1. Engine Block Drain Plug: This is located at the lowest point of the engine block. It's usually a bolt or a plug, and you'll likely need a wrench to remove it. The exact location can vary slightly depending on the specific engine (2.3L, 2.9L, or 4.0L), but it's always on the bottom of the engine somewhere near the oil pan. You might need to get under the truck to access it easily.
2. Radiator Drain Cock: This is located at the bottom of the radiator, usually a petcock (a small valve) that you can turn to open. This will drain the coolant from the radiator itself.
Before you start:
* Let the engine cool completely. Hot coolant is under pressure and can scald you severely.
* Place a drain pan underneath to catch the coolant. Engine coolant is toxic and needs to be disposed of properly.
* Have appropriate tools ready, including a wrench (size will depend on the drain plug) and a drain pan large enough to hold several gallons of coolant.
Finding the exact location of these plugs might require a bit of searching under your truck. A repair manual specific to your 1990 Ford Ranger's engine will be the most helpful resource for precise locations and diagrams. You can often find these online through automotive parts websites or online libraries.
