Generally, for a 1999 Ranger, a conventional oil with a viscosity of 5W-30 or 10W-30 would be a good choice for most situations. If you live in a very cold climate, 5W-30 might be better. If you live in a very hot climate, 10W-30 might be preferable.
Here's what you should do:
1. Find your owner's manual: This is the most reliable source of information. It will specify the exact oil type and viscosity recommended by Ford.
2. Check the oil fill cap: Sometimes, the recommended oil type is printed on the oil fill cap.
3. Look for a sticker under the hood: There may be a sticker under the hood providing maintenance information, including recommended oil.
4. Consider using a higher quality oil: While conventional oil is fine, synthetic blend or full synthetic oils offer better protection and longer life, especially in harsher conditions or if your Ranger has higher mileage.
Important Considerations:
* API Certification: Look for an oil that meets or exceeds the API certification listed in your owner's manual. Older Rangers usually required oils meeting older API standards (like SG, SH, SJ, etc.), but modern oils usually exceed these.
* Mileage: Higher mileage engines may benefit from higher viscosity oil or an oil with additives designed for older engines.
* Driving Style: If you do a lot of stop-and-go driving or tow heavy loads, a higher quality oil might be beneficial.
Don't just rely on this information. Always refer to your owner's manual for the most accurate and up-to-date recommendations for your specific 1999 Ford Ranger.
