Here's why:
* Fluid type varies: Power steering fluid type depends on the specific model and year of your GMC. It could be mineral-based, synthetic, or even ATF (automatic transmission fluid).
* Consult your owner's manual: The most reliable source for information is your vehicle's owner's manual. It will specify the exact type of power steering fluid needed.
* Check with a dealer or mechanic: If you don't have the owner's manual, your local GMC dealer or a trusted mechanic can provide you with the correct fluid specifications for your 1988 GMC 350.
Important Note: Using the wrong type of power steering fluid can damage your steering system. Always double-check the recommended fluid before adding it to your vehicle.