Oil for transfer case API sa vs sb

[joegreen]

So my transfer case requires sae 30 non detergent oil. I have been using sae 30nd sb rated oil. Most of the cheap non detergent oils I find are sa rated. I couldnt find what the difference in sa vs sb really was. I would like to use supertech sae 30nd but it's sa rated. I just am not sure if sa rating is not robust enough for a chain drive transfer case.

 

[jakewells]

Not really going to matter if you use either but using SA is not going to hurt anything they are practically the same.

 

[Jimzz]

SA means no testing is required, its basic pure petroleum oil with nothing else in it.

SB means it has some basic corrosion inhibitors and other light additives.

I would at least try to get the SB if you can.

 

[zrxkawboy]

NAPA 30 nd is SB.

 

[MolaKule]

SA oils have some Anti-Foam but no Anti-Wear additives.

I would use a later API oil that has some Anti-Wear additives.

 

[joegreen]

So my transfer case is a new process 203. Some manuals call for 10w40 but it was specced for 30nd. I was using napas 30nd because it was sb I just didn't want to spend for sb if cheaper sa was fine. There was mention about 10w40 foaming up from the chain whipping around and that 30nd did not have this issue. This is an AWD transfer case where the chain is always spinning even in 2 wheel drive.

 

[joegreen]

Any thoughts on 10w30 vs 30nd for chain and gear lubrication and foaming?

 

[MolaKule]

Love the K20 as that was when PU trucks looked like trucks.

As far as the TC lube, I would go with a 10W40 mineral oil since the mineral oil usually thins to 30 grade when hot.

 

[NH73]

Don't today oils have anti foam agents in it? Wouldn't modern 10w40 work?