Rock chips on fender
 

When I put the car away last fall I noticed some small star shaped rock chips on the front fenders. I live on a mile and a half of gravel road and the tires are picking up rocks and causing the problem.. Does anybody use bed liner or ? under the fenders to stop this... would like to do something this spring.. Hate to move to town...Thanks

Re: Rock chips on fender
 

I used some brush on undercoating I got at the local chain auto chain store and it works well...It has been fine for 30 years now.

Re: Rock chips on fender
 

I have been looking at some of that. Rhino liner and others. Didn’t know if it would stay.

Re: Rock chips on fender
 

3M spray on undercoating.

Re: Rock chips on fender
 

If you have a compressor, I use 3m Body Shutz (per post 4) when applied with an undercoating nozzle. Some versions can be painted or left as applied.

Re: Rock chips on fender
 

You can buy undercoat spray in rattle cans.

Re: Rock chips on fender
 

For the undercoat in rattle can, or any undercoating or spray in bed liner for that matter, the original paint - in this case under the fender - needs to be squeaky clean then roughed up with at least 220 sandpaper. It needs the "tooth" to adhere and stay there.


Did the underside of my fenders with rattle can undercaoting as per the instructions from a pro undercoater/bed liner friend. Looks great but have not had car out on the road yet.

Re: Rock chips on fender
 

Do you have fiberglass fenders? They are notorious for star shaped cracks/chips. They are good for undercoating to adhere to as the bottom side is typically rough with fiberglass strands. Need a thick coat or multiple coats though.

Re: Rock chips on fender
 

My fenders are metal...there seems to be a lot of different products. just to pick one. I have access to a compressor so maybe that 3m stuff. ?