How to Check the Differential Fluid in a Dodge RAM 1500
- 1). Locate the fill plug on the rear and front differentials. The plugs are round, slightly convex rubber pieces near the top quarter of the differentials.
- 2). Slide a flat-head screwdriver under the lip, and pop out the plug.
- 3). Insert the short end of an L-shaped Allen wrench into the hole, and slightly spin the Allen wrench. Remove the Allen wrench. The differential is full if there is a slight amount of fluid on the tip of the Allen wrench. Fill, as necessary, using the appropriate weight oil.
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