Clunk on Deceleraton

brandonbvr · July 28, 2014

Has anyone been experiencing a very loud clunk noise on decel? I have read in other posts it is the trans or torque converter learning how you drive. It just doesn't seem normal.

scott19677 · July 28, 2014

Yeah. Ive bought two different 14s . Both have done that. Sometimes so bad it will scare the crap out you. Seems to be a combo of the stock trans tune(horrible), V4 switching in and out, possibly the way these direct injection engines cut fuel and just feel different on deceleration. Try driving in M5 mode and ,or tow/haul mode if you have it. Feels and drives a lot better. Like a different truck. This keeps the engine out of V4. Trans will get better after some miles on it. I think there is a bulletin out explaining about the drivelash or backlash in the rear end across a lot of cars and trucks. Or as the service dept will tell you " OPERATING AS DESIGNED".

brandonbvr · July 30, 2014

I observed coming home from work this morning in cooler temps my truck rode like a cadillac at all speeds that were previously giving me shaking and vibrations (70-80mph). My tires are Michelins set to 32 psi cold (recommended on door tag). It was 60 degrees F this morning on my 30 mile all highway commute home. My trans temp was 170 degrees F. I also didn't experience any harsh downshifts or clunks on decel.

Something tells me that something in the driveline is out of spec or warps when it is hotter because when it is 80 degrees outside my truck doesn't ride this nice on the highway that's for sure.

Has anyone been able to notice these same results? Any ideas or input? My truck goes back to the dealer on Monday of next week.

GMC-AT · July 30, 2014

mine does it sometimes... seems worse when cold.

Tattooo · August 1, 2014

Mine did it alot when I first got it....now I have 3000 miles on it and it very rarely happens

BIGDOGx · August 1, 2014

Isn't this the old slip yoke issue that plagues many gm trucks? I know my 05 silvy does it from time to time and also had it on my 95 zr2.

Crooks · August 19, 2014

I am getting a clunk on deceleration at low speeds under 20mph sometimes. Anyone get this fixed?

pm26 · August 20, 2014

Yeah. Ive bought two different 14s . Both have done that. Sometimes so bad it will scare the crap out you. Seems to be a combo of the stock trans tune(horrible), V4 switching in and out, possibly the way these direct injection engines cut fuel and just feel different on deceleration. Try driving in M5 mode and ,or tow/haul mode if you have it. Feels and drives a lot better. Like a different truck. This keeps the engine out of V4. Trans will get better after some miles on it. I think there is a bulletin out explaining about the drivelash or backlash in the rear end across a lot of cars and trucks. Or as the service dept will tell you " OPERATING AS DESIGNED".

Are they admitting that it is a clunker?

"So you thought you can get a clunker for $ 1000 or less? Here at GM we sell them for $ 45,000!"

fondupot · August 20, 2014

Mine did it stock and does it with my Blackbear tune. Gotten used to it.

GMC-AT · August 20, 2014

I get it on my truck... mostly under 25mph.

fondupot · August 20, 2014

I get it on my truck... mostly under 25mph.

yea its usually around 25-30 mph

sirbOOm · August 20, 2014

I get this and a clunk from time to time if I catch it in-between a gear or at a mysterious time otherwise when pressing the gas after coasting or decelerating without brakes. I got this on my 2011 Silverado with the same transmission (and I'm assuming same transfer case). It's characteristic of the design - slop in the drive train, apparently. You'd think they would have engineered it out because I have yet to sit in a Ford, Nissan, Toyota, or Dodge truck that does the same thing. It's really concerning. I've taken it to the dealer twice. Can't replicate it EVER because it doesn't happen until you've been driving for a while and, of course, they aren't going to spend that much time on it.

pm26 · August 20, 2014

It seems to vary from truck to truck, even for previous generaiton. For exmaple, my neighbor got rid of his 2005 Sierra Z71 with only 30k miles because he could not stand the driveline clunk. My 2006 Z71 crew cab has almost no clunk issues. Very rarely I get a faint clunk when making a slow 90 degree turn and it happens to downshift and I step on the gas at the same time.

fondupot · August 21, 2014

I get this and a clunk from time to time if I catch it in-between a gear or at a mysterious time otherwise when pressing the gas after coasting or decelerating without brakes. I got this on my 2011 Silverado with the same transmission (and I'm assuming same transfer case). It's characteristic of the design - slop in the drive train, apparently. You'd think they would have engineered it out because I have yet to sit in a Ford, Nissan, Toyota, or Dodge truck that does the same thing. It's really concerning. I've taken it to the dealer twice. Can't replicate it EVER because it doesn't happen until you've been driving for a while and, of course, they aren't going to spend that much time on it.

Yea seems to be a common characteristic of leaf sprung trucks. My 2002 Silverado did it, my dads had a couple 2007 silverado work trucks that did it, My 2011 F150 did it, my 2014 Sierra does it.

However, I did drive a rental 2012 or 2013 Ram for about 4 days with coil spring read end and never experienced it.

GMC-AT · August 21, 2014

Does the issue also seem more pronounced when the truck is cold? It does for me... seems like after the truck is warm it doesn't bang and clunk as much..