So Ive been to every parts house in town, and nobody has Dexron III
I have found Dexron III on the internet, but hesitate to buy some 10 year old Tranny Fluid off of some warehouse shelf somewhere.

I found this as WalMart



This Castrol brand states it is for GM models produced before 2005

But as I am using it for Power Steering Fluid as well, I am looking for a second opinion.

 

Well, the label on the back should tell you the specs. I am assuming it is a Dexron III. Castrol is a great brand, been using it for years. How much is it a quart?

 

You are fine. They cannot list every car that it will work in on the bottle, not enough space.
I used Valvoline High Mileage but like you said, that is all you could find.
I used that same stuff in my wifes Volvo's tranny and power steering.
That calls for Dexron in the trans and Mercon in the power steering.

 

Vavoline has the same wording on their MaxLife stating it covers the Dextron 3 requirements so go for it. By the way, I have been running the Vavoline ATF for the last year with no issues.