The Ohio & her sisterships were never oilers, only tankers. The were also a wholly separate, custom design, built for the TEXACO Oil Company, NOT part of the Maritime Commission program. So "Type T whatever" does not apply. They were also larger than a T-2 type ship.
As far as I know Ohio was painted in overall medium grey.
USS Chicopee was one of 2 T-2 size tankers built for the ESSO Company and taken over by the Navy.
Please note "T-2" does not indicate a specific design, only a size of between 490 & 500 feet long. (Don't quote me on these numbers, but they're close) There were at least 6 different classes of T-2 tankers. All similar in looks, but of different lengths and design.
Thanks for indulging me in a ramble on a subject of much interest to me.