2016 clunking?

Jcoot24 · September 11, 2016

My 2016 has just over 7k miles on it and I've noticed a clunking when starting and stopping. I brought it to the dealer and they claimed it was normal. They said each component has some give and when you add them up there can be a centimeter plus of give that shifts. I'm no mechanic but that sounds crazy on a 45k plus truck to allow it to do that. Anyone have this issue?

Toxicgoober · September 11, 2016

Might be driveshaft. I know the last gen Tundras had a clunk and thump sensation at start/stop that originated in the driveshaft linkage. Wasn't a mechanical issue from what I understand, just obnoxious.

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Jcoot24 · September 11, 2016

Yea it's pretty brutal. I've had a few people comment on the noise.

SouthernSilveradoGuy85 · September 11, 2016

A lot, including me, has had this clunking with the K2 trucks. It's from the u-bolt nuts being too loose. I believe the TQ spec is 79 ft/lbs and when I did it they turned over 1 full turn. After doing that the clunking stopped completely. So if you or someone you know has a TQ wrench then try that.

Jcoot24 · September 11, 2016

Thanks SS

I'm going to try and find someone that can try that for me.

FL335i · September 11, 2016

Original Poster- as stated above, it's the loose U-bolts. I torqued mine and was shocked how loose they were. Search the forum, I started a post on this. It's 79 # + 135 degrees or something like that. My clunking all but stopped since I torqued the U-bolts. I'm surprised GM is not tightening these at the factory more.... talk about a risk.

SkiDooNick700 · September 11, 2016

I had the dealer tighten the ubolts during an oil change. It doesn't do it anymore

WytRyd50 · September 17, 2016

Can anyone take a picture of the ubolt that needs tightened? Thank you!

SouthernSilveradoGuy85 · September 17, 2016

Can anyone take a picture of the ubolt that needs tightened? Thank you!

It's the u-bolts that hold the rear axle to the leaf springs. The nuts are on the bottom just on the underside of the axle. 2 u-bolts and 4 nuts on each side. They will be between the back of the brake rotor and the shock.

WytRyd50 · September 17, 2016

It's the u-bolts that hold the rear axle to the leaf springs. The nuts are on the bottom just on the underside of the axle. 2 u-bolts and 4 nuts on each side. They will be between the back of the brake rotor and the shock.

Thank you sir! I thought they were near the driveshaft based on previous comments. I appreciate the clarification.

amxguy1970 · September 17, 2016

Some occasional clunk isn't abnormal, mine will on occasion depending on the downshift/speed. Since you only spent 45k on your truck they can clunk, if you had spent 50k or more they don't clunk. You should see how bad the WT owners trucks clunk...

Tyler

f8l vnm · September 17, 2016

Pics would be great guys. Thanks

benjdow · September 17, 2016

So grateful I came across this thread! Mine is doing the same thing, was thinking I was in for a crazy repair cost. Torqued them down, all is well. Thanks guys!

Dnt · September 17, 2016

On my old 2014 the U Bolt torgue did help but the truck still had the clunk. I cured it 100% with a set of leaf spring clamps installed 5" forward of the rear axle block. about 20 bucks at your local auto parts for a set of 2 (1 for each side) My new 2016 Denali has No clunk so far. Iit has some kind of crazy magnetic ride control or something on it so maybe that keeps it from clunking i don't know... I know there were some pics on some old threads of the U Bolts and leaf spring clamps you might have to do a thorough search to find them. Some people claimed that the leaf spring clamps and U bolt torque helped there shake and vibration so it might be part of that massive 700 page shake and vibration thread LOL

seamus2154 · September 17, 2016

Some occasional clunk isn't abnormal, mine will on occasion depending on the downshift/speed. Since you only spent 45k on your truck they can clunk, if you had spent 50k or more they don't clunk. You should see how bad the WT owners trucks clunk...

Tyler

Well I can see the sarcasm, my truck stickers for 74K and it clunks quite bit. Mine is a Denali Yukon XL so this u bolt theory won't apply as it doesn't have leaf springs. Both of my pickups in this platform did the same thing. Its the very poor programming of the transmission IMHO. It never knows what it's doing when going slow. 2 6 speeds and now the 8 speed.