I'm thinking the answer is "Not much", since I don't recall the factory ones being that heavy in the first place. But I figured I'd ask anyway.

Before anyone asks, yes the OEM reinforcements behind the bumpers were removed years ago... and those DID weigh quite a bit.

When I made the switch on my old Challenger, the steel bumper and brackets weighed 33 lbs total. The fiberglass bumper I bought and fiberglass brackets I made weighed 3 lbs total. I laid up the glass bumper brackets off of the stock steel brackets. Came out great.

I have Unlimited fiberglass bumpers. Much lighter than the original steel. Front is mounted with fiberglass brackets. Heaviest part of my rear bumper is the OEM bumperettes that I use to mount it to the body with.

Stock bumpers are around 16lbs. A glass bumper about 4. The brackets are heavy as fudge

Many go to the trouble to make the bumper brackets LOOK like the stock brackets, only in fiberglass. Never really understood why that is. Who is going to look at the bumper mounts. Takes very little mount to attach a 4lb bumper

Don't do it Brad. You live in NoVa. I've seen how people drive there. My challenger got hit a couple years ago and let's say I would rather carry the weight than put glass bumpers or fenders on it.

They drive just as bad here in MD as they in Nor VA. LOL There're all morons.

Yep. Doesn't matter which side of the Potomac you're on around here, there are some seriously crappy drivers in this region.

Sounds like I need to look into alternative mounting approaches to get the most from switching to fiberglass bumpers. Thanks.

I don't disagree with this lol. Both states need to administer and IQ test before issuing a driver's license.