Valvoline VR1 10w30 synthetic for stock rebuilt BBC GMC

[87567]

I have a rebuilt 1971 GMC 402 with 3000 miles on it. It is all stock with the flat tappet lifters. After break in, I ran Valvoline VR1 10w30 conventional for 3K miles. All seems ok. It used about a quart in 3K miles.

Switching now to the VR1 synthetic 10w30, but it is in winter storage. It will be a summer driver—so temp range from 50s-80s F for the most part.

Is this viscosity and oil choice adequate in your opinions? I will change about every 5k miles on mostly highway driving—sooner if looking dirty...

Thanks..

 

[ARCOgraphite]

Welcome!

What is it installed in? Truck? Stock or modified? What is the hot oil pressure at idle and 3000 rpm?

 

[RDY4WAR]

The appropriate oil grade/viscosity depends on 3 main factors...

1. Operating oil temp
2. Rod and main bearing clearance
3. The load on those bearings

Given it's a stock rebuild, the last one isn't a concern. If the rod and main bearings were installed at the factory clearance, between .0020-.0028", then a 30 grade is the appropriate grade. The operating oil temp is assumed to be 200-230°F for a street cruiser, given it sees long enough drives to fully warm up.

OEM replacement cams have very low intensity lobes and low spring rates that don't put a lot of force on the lifter/lobe interface. In many such cases, the 600-800 ppm ZDDP in common shelf oils has shown to be sufficient. However, I still recommend more just for peace of mind, especially since it's been rebuilt and who knows what the valvetrain geometry looks like compared to new, what the new springs rate is compared to stock, etc... best to run a good oil with more ZDDP just to be sure.

I think your application would like Mobil 1 FS Euro 0W-40. It has ~1000 ppm ZDDP so that's covered. The 0W-xx winter rating ensures good oil flow if you need to crank it in the dead of winter. It contains some group V base oil that'll help keep the engine clean. It's also surprisingly shear stable for the wide spread multi-grade. It can be had at Walmart for
If you want something better than what you can get off the shelf, there's High Performance Lubricants Bad Ass 5W-40 which is overkill for you but you'd never have to think twice about it. Red Line HP 0W-40 is also up there. Either of those oils you could change once a year, before putting away for winter storage, or 5,000-7,500 miles.

 

[87567]

Welcome!

What is it installed in? Truck? Stock or modified? What is the hot oil pressure at idle and 3000 rpm?

Hello, it is all stock except for headers and dynomax turbo mufflers with h pipe. I also switched to an edelbrock (1406) carb because the old quadrojet was not rebuildable. Running a new also stock turbo 350 tranny ( it should have the 400 I know, but was set up for a 350 and I went with it.)

No numbers on the oil pressure guage. It pegs the needle when cold idle, drops to about 5/8 on idle when warm, and is pretty much pegged at any rpm when warm..

Engine runs steady at about 200-205 degrees coolant temp at the heads...

Obviously, I’m concerned about ZDDP. That’s why I went with VR1. I’m not sure what to make of the blue dye....how can I expect the color to change as the oil is used do you think?

I don’t abuse it. I’m not doing burnouts or racing. Generally cruise in the right lane 55-60. I’m old and interested in longevity.

What would be a reasonable OCI with this oil be to start?

 

[87567]

Thanks on the Mobil1 suggestion. I actually prefer their products over Valvoline. I will consider that. The main reason I went with VR1 synthetic was for the ZDDP. I also want an affordable oil that is readily available.

BTW also running with WIX! Napa Gold, or Mobil1 filters. I always buy the bigger capacity long ones.

Oh, this is in a half ton, two wheel drive, long box...if that matters.

 

[RDY4WAR]

VR1 contains the same API SP base additive package as its common off-the-shelf Valvoline cousins. That means it also has a typical detergent additive content with a typical starting TBN so you can run it about the same interval. The conventional, I would change at 3,000-4,000 miles or 6 months. The synthetic version could go 5,000-6,000 miles or 1 year. Note: This is assuming the new carburetor is tuned for the proper air/fuel ratio with driving conditions and not running rich as those carbs can tend to do out of the box. Cruising at 12.0 AFR will introduce more fuel dilution to the crankcase and oil than a more appropriate 14.0 AFR.

What technical information do you have about the rebuild? Do you happen to have the grind/part number for the cam that was put in? What about valve springs? If it's something like an OEM replacement Melling cam, the amount in M1 FS 0W-40 would suffice, but just want to be sure.

 

[ARCOgraphite]

Hook up an aftermarket hydraulic gauge and check the oil pressure.. I don't like seeing that much OP. May need the pump changed or bypass spring adjusted. It its really pegging it will hurt the cam bearing and distributor drive,

And Ready4 has a good hint to get that AFB cal'd or get a Summit brand street /trip carb on there. Rich al the time is not good.

DO you have a AL aftermarket intake on there or a Q-jet to squarebore adapter? roval or oval heads?

 

[ARCOgraphite]

a stock #3874872 196/.398 cam is a dog. hope you got that cammed up just a little bit

 

[RDY4WAR]

I know someone running this engine in a Stock Eliminator. I'm betting his crankshaft alone cost more than this guy's total rebuild. It's bored .080" over for a 4.205" bore and using a Callies crank that's 3.773" stroke to make it a 419ci "stock" motor. The camshaft is insane with the stock .398"/.430" lift but dwells there for about 30 degrees with a .050" duration in the 270-280 range. I figure there's ~$40k in that "stock" engine. Stock heads, dual plane intake, spec'd Edelbrock 1901 carb, and turning 7200 rpm at the stripe.

 

[87567]

Ok....I don’t know the specs exactly. I got the truck from my father who had it done and he is no longer available for consultation. However, I know my dad and he never deviated from stock. All he ever wanted was OEM-period....

I can check the oil pressure and report, but I’m honestly not too concerned. That’s a 52 year old guage which was probably never accurate.....I know pressure is adequate. Coolant temp would seem to confirm that. I should check anyway...

Spent a lot of time on carb adjustments and tuning. Think I have it set right, but need to drive and test some more...

Still have original cast iron intake with the adapter for the edelbrock...

I am aware that this carb is actually too small for a big block. It flows only 650cfm. It’s all I could get here locally and should be ok...big blocks don’t like high revs—this should help prevent that....it would likely run out of fuel above 5k rpm.

Fellas, it is a truck. It’s not a hot rod. I’m more interested in torque than hp. I think current cam is fine for now....I haul stuff. I’m not racing anyone.

If and when I tear into it again, I will probably go roller cam—likely an rv or similar.

For now, I want to get my money out of it and want the best oil that’s practical...

 

[Greasymechtech]

Thanks on the Mobil1 suggestion. I actually prefer their products over Valvoline. I will consider that. The main reason I went with VR1 synthetic was for the ZDDP. I also want an affordable oil that is readily available.

BTW also running with WIX! Napa Gold, or Mobil1 filters. I always buy the bigger capacity long ones.

Oh, this is in a half ton, two wheel drive, long box...if that matters.

What Wix/M1 filter PN's?

If block/filter mount have a bypass valve, many ignorant builders used to block those to allow 100% always filtered oil flow, causing non-bypass filters to balloon, blow, or blow out or leak at the gasket. I've verify that the builder kept the stock OE built-in bypass if the filter doesn't have one.

You also have 5w40's at walmart which would be pretty good choices. Delo, Delvac, Mobil TDT or T&S, Rotella... are other options.
Mobil1 0w40 is an easy choice. 15w40 are even a choice for summer drivers, and 15w40 is also available in synthetic too.

The list from Ford is a good start too. You don't need full synthetic oil. Here is a good list of conventional, blends, and full synthetic in various grades. All have Ford's minimal 1000ppm P dosage requirement.

https://www.fcsdchemicalsandlubricants.com/additionalinfo/dieseloilsWSSM2C171F1.pdf

Another option, if cost/availability of VR1 synth is difficult, is to blend with it. With VR1's 1300ppm+ Z/P, and your engine is probably fine with normal API SP/GF6 ~800ppm oil, you could cut the VR1 with non-racing synth 50:50, still have the ~1000ppm peace of mind, and use less of the race oil.

 

[87567]

I did have the intake off at one point.....I honestly don’t remember if the heads were rival or oval....just don’t know...sorry.

Wix oil filter 51060xp
Mobil1 302a

I know who the builder was....I can ask about the bypass. They probably won’t know..

More important to get the actual oil pressure numbers. I will be able to check next week.

I’m not opposed to just using the Valvoline VR1 synthetic.....was hoping for verification that’s ok...

I do like the Mobil1 idea. I need to think on that a bit....I hesitate only because if it was built to 1971 OEM specs, that might be too thin...ok for newer spec motors....older....not so sure.

We always ran 10w30 or 10w 40 in Chevy v8s here....years and years...lnot unwilling to change, but need to think on it.

 

[RDY4WAR]

I did have the intake off at one point.....I honestly don’t remember if the heads were rival or oval....just don’t know...sorry.

Wix oil filter 51060xp
Mobil1 302a

I know who the builder was....I can ask about the bypass. They probably won’t know..

More important to get the actual oil pressure numbers. I will be able to check next week.

I’m not opposed to just using the Valvoline VR1 synthetic.....was hoping for verification that’s ok...

I do like the Mobil1 idea. I need to think on that a bit....I hesitate only because if it was built to 1971 OEM specs, that might be too thin...ok for newer spec motors....older....not so sure.

We always ran 10w30 or 10w 40 in Chevy v8s here....years and years...lnot unwilling to change, but need to think on it.

A 0W-40 is more viscous than a 5W-30 or 10W-30 until you get down to sub-zero temperatures. The 0W-xx winter rating doesn't thicken as much in extreme cold weather as the 5W-xx and 10W-xx oils do.

The first number doesn't represent the operating viscosity. It references the minimum temperature at which the oil is still pumpable (dynamic viscosity) with varying targets for each winter grade. Hence, the "W" stands for winter. (expressed in centipoise (cP))

0W-xx = -31°F (-35°C)
5W-xx = -22°F (-30°C)
10W-xx = -14°F (-25°C)
15W-xx = -6°F (-20°C)
20W-xx = 4°F (-15°C)

The second number is the actual oil grade at operating temperature. It's based on the kinematic (pouring) viscosity at 212°F. (expressed in centistoke (cSt))

xW-20 = 6.9 - 9.2 cSt (HTHS = ≥2.6 cP)
xW-30 = 9.3 - 12.4 cSt (HTHS = ≥2.9 cP)
xW-40 = 12.5 - 16.2 cSt (HTHS = ≥ 3.5 cP for 0W-40 and 5W-40 grades, ≥3.7 cP for 10W-40 and 15W-40)
xW-50 = 16.3 - 21.9 cSt (HTHS = ≥3.7 cP)

The HTHS is the high temp, high shear rating measured in dynamic viscosity at 150°C. Each grade has a minimum but no maximum.

A 0W-40 is required to be
A 10W-30 is required to be
The 0W-40 can withstand both lower temperature and higher temperature than the 10W-30 in most cases. Above ~10°C, the first number is largely irrelevant. There's other factors like shear stability, Noack volatility, etc... that comes into play with different grades, but that's a whole different can of worms.

 

[87567]

Ok. I get it. Thank you. The Mobil1 oil would be more versatile over a wider temperature range IF it has enough ZDDP.

From 50-90F, would it be better if the ZDDP is adequate? It won’t be driven at temps beyond either side of that range.

I checked oil pressure. It has 20 psi at idle when warm and 50 at 3,000 or so.

I think that is ok. It’s not running too rich....double checked the mixture....all is ok.

 

[Jetronic]

Mobil1 0W-40 FS has a higher than average ZDDP concentration. By quite a margin.

 

[High Performance Lubricants]

FS 0w40 is the best value on a retail shelf.

 

[Brons2]

I disagree with you guys about the 0w40.

The best value with high detergency and high-ish ZDDP will be an HDEO 10w30, for a mellow old BBC. 10w30 HDEO is only going to be marginally thinner than the Xw30 vs Xw40 indicates as 0W40 FS is a thin 40 and HDEO 10w30 will be a thick 30.

 

[Brons2]

If and when I tear into it again, I will probably go roller cam—likely an rv or similar.

These work pretty well for truck applications in my experience.

Xtreme Energy 200/206 Hydraulic Roller Cam for Chevrolet Big Block 396-454

Xtreme Energy 200/206 Hydraulic Roller Cam for Chevy Big Block 396-454. Excellent mileage, strong torque through RPM range. Smooth idle.

www.compcams.com

 

[87567]

Ok....just reporting back for the benefit of everyone....

I called Mobil customer assistance and specifically asked about the Euro 0W40. They did not recommend that oil for me. They said I should not do it. I asked why and only got the standard boilerplate response that it was not designed for this motor.

My next question was what do they recommend? After being on hold a minute, they told me they recommended Mobil 1 10w 30 high mileage for a 1971 5.7 liter engine....I reiterated that this is NOT a 5.7 liter. It is a 6.6-6.7 liter....(396-402). I asked again...(third time now asking the same question) Which Mobil 1 oil do they recommend? ....I was told they don’t offer a suitable product....

So straight from the manufacturer.....they said they have nothing for me....

I appreciate the sentiment, but I guess I will stick with the Valvoline VR1 synthetic.

 

[RDY4WAR]

I disagree with you guys about the 0w40.

The best value with high detergency and high-ish ZDDP will be an HDEO 10w30, for a mellow old BBC. 10w30 HDEO is only going to be marginally thinner than the Xw30 vs Xw40 indicates as 0W40 FS is a thin 40 and HDEO 10w30 will be a thick 30.

Mobil 1 FS 0W-40 has more detergents and as good or better TBN than most CK-4 HDMOs off the shelf. It also contains alkylated naphthalene which gives further wear protection, friction reduction, and cleaning ability. It also uses better base oils and is quite shear stable despite the wide multi-grade. The extra ZDDP is icing on the cake, something a few HDMOs no longer have. I would pick M1 FS 0W-40 over any off the shelf CK-4 HDMO any day of the week.