just switch brands and be done with it, you can mix, but WHY????? to each his own however....do whatever floats your boat. good luck

 

Have you ck'd it with a real gauge just to be sure?


JIM

 

Huh? What? Who?..................Now you’ve done it. You've gone and woke me up. So here goes.

You've gotten some good advice here. And I'll also say to just stay with your 10W30. You do not want to go thicker. For more details, read on if you dare.

To learn about motor oil, most folks just talk to their buddies, read a few Forum threads here or there, maybe read a general Internet article on oil. Then they figure they know all there is to know about motor oil. But, a large percentage of Hotrodders and Racers use 20W50, which shows they really don’t know very much at all about motor oil. If they did, they would never run such thick oil.

If you ask 20 different people the same motor oil question, you’ll almost certainly get 20 different answers. But of course there cannot be 20 correct answers to a single question, which also shows that most people are largely clueless when it comes to motor oil.

Some of you might recall that I’ve written a number of motor oil threads and replies to motor oil discussions over the past year, where I’ve also talked about the benefits of using thinner oil, and the fact that lower ZDDP levels in modern API certified oil is NOT a concern. A motor oil’s ability to prevent wear is determined by its base oil and its additive package’s extreme pressure anti-wear components “as a whole”, and NOT simply by the level of ZDDP present. Modern API certified street oils use alternate chemistry that is equal to or better than zinc. There is nothing magical about zinc, it has simply been usable, available and affordable. But, it fouls cats and needs to be reduced for use in newer cat equipped vehicles. Even the High Powered Supercharged Corvettes use modern low zinc API certified oils.

But, many of the replies I’ve gotten back from my threads and my responses have been from people wanting to argue against the facts, even when they really don’t know much at all about motor oil. They just want to follow common wives tales, and they only shoot themselves in the foot by wanting to argue rather than learn the facts.

In any case, the benefits of using thinner oil are:

• Quicker flow at cold start-up to begin lubricating vital engine components much more quickly than thicker oil can.

• More flow at normal operating temperatures. And oil flow is lubrication, oil pressure is NOT. Oil pressure is only a measurement of resistance to flow. Of course you need enough oil pressure to move the oil, but oil pressure in and of itself, is NOT what you are after. Running thicker oil just to up the oil pressure is the wrong thing to do, because that only reduces flow and all the benefits that come along with flow.

• The old rule of thumb of 10 psi for every 1,000 rpm is perfectly fine. Any more pressure than that and you are losing flow for no good reason. It is best to run the thinnest oil you can, that will maintain the rule of thumb oil pressure.

• Oil flow is what carries heat away from vital engine components. Engine components are directly oil cooled, but only indirectly water cooled. If you run thicker oil, you will be driving up engine component temps and reducing lubrication.

• Thinner oil will increase HP because of less viscous drag, compared to thicker oils.

• Almost no one should ever need to run oil thicker than a multi-viscosity 30 weight. The lower the first number cold viscosity rating, the better the cold flow. For example, 0W30 flows WAY better cold than straight 30wt, which is horrible for cold start-up flow and should be avoided at all cost. And the lower the second number hot viscosity rating, the better the hot flow. For example, 0W30 flows WAY better hot than 20W50.

And regarding ZDDP levels, as mentioned above, that is NOT what you care about, because that does NOT determine an oil’s wear protection capability. What you care about is “load carrying capacity/film strength”. Because that is all you have working for you as you near metal to metal contact and the wear/damage and/or failure that can follow. The fact is, ZDDP levels and “load carrying capacity/film strength”, may or may not go together. You have to perform real world wear protection capability testing, in the form of friction testing under load, at operating temperature, to determine how well various motor oils protect against wear. And that is precisely what I’ve done over the past year.

Also keep in mind, that the higher the film strength, the less wear you will have during cold start-up (where most wear takes place due to a lack of oil on components), when all you have present is a film of oil. And of course any time you only have a film of oil at operating temperature, such as at a flat tappet/lobe interface, the higher the film strength, the better the wear protection.

If you have oil thicker than a mere film, it becomes “liquid” oil. And liquids cannot be compressed. That of course is how hydraulics work. So, “any” and I mean “any” motor oil, no matter if it costs $1.00 per quart or $20.00 per quart, will provide the exact same wear protection capability when in “liquid” form, since it cannot be compressed. And if it gets pushed out of the way, you are left with only an oil film, and the need for a high level of “load carrying capacity/film strength” to provide the best protection against wear.

As mentioned, I’ve performed extensive wear testing over the past year. And as you will see below, zinc levels, viscosity, synthetic or conventional oil, are not what determines an oil’s wear protection capability. The base oil and its additive package “as a whole” is what determines that. Here is the “load carrying capacity/film strength” ranking list from all that testing (the higher the psi, the better the protection).

1. 5W30 Pennzoil Ultra, API SM synthetic = 115,612 psi
I have not been able to find this oil with the latest API SN certification. The bottle says, “No leading synthetic oil provides better wear protection”. For once, a product’s hype turns out to be true.
zinc = 806 ppm
phos = 812 ppm
moly = 66 ppm

2. “USED” 5W20 Castrol Edge with Titanium, API SN with 5,000 miles on it = 107,391 psi
zinc = 791 ppm (down 251 ppm or down 24% from new)
phos =643 ppm (down 214 ppm or down 25% from new)
moly = 67 ppm (down 33 ppm or down 33% from new)
titanium = 36 ppm (down 13 ppm or down 27% from new)
total anti-wear = 1537 ppm (down 511 ppm or down 25% from new)

The 107,391 psi wear protection capability shown here, is a 7% “higher” wear protection capability with this batch of “used” oil, compared to the original “new” test oil batch. Repeat testing of both the used batch of oil and the original new batch of oil, resulted in consistent and repeatable results for each batch. So, the wear protection capability psi value shown here is correct.

This oil did NOT lose any wear protection capability, even though the zinc and the other anti-wear component levels have dropped SIGNIFICANTLY. That is because the zinc level does NOT matter, as long as you don’t run out of it. Zinc becomes depleted over time without having any affect on wear protection. So, more zinc only provides “longer” wear protection, but NOT “more” wear protection. These results also show that the normal practice of testing brand new oil is representative of what you can expect as the oil accumulates miles, since the used oil’s wear protection capability does not drop.

3. 10W30 Lucas Racing Only synthetic = 106,505 psi
zinc = 2642 ppm
phos = 3489 ppm
moly = 1764 ppm
NOTE: This oil is suitable for short term racing use only, and is not suitable for street use.

4. 5W30 Mobil 1, API SN synthetic = 105,875 psi
zinc = 801 ppm
phos = 842 ppm
moly = 112 ppm

5. 0W30 Amsoil Signature Series 25,000 miles, API SN synthetic = 105,008 psi
zinc = 824 ppm
phos = 960 ppm
moly = 161 ppm


6. 10W30 Valvoline NSL (Not Street Legal) Conventional Racing Oil = 103,846 psi
zinc = 1669 ppm
phos = 1518 ppm
moly = 784 ppm
NOTE: This oil is suitable for short term racing use only, and is not suitable for street use.

7. 5W50 Motorcraft, API SN synthetic = 103,517 psi
zinc = 606 ppm
phos = 742 ppm
moly = 28 ppm

8. 10W30 Valvoline VR1 Conventional Racing Oil (silver bottle) = 103,505 psi
zinc = 1472 ppm
phos = 1544 ppm
moly = 3 ppm

9. 10W30 Valvoline VR1 Synthetic Racing Oil, API SL (black bottle) = 101,139 psi
zinc = 1180 ppm
phos = 1112 ppm
moly = 162 ppm

10. 5W30 Chevron Supreme, API SN conventional = 100,011 psi
This one only costs $4.29 per quart at the Auto Parts Store where I bought it.
zinc = 1018 ppm
phos = 728 ppm
moly = 161 ppm

11. 5W20 Castrol Edge with Titanium, API SN synthetic = 99,983 psi
zinc = 1042 ppm
phos = 857 ppm
moly = 100 ppm
titanium = 49 ppm

12. 20W50 Castrol GTX ,API SN conventional = 96,514 psi
zinc = 610 ppm
phos = 754 ppm
moly = 94 ppm

13. 30 wt Red Line Race Oil synthetic = 96,470 psi
zinc = 2207 ppm
phos = 2052 ppm
moly = 1235 ppm
NOTE: This oil is suitable for short term racing use only, and is not suitable for street use.

14. 0W20 Mobil 1 Advanced Fuel Economy, API SN synthetic = 96,364 psi
zinc = 742 ppm
phos = 677 ppm
moly = 81 ppm

15. 5W30 Quaker State Ultimate Durability, API SN synthetic = 95,920 psi
zinc = 877 ppm
phos = 921 ppm
moly = 72 ppm

16. 5W30 Castrol Edge with Titanium, API SN synthetic = 95,717 psi
zinc = 818 ppm
phos = 883 ppm
moly = 90 ppm
titanium = 44 ppm

17. 10W30 Joe Gibbs XP3 NASCAR Racing Oil synthetic = 95,543 psi
zinc = 743 ppm
phos = 802 ppm
moly = 1125 ppm
NOTE: This oil is suitable for short term racing use only, and is not suitable for street use.

18. 5W20 Castrol GTX, API SN conventional = 95,543 psi
zinc = TBD
phos = TBD
moly = TBD
NOTE: Oil numbers 17 and 18 were tested weeks apart, but due to the similarities in their wear scar sizes, their averages ended up the same.

19. 5W30 Castrol GTX ,API SN conventional = 95,392 psi
zinc = 830 ppm
phos = 791 ppm
moly = 1 ppm

20. 10W30 Amsoil Z-Rod Oil synthetic = 95,360 psi
zinc = 1431 ppm
phos = 1441 ppm
moly = 52 ppm

21. 5W30 Valvoline SynPower, API SN synthetic = 94,942 psi
zinc = 969 ppm
phos = 761 ppm
moly = 0 ppm

22. 5W30 Valvoline Premium Conventional, API SN = 94,744 psi
zinc = TBD
phos = TBD
moly = TBD

23. 5W20 Mobil 1, API SN synthetic = 94,663 psi
zinc = 764 ppm
phos = 698 ppm
moly = 76 ppm

24. 5W20 Valvoline SynPower, API SN synthetic = 94,460 psi
zinc = 1045 ppm
phos = 742 ppm
moly = 0 ppm


25. 5W30 Lucas, API SN conventional = 92,073 psi
zinc = 992 ppm
phos = 760 ppm
moly = 0 ppm

26. 5W30 O'Reilly (house brand), API SN conventional = 91,433 psi
This one only costs $3.99 per quart at the Auto Parts Store where I bought it.
zinc = 863 ppm
phos = 816 ppm
moly = 0 ppm

27. 5W30 Maxima RS530 Synthetic Racing Oil = 91,162 psi
zinc = 2162 ppm
phos = 2294 ppm
moly = 181 ppm

28. 5W30 Red Line, API SN synthetic = 91,028 psi
zinc = TBD
phos = TBD
moly = TBD

29. 5W20 Royal Purple API SN synthetic = 90,434 psi
zinc = 964 ppm
phos = 892 ppm
moly = 0 ppm

30. 10W30 Quaker State Defy, API SL semi-synthetic = 90,226 psi
zinc = 1221 ppm
phos = 955 ppm
moly = 99 ppm

31. 5W20 Valvoline Premium Conventional, API SN = 90,144 psi
zinc = TBD
phos = TBD
moly = TBD


32. 30 wt Castrol Heavy Duty, API SM conventional = 88,089 psi
zinc = 907 ppm
phos = 829 ppm
moly = 56 ppm

33. 20W50 LAT Synthetic Racing Oil, API SM = 87,930 psi
zinc = TBD
phos = TBD
moly = TBD

34. 10W30 Joe Gibbs HR4 Hotrod Oil synthetic = 86,270 psi
zinc = 1247 ppm
phos = 1137 ppm
moly = 24 ppm

35. 5W20 Pennzoil Ultra, API SM synthetic = 86,034 psi
I have not been able to find this oil with the latest API SN certification.
zinc = TBD
phos = TBD
moly = TBD

36. 15W40 RED LINE Diesel Oil synthetic, API CJ-4/CI-4 PLUS/CI-4/CF/CH-4/CF-4/SM/SL/SH/EO-O = 85,663 psi
zinc = 1615 ppm
phos = 1551 ppm
moly = 173 ppm

37. 5W30 Royal Purple API SN synthetic = 84,009 psi
zinc = 942 ppm
phos = 817 ppm
moly = 0 ppm

38. 20W50 Royal Purple API SN synthetic = 83,487 psi
zinc = 588 ppm
phos = 697 ppm
moly = 0 ppm

39. 20W50 Kendall GT-1 High Performance with liquid titanium, API SN conventional = 83,365 psi
zinc = 991 ppm
phos = 1253 ppm
moly = 57 ppm
titanium = 84 ppm

40. 5W30 Mobil 1 Extended Performance 15,000 mile, API SN synthetic = 83,263 psi
zinc = 890 ppm
phos = 819 ppm
moly = 104 ppm

41. 0W20 Castrol Edge with Titanium, API SN synthetic = 82,867 psi
zinc = TBD
phos = TBD
moly = TBD

42. 5W30 LAT Synthetic Racing Oil, API SM = 81,800 psi
zinc = 1784 ppm
phos = 1539 ppm
moly = 598 ppm


43. 15W40 ROYAL PURPLE Diesel Oil synthetic, API CJ-4 /SM, CI-4 PLUS, CH-4, CI-4 = 76,997 psi
zinc = TBD
phos = TBD
moly = TBD

44. 5W30 Lucas API SM synthetic = 76,584 psi
zinc = 1134 ppm
phos = 666 ppm
moly = 0 ppm

45. 5W30 GM's AC Delco dexos 1 API SN semi-synthetic = 76,501 psi
zinc = 878 ppm
phos = 758 ppm
moly = 72 ppm

46. 5W50 Castrol Edge with Syntec API SN, synthetic, formerly Castrol Syntec, black bottle = 75,409 psi
zinc = 1252 ppm
phos = 1197 ppm
moly = 71 ppm


47. 5W30 Royal Purple XPR (Extreme Performance Racing) synthetic = 74,860 psi
zinc = 1421 ppm
phos = 1338 ppm
moly = 204 ppm

48. 5W40 MOBIL 1 TURBO DIESEL TRUCK synthetic, API CJ-4, CI-4 Plus, CI-4, CH-4 and ACEA E7 = 74,312 psi
zinc = 1211 ppm
phos = 1168 ppm
moly = 2 ppm

49. 15W40 CHEVRON DELO 400LE Diesel Oil, conventional, API CJ-4, CI-4 Plus, CH-4, CF-4,CF/SM, = 73,520 psi
zinc = 1519 ppm
phos = 1139 ppm
moly = 80 ppm

50. 15W40 MOBIL DELVAC 1300 SUPER Diesel Oil conventional, API CJ-4, CI-4 Plus, CI-4, CH-4/SM, SL = 73,300 psi
zinc = 1297 ppm
phos = 1944 ppm
moly = 46 ppm

51. 15W40 Farm Rated Heavy Duty Performance Diesel Oil conventional CI-4, CH-4, CG-4, CF/SL, SJ = 73,176 psi
zinc = 1325ppm
phos = 1234 ppm
moly = 2 ppm

52. 15W40 SHELL ROTELLA T Diesel Oil conventional, API CJ-4, CI-4 Plus, CH-4, CF-4,CF/SM = 72,022 psi
zinc = 1454 ppm
phos = 1062 ppm
moly = 0 ppm

53. Brad Penn, Penn Grade 1 Nitro 70 Racing Oil semi-synthetic = 72,003 psi
zinc = TBD
phos = TBD
moly = TBD

54. 0W30 Brad Penn, Penn Grade 1 semi-synthetic = 71,377 psi
zinc = 1621 ppm
phos = 1437 ppm
moly = 0 ppm

55. 15W40 “OLD” SHELL ROTELLA T Diesel Oil conventional, API CI-4 PLUS, CI-4, CH-4,CG-4,CF-4,CF,SL, SJ, SH = 71,214 psi
zinc = 1171 ppm
phos = 1186 ppm
moly = 0 ppm

56. 10W30 Brad Penn, Penn Grade 1 semi-synthetic = 71,206 psi
zinc = 1557 ppm
phos = 1651 ppm
moly = 3 ppm

57. 15W40 VALVOLINE PREMIUM BLUE HEAVY DUTY DIESEL Oil conventional, API CJ-4, CI-4 Plus, CI-4, CH-4, CG-4, CF-4, CF/SM = 70,869 psi
zinc = TBD
phos = TBD
moly = TBD

58. 15W50 Mobil 1, API SN synthetic = 70,235 psi
zinc = 1,133 ppm
phos = 1,168 ppm
moly = 83 ppm

59. 5W40 CHEVRON DELO 400LE Diesel Oil synthetic, API CJ-4, CI-4 Plus, CI-4, SL, SM = 69,631 psi
zinc = TBD
phos = TBD
moly = TBD

60. 30wt Edelbrock Break-In Oil conventional = 69,160 psi
zinc = 1545 ppm
phos = 1465 ppm
moly = 4 ppm

61. 5W30 Motorcraft, API SN synthetic = 68,782 psi
zinc = 796 ppm
phos = 830 ppm
moly = 75 ppm

62. 10W40 Edelbrock synthetic = 68,603 psi
zinc = 1193 ppm
phos = 1146 ppm
moly = 121 ppm
This oil is manufactured for Edelbrock by Torco.


63. 5W40 SHELL ROTELLA T6 Diesel Oil synthetic, API CJ-4, CI-4 Plus, CI-4, CH-4, SM, SL = 67,804 psi
zinc = TBD
phos = TBD
moly = TBD

64. 15W40 LUCAS MAGNUM Diesel Oil, conventional, API CI-4,CH-4, CG-4, CF-4, CF/SL = 66,476 psi
zinc = 1441 ppm
phos = 1234 ppm
moly = 76 ppm

65. 15W40 CASTROL GTX DIESEL Oil conventional, API CJ-4, CI-4 Plus, CI-4, CH-4, CG-4, CF-4/SN = 66,323 psi
zinc = TBD
phos = TBD
moly = TBD

66. 10W30 Royal Purple HPS (High Performance Street) synthetic = 66,211 psi
zinc = 1774 ppm
phos = 1347 ppm
moly = 189 ppm

67. 10W40 Valvoline 4 Stroke Motorcycle Oil, API SJ conventional = 65,553 psi
zinc = 1154 ppm
phos = 1075 ppm
moly = 0 ppm

68. 5W30 Klotz Estorlin Racing Oil, API SL synthetic = 64,175 psi
zinc = 1765 ppm
phos = 2468 ppm
moly = 339 ppm

69. “ZDDPlus” added to Royal Purple 20W50, API SN, synthetic = 63,595 psi
zinc = 2436 ppm (up 1848 ppm)
phos = 2053 ppm (up 1356 ppm)
moly = 2 ppm (up 2 ppm)

The psi value here is 24% LOWER than this oil had BEFORE the ZDDPlus was added to it. Oil companies always say to NEVER add anything to their oils, because adding anything will upset the carefully balanced additive package, and ruin the oil’s chemical composition. And that is precisely what we see here. Adding ZDDPlus SIGNIFICANTLY REDUCED this oil’s wear prevention capability. Just the opposite of what was promised. Buyer beware.

70. Royal Purple 10W30 Break-In Oil conventional = 62,931 psi
zinc = 1170 ppm
phos = 1039 ppm
moly = 0 ppm

71. 10W30 Lucas Hot Rod & Classic Hi-Performance Oil, conventional = 62,538 psi
zinc = 2116 ppm
phos = 1855 ppm
moly = 871 ppm

72. 0W20 Klotz Estorlin Racing Oil, API SL synthetic = 60,941 psi
zinc = TBD
phos = TBD
moly = TBD

73. 10W30 Comp Cams Muscle Car & Street Rod Oil, synthetic blend = 60,413 psi
zinc = 1673 ppm
phos = 1114 ppm
moly = 67 ppm


74. 10W40 Torco TR-1 Racing Oil with MPZ conventional = 59,905 psi
zinc = 1456 ppm
phos = 1150 ppm
moly = 227 ppm

75. 10W40 Edelbrock conventional = 59,120 psi
zinc = TBD
phos = TBD
moly = TBD
This oil is manufactured for Edelbrock by Torco.


76. 0W20 LAT Synthetic Racing Oil, API SM = 57,228 psi
zinc = TBD
phos = TBD
moly = TBD


77. “ZDDPlus” added to O’Reilly (house brand) 5W30, API SN, conventional = 56,728 psi
zinc = 2711 ppm (up 1848 ppm)
phos = 2172 ppm (up 1356 ppm)
moly = 2 ppm (up 2 ppm)

The psi value here is a whopping 38% LOWER than this oil had BEFORE the ZDDPlus was added to it. Adding ZDDPlus SIGNIFICANTLY REDUCED this oil’s wear prevention capability. Just the opposite of what was promised. Buyer beware.


78. “ZDDPlus” added to Motorcraft 5W30, API SN, synthetic = 56,243 psi
zinc = 2955 ppm (up 1848 ppm)
phos = 2114 ppm (up 1356 ppm)
moly = 76 ppm (up 2 ppm)

The psi value here is 12% LOWER than this oil had BEFORE the ZDDPlus was added to it. Adding ZDDPlus SIGNIFICANTLY REDUCED this oil’s wear prevention capability. Just the opposite of what was promised. Buyer beware.

79. “Edelbrock Zinc Additive” added to Royal Purple 5W30, API SN, synthetic = 54,044 psi
zinc = 1515 ppm (up 573 ppm)
phos = 1334 ppm (up 517 ppm)
moly = 15 ppm (up 15 ppm)

The psi value here is a whopping 36% LOWER than this oil had BEFORE the Edelbrock Zinc Additive was added to it. Adding Edelbrock Zinc Additive SIGNIFICANTLY REDUCED this oil’s wear prevention capability. Just the opposite of what was promised. Buyer beware.

80. 10W30 Comp Cams Break-In Oil conventional = 51,749 psi
zinc = 3004 ppm
phos = 2613 ppm
moly = 180 ppm

81. “Edelbrock Zinc Additive” added to Lucas 5W30, API SN, conventional = 51,545 psi
zinc = 1565 ppm (up 573 ppm)
phos = 1277 ppm (up 517 ppm)
moly = 15 ppm (up 15 ppm)

The psi value here is a “breath taking” 44% LOWER than this oil had BEFORE the Edelbrock Zinc Additive was added to it. Adding Edelbrock Zinc Additive SIGNIFICANTLY REDUCED this oil’s wear prevention capability. Just the opposite of what was promised. Buyer beware.

82. “Edelbrock Zinc Additive” added to Motorcraft 5W30, API SN, synthetic = 50,202 psi
zinc = 1680 ppm (up 573 ppm)
phos = 1275 ppm (up 517 ppm)
moly = 89 ppm (up 15 ppm)

The psi value here is 22% LOWER than this oil had BEFORE the Edelbrock Zinc Additive was added to it. Adding Edelbrock Zinc Additive SIGNIFICANTLY REDUCED this oil’s wear prevention capability. Just the opposite of what was promised. Buyer beware.

83. 30wt Lucas Break-In Oil conventional = 49,455 psi
zinc = 4483 ppm
phos = 3660 ppm
moly = 3 ppm

540 RAT
Member SAE (Society of Automotive Engineers)

 

Uh.... What was the question, again??

 

 

With this part. Appreciate the film strength testing and ZDDP additive testing as well. It is useful if taken as film strength testing.
In no way should this type of testing be considered a test for the effectivness of extreme pressure additives. ZDDP is the main extreme pressure additive and it's main purpose is to deposit a sacrificial coating of phosphorous on the parts that have enough load, heat and pressure to shear the film strength of the oil, This shears the ZDDP as well and deposits the phosphorous on the loaded part. This layer wears off and is redeposited continually. Once the film strength is broken the only protection on these highly loaded contact points is the sacrificial phosphorous coating. The pressure at the lobe lifter interface on a cam is enough to shear any oil no matter how good the film strength tests. At this point the film strength test is over and the extreme pressure additives start doing their job. Do not be fooled into assuming adequate ZDDP levels are nothing to concern yourself with, especially on high reving, highly loaded flat tappet applications. This testing does not test extreme pressure additives in any way. The UOA will still show Phos and zinc even after the ZDDP is broken down and worn off the parts. The residue is still in the oil but it can no longer do its job once it is coverted from ZDDP to zinc and phosphorous then worn off the part it was deposited on, at this point it is "used up" but still shows up in the analysis. This is why starting levels need to be over 1000-1200 so there are still adequate levels after 1-2-3000 miles.

 

Holy crap batman have you ever done a short post lol.

Next time can you start out with i'm a " member society of automotive engineers " and your second sentence " Your fine with your 10W-30W " LOL. Or if you go a little thicker to make the gauge look better to you your engine won't really blow up.

 

I'm just new here and am not out to contradicte anyone in saying that this is also what I'd come to understand after spending a tremendous amount of time studying the "bobistheoilguy" forum.

I'd suggest that anyone wanting to form their own conclusions to do so also.

That said, I very much appreciate the two in-depth oil studies that have been posted here and have learned even more from them about certain brands.

There is a great deal of oil knowledge in the forum BITOG - which consists of ; triboloigsts, engineers (SAE and others), chemists, speciality blenders, racers, experianced oil industry employees, and even more people that are very concerned about their oil.

..oh..and I love moly..

 

I am on there a lot as well and it is one of the best resources availabe for anything oil related. I love moly too. It was unable to be suspended long term until recently but it is a great extreme pressure additive (main ingredient in cam assembly lube) and one of the reasons ZDDP reduction has been able to be successful in modern oil.

 

Ok, So it looks like I will be changing the oil this weekend to 10-30 VR1 without mixing viscosities. The car will probably not see the road until mid or late March and I will keep an eye on the pressure gage. I will run the 10-30 until summer really hits then evaluate, but will probably run it all year unless I stare at the gage too much!

 

Can someone quote RATS post again please

 

:w illy::leaving :
howzat?

btw, I know you folks are right, but on a high mileage engine, I run whatever it takes to make me comfortable with what the oil pressure gauge reads ....and being old...er ,10lbs at idle aint it

 

Don't drive an old detroit two stroke diesel they idle around 5 lbs. Around 700 lb ft of torque at idle speed on 5 lbs of oil pressure. I'm guessing his L/82 might have two hundred lbs trorque at 3500 plus rpm with his 35/40 lbs of pressure.

Smokey that everyone likes to qoute 10 lbs for every 1000 rpm. He was a roundy round nascar man the 427s back then were kept at 7,000 to 7,600 rpm for several hours around 650 hp. This is why there brick cars saw 190+ mph. Surely this L/82 can survive on 35/40 lbs of pressure.

 

When new, the engine saw 10 psi at idle. Now that it has 'larger' clearances, MORE oil will flow through bearings/etc. with that same 10 psi. Not a problem.

If you want to run thicker oil so you feel 'warm and fuzzy' about it, OK. But, it just causes more wear on things at startup...before that thicker oil can actually get pumped through the bearings/etc. A 5W40 (or 50) weight oil will fix that risk; but those exotic weight oils lose that ability to change viscosity with time and use, so 3000 miles is probably when to change it out.

 

Maybe someday somebody will be able to explain to me why people obsess over their oil pressure and coolant temps so much, but I think it sort of explains why most OEMs install idiots lights instead.

 

If you can't 'see' a problem [or non-problem], you won't complain about it.

 

I drove 318 screemin detroits for years, use to say if there was no oil under them, you didnt have any in them,,but comparing them to a car engine is quite a jump

 

I had one my father had a couple in trucks biggest piece of junk ever put in a frame rail of a truck. Theres a V6/92 setting in a bus in the driveway. But any truck engine goes through a more brutal life then a car engine.

 

GM Detroit diesel engines convert perfectly good diesel fuel into useless noise!!

I can see a couple similarities between the sbc and the Detroit Diesel, bolts that go through into the cooling system or crankcase. If you put a detroit together using copper washers instead of the split lock washers, they don't leak nearly as much.

 

The new 4 stroke detroits have a good rep. in trucks. The old two strokes did not work well. They worked in other stuff that had good ways to keep them running cooler like massive radiators that can't be fit in trucks.