which Oil I can use?

Hi,

I don't want begin an discussion which Oil can I use for an 98's 3.8L Lumina?

The Price are 5W30: 12,99 and 5W40: 22,90 the number after the W tells me something about the oil if the engine is hot, but what is better 40 or 30? Or safer for my engine.

From GM 98 Lumina service info:
• For the 3800 L36 (VIN K) engine, SAE 10W-30 is the recommended viscosity. However, 5W-30 may be used if the outside air temperature is lower than 16°C (60°F). Do not use other viscosity oils, such as SAE 20W-50.

GM said too we should just use Dex Cool... And the result was broken LIM gasket.

Hi,

I don't want begin an discussion which Oil can I use for an 98's 3.8L Lumina?

The Price are 5W30: 12,99 and 5W40: 22,90 the number after the W tells me something about the oil if the engine is hot, but what is better 40 or 30? Or safer for my engine.

my 1998 lumina 3.1 had 45,000 on it when i bought it and has 155,000 on it now. i have used 10w30 for 9 years. no problem in the Louisiana climate.

Irrelevant to the "maybe" Dexcool issue, 10/30 as stated.

Motorcraft or Valvoline 10w30 semi-syn all it's life, 162,000 now, runs like new.

GM said too we should just use Dex Cool... And the result was broken LIM gasket.
The gaskets broke because they were defective, not from DexCool.

The gaskets broke because they were defective, not from DexCool.

Thank you. My thoughts excactly.