reble47,
Search the 5 ton forum as there many threads on it.
Bottom line, What is in it right now? Yellowish oil is 10w or 15w40 plain ole motor oil. Red oil is dexron III Atf. I would top off with whatever is in there and plan on changing both the pan filter and spin on filter by the heater core and refill with dexron. Should give you better shifting that is less harsh. Allison recommends their proprietary oil which is pricey. Allison manual that I read suggests changing filters flush out what you can , refill, drive several hours, and flush again, refill and good to go. 5-10 gallon investment.