not rebuilt correctly. Oh, and get rid of that POS glass see through fuel filter, Its a fire waiting to happen!
 
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The engine probably wasn't built correctly or it wouldn't be running such low oil pressure. It will run on 10W-30, I just didn't like the oil pressure.

As far as the fuel filter goes, I probably will change it out but its been on the car for years with no problem. I can see the potential for problems though. I run that filter as well as the one in the carb because my gas tank is the original one and has a lot of [censored] that comes through the lines and the filter in the carb is not very big and would plug up pretty quick. I'll see about getting an enclosed metal one to replace the glass one.

When I first bought this car back in 1987, it had the factory 400 small block with headers and the headers were nothing but problems. After a few years of putting up with leaks, burnt plug wires, cooked starters, and long spark plug changes, I ditched the headers and went back to stock. Granted, I'm sure headers are better built and designed these days but the nightmares from years ago are still fresh in my mind.

The engine is not the factory one and this was originally a 400 small block car so what engine goes into the car is not very important. I was just thinking of going with a GM crate engine in the future because I have not found a reputable engine builder around here and from what I've read and been told, the GM crate engines are pretty good for the most part.

The other issue with this engine is that the machine shop screwed up on boring the block and bored it .60 over instead of .30 over. They thought it was a 402 which is a 396 .30 over so they bored it for that. Obviously they never measured the bore to begin with or they would have realized the mistake because I told them I only wanted it .30 and this engine did not have much wear in the cylinders at all. I probably didn't need it bored out at all as it only had 73,000 miles on it and was very clean inside. Anyway, the block cannot be bored out anymore so if it ever does need it done, its toast.

Thanks for the additional info.

Wayne
 
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I've looked at those but was thinking something along the lines of the 454 HO engine. I don't need anything too wild.

Wayne
 
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