Welcome to the forum. Even though there should be some kind of sticker under the hood or nearby the engine to give a couple specs, sparkplug gap, etc., it usually lists oil type. If not, there really isn't a specific you need under normal weather conditions, where it is above freezing and under 95ish, and that is a standard 10-30 or 10-40, both good for heavy vehicle driving around and won't thin out under the stress of travelling. You could also go with a synthetic if you intend to travel a lot, helps keep from changing the oil so often, that would be a 5-30 weight and can be good for a little improvement of gas mileage. The transmission is a little easier. ATF-4. It is a synthetic and used on everything after the early 90s, anything else will mess the transmission selonoids up.