Should i use primer when painting a gray bumper trim?

Hello i recently bough "rust-oleum trim and bumper paint" to paint the trim on my bumper. The trik on my bumper is like a dull gray color. Should I use black primer on it or should i just spray the pain on? I heard it peels without the primer and i want a dee black look to match my truck. (2005 ford ranger xlt)

Kenny2016-05-23T11:33:51Z

See what the spray can say. Usually it's recommended. Find a primer for plastic also; like your trim and bumper paint.

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