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2017 GMC 1500 - Clangs - It can't be the lift kit, right?

When going over a bump, any size bump, I hear a clanging sound from the back end of the truck, it almost sounds like the spare tire is loose or the back bumper is loose, but not… I do have a ~ 3 inch lift kit that came already installed, the truck rides great!! 23.000 miles.

Have all the bolts been checked? seems to be the common cause on various lifted trucks. Something’s loose or hitting at any rate.
A co worker had the shop that did the lift on her Jeep Wrangler had the shop give her the “they all do that” when she asked them to investigate noises that weren’t there before the lift. I wanted her to try another location to see if she got better service but ended up trading it in as is (She seemed to trade up every 6mo or so)

This is one of those issues best solved by boots on the ground…not butts in a chair. The list of suspects can be rather long in light of all the suspension mods. But not everything can actually clang…most solid things clunk and hollow items clang and yes this is my personal scientific nomenclature on that subject, lol.

Shouldn’t be too difficult to figure out however… Each component that is able to “clang” will do so with a unique quality. So for starters I would lie under the vehicle with a suitable tool…and see if you can find the culprit by tapping around. I’ve solved more than a few of these types of issues this way. After a while you dont need to tap around because you have the soundtrack to certain items recorded in your head, but in your instance, this is what I would recommend.

If your sound description is accurate my first instinct would be to say it will be an exhaust component…either hitting directly on something…or one of the exhaust hanger studs hitting something or even a heat shield, but those tend to just rattle.

Exhaust pipe is very famous for a “Clang” type of sound …

Man, this brought back some memories. Bought a 3/4 ton Silverado once that did the same thing and drove me nuts trying to find it. I had friends driving it over 2x4 and 4x4 while lying down next to it and watching the rear end. Talk about trust :grinning: anyway finally figured it out. It was a farm truck in previous life and they installed suspension limiters for the rear end. They were close enough that a sharp drop would cause them to contact briefly and make a loud clunk sound.

Did you install longer rear shocks when the lift kit was installed? If you did not, you may be hearing the shock topping out and smacking its internal parts. You won’t hear this very long as the shock will break pretty shortly.

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I really think it could be related to the shocks not being the correct size, these are the factory shocks, how could I find the correct size shock for this truck with the ~ 3 inch lift kit…

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You may be correct… But only if the shocks are involved in the lift process. Most lift kits only move the body up off the frame… however with unit body constructs… there may be a kit needed to help the shocks deal with the extra height… or longer shocks all together. I’d have to look up the geometry of your particular truck and or look at the parts in the lift kit.

You can look all this crap up on the internet…

Contact the people who installed your lift kit… or the manufacturer of the lift kit in your truck and ask them what rear shocks they recommend with their 3 inch lift kit.

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Since the noise is apparently easy to duplicate . . .

Have the shop use their chassis ears . . . that’s a trademarked product AND one that Click and Click regularly recommended, by the way . . . to figure out what’s causing the noise

If the shop doesn’t even know what those are, they may not be the one to figure this out.

The tools aren’t even that expensive

So in my opinion, there’s no excuse why the shop shouldn’t have one as a shop tool

I use them regularly, and they really do make chasing down noises MUCH easier

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Some clanging can be caused by a cracked rotor shield. Other sheet metal can also do it.