"New" (8-02) PAG Oil

[rek]

Never a dull moment.... In checking over my replacement Delco Drier, I noticed three "Stickers" to choose from, to be placed on top the new Accum/Drier. They all specify Synthetic Oil #12345923.

It's for my 96 Eldorado. I ordered parts by my VIN, at the dealer. The dealer came up with

#12378526 oil.

Well, 923 is ISO 150, and 526 is ISO 46.

"When servicing a compressor, technicians must follow manufacturers' recommendations relating to both oil quantity and type. Recently (August 2002), General Motors Corp. released a new PAG oil that went into production in certain 2002 model vehicles. This new GM Universal PAG Oil, U.S. Part No. 12378526, is compatible with all GM R-134a A/C systems (refer to GM Bulletin No. 02-01-39-004). Also, in December 2002, GM issued a new compressor oil balance procedure, used when replacing a compressor, which supersedes all previous information in their service manuals (Refer to GM Bulletin No. 02-01-38-006). "

"New PAG oil. Just as the air conditioning season comes upon us we get word from General Motors that a new universal PAG oil (Part No. 12378526) is now available for all 2006 and prior R-134a systems, excluding vehicles equipped with R4 and A6 compressors. According to GM, the new oil is formulated with a very specific additive package that provides better, more lasting lubricity to the compressor. The oil is supplied in 8-oz. cartridges in packages of six, and can be installed using injector J-45037."

"New compressor oil. For your information, GM began phasing in a new universal PAG oil a few years ago. The new oil, which goes by Part No. 12378526, made its debut in 2002 in Chevy Cavaliers, Olds Aleros and Pontiac Grand Ams and Sunfires, all with the 2.2L Four (VIN F). By 2003, it was in every single GM car and truck sold, including the HUMMER H2.

"GM says the new lube is fully compatible with all prior oils used in all of its R-134a refrigerant systems. It comes in convenient 8-oz. cartridges, in packs of six. If your jobber stocks ACDelco aftermarket parts, you can order the identical oil under Part No. 88901445/10-5026 (eight 8-oz. cartridges)."

I'll try to find the GM Bulletin No. 02-01-39-004.

[rek]

**** Delphi /Harrison Compressors****

Use ISO 150 PAG for Delphi/Harrison H-6 Compressors!

"The "universal oil" approach is taken by General Motors, which has been using compressors made by ***Delphi Harrison***, Denso, Sanden, Mitsubishi, Zexel and Visteon. GM approved the 46-CSt oil from Idemitsu, the oil supplier to Visteon and reportedly most Japanese compressor manufacturers. The 46 is being used for factory installation on all but*** Delphi compressors***, and GM will be marketing this oil to its dealers. It's the service oil for all GM R-134a systems, except those retrofitted from R-12.

GM's okay for 46-CSt oil basically sets a de facto standard for almost all compressors, within some limits. Some rotary vane compressors (such as the Denso TV in some Toyotas) call for a specific oil.

And then there's Delphi Harrison. The new Delphi CVC-6, CVC-7 (compact variable compressor, sixand seven-cylinder, introduced in 2001) are factory-filled with oil from a U.S. supplier (Union Carbide), and shipped to both GM and the aftermarket. This oil has a viscosity of 55 to 65 CSt, but that's close enough to the 46-CSt oil used in other GM compressors, and Delphi has no objection to substitution with the 46CSt oil. That's important, because GM's first approval of the 46-CSt oil for service started in 2002 and applied to 2002 Chevy Cavalier, Pontiac Grand Am, Olds Alero and Pontiac Sunfire cars with the 2.2L four-cylinder engine, and that engine has a CVC-6 or CVC-7.

The older-design Delphi Harrison compressors (***H-6*** axial six-cylinder, V-5 and V-7 variable displacement compressors, and R-4, still manufactured for service) also are used by GM. For these Delphi specifies the 125- to 135-CSt oil, but allows a topping up with the 46-CSt.*** However, if a GM system requires at least 50% or more of a fresh fill-Le., 4 ounces or more-then the** heavier oil** should be used, Delphi cautions.***

In the real world, we suspect the oil situation will come down to this: 46 CSt will be going into all brand-new compressors ***except the older-design Delphis (H-6, V-5N-7 and R-4)***. Remanufactured versions also will get the 125- to 135-CSt oil, and so will top-ups on older compressors (of all makes) that are somewhat noisy. Other remans will be lubed with a factory fill chosen by the remanufacturer, and if shipped dry, will get whatever is on the shop's shelf. The 100- and 150CSt oils are likely to fade."

[KHE]

The imports and Chrysler products use the low viscosity oil. GM uses some Denso compressors on the Chevy trucks I believe, so that may be the reason for the standardization on the lower viscosity oil.

Despite the bulletin that says low vis. oil is all the sudden OK despite numerous labels that state "Use recommended oil or system may be damaged", I would not use the low viscosity oil in a vehicle that calls for high viscosity (150) oil.

This is getting as bad as antifreeze....

[rek]

"This is getting as bad as antifreeze.... " AMEN.... Along with the viscosity Alchemy there's

DEC (Double End Capped) VS Single End Capped PAG.........

[KHE]

I think the double end capped PAG oils are less susceptible to absorbing moisture.