- 1). Consult your Sentra manual for the size of your trunk floor. Your replacement mat needs to be the same size.
- 2). If the the manual is not available, use a tape measure to determine the dimensions of your Sentra trunk. The shape of a Sentra trunk generally is not a uniform rectangle, and you will need to measure length and width.
- 3). Purchase an appropriately sized new trunk mat from the factory or from an auto parts dealer. The trunk mat can be cut to fit if it's too big.
- 4). Remove the old trunk mat from your Sentra and discard if no one wants it. Few places accept donations of used auto accessories, but check with the local Goodwill.
- 5). Cut the trunk mat with sharp scissors or a utility knife to fit your trunk if it is too big. Cut the mat to the measurements of the trunk or lay the old mat down on top of the new mat and use as a template.
- 6). Place the new mat in the trunk of your Sentra and smooth it out. Cut edges with sharp scissors or a utility knife if the trunk mat needs further alterations.
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