2014 GMC Sierra rear end thumping noise. Anyone had this?

southern_sierra · March 2, 2015

This morning started my truck up drove about a mile turned into a parking lot easied along about 5mph and all the sudden it sounded like something was wraped around the right rear enter wheel. It was a loud thumping sounds like everytime the wheel mad a revolution. My wife was with me and we both looked at eachother at the same time and she said whats that. So I know I'am not crazy because we both heard it. I got out looked underneath the truck and nothing was hung or wraped around anything wheels or drive shaft. I bounced on both corners of the bumper hard and easy no sounds there. It only made the sound then, once I started off again no sound and hasn't again. The 2014 GMC Sierra slt crew cab 4x4 Z71 with a 3.42 rear has alittle over 2500 miles on it. Anybody had this noise?

thewhitestallion · March 2, 2015

no telling what it was. if had had to take a shot in the dark I would say it was something in the rear end. maybe the g80 locking and releasing and locking again. was it slick outside? did you maybe spin the tires a little? maybe a defective ring n pinion. do you hear any whining coming from underneath the truck or from the back of the truck. a good speed to hear the whining is ~40mph.

also some people have had issues with the rancho shocks, could also be that but I don't know how loud those "thuds" were for the people that had that problem.

Jake56 · March 2, 2015

Did you have it in 4wheel drive ? Because doing that on pavement on a tight turning radius can make noises,

southern_sierra · March 2, 2015

Did you have it in 4wheel drive ? Because doing that on pavement on a tight turning radius can make noises,

Was not in 4wheel drive or auto 4w, was dry and 50 and was going in straight line on smooth pavement when it started.

no telling what it was. if had had to take a shot in the dark I would say it was something in the rear end. maybe the g80 locking and releasing and locking again. was it slick outside? did you maybe spin the tires a little? maybe a defective ring n pinion. do you hear any whining coming from underneath the truck or from the back of the truck. a good speed to hear the whining is ~40mph.

also some people have had issues with the rancho shocks, could also be that but I don't know how loud those "thuds" were for the people that had that problem.

I'am thinking it was comming from the rear differential. I do get the clunking sound from time to time from foward to reverse and reverse to foward and sometimes getting off the gas and back on at lower speeds. But this sound was a steady thump like something was hitting ever time the wheels made a revolution. I can't get the shocks to make any noise. I carry about 250 lbs all the time in toolboxes so the shocks are loaded alittle. I was going maybe 5mph when this sound started and stayed at that speed before stopping after about 75 yrds after that hasn't done it again. This was the first drive of the day so every thing was at cold temps. Had driven about amile after this started at about 35mph before making a right turn into a parking lot with smooth pavment. My not ever do it again we will see.

southern_sierra · March 4, 2015

no telling what it was. if had had to take a shot in the dark I would say it was something in the rear end. maybe the g80 locking and releasing and locking again. was it slick outside? did you maybe spin the tires a little? maybe a defective ring n pinion. do you hear any whining coming from underneath the truck or from the back of the truck. a good speed to hear the whining is ~40mph.

also some people have had issues with the rancho shocks, could also be that but I don't know how loud those "thuds" were for the people that had that problem.

The more I think about it I think it was the locking rear too. This is the first gm truck I have had since 1995. Told my brother about it the first thing he ask me, did it have automatic locking rear.

Coach Hill · March 4, 2015

If it makes you feel any better, my truck did that once about 10 months ago on a trip. My wife and I spent the night in a hotel. The following morning, I remote started the truck (had lots of frost on it), we loaded up, left the hotel and pulled into a McDonalds for breakfast. When I slowed down to turn into the parking lot it made the same noise you are describing. I was worried to death so I pulled across the street to a Chevy dealer that was nice enough to take a look at it. They couldn't find anything and it hasn't done it since that time. Not even once more.

southern_sierra · March 5, 2015

If it makes you feel any better, my truck did that once about 10 months ago on a trip. My wife and I spent the night in a hotel. The following morning, I remote started the truck (had lots of frost on it), we loaded up, left the hotel and pulled into a McDonalds for breakfast. When I slowed down to turn into the parking lot it made the same noise you are describing. I was worried to death so I pulled across the street to a Chevy dealer that was nice enough to take a look at it. They couldn't find anything and it hasn't done it since that time. Not even once more.

Thats funny thats what we did left the hotel pulled in th cracker barrel to eat breakfast. Thanks for the info makes me feel better about it.

phattiron · March 7, 2015

Please know, that I'm with my 17th GM truck with positraction rear differential. Having said that, every posi rear end makes noise, the newer the louder, the fastest way to break these axles in , is to romp them, (not light foot them), they must break-in. I never had a GM rear axle with posi go out. Check the fluid level, if its per GM, break the axle in, this takes 5000 to 8000 miles to lower the noise levels with average to hard driving, which is what they are designed to do. If you use your truck like a car, it may take up to 15000 miles to break them in, drive the crap out of it (heavy accelerating around corners) to silence some of the noise.

All posi rear ends make noise, if you don't like the noise, get a car???

Posi Dude.

enroberts · April 6, 2015

My truck makes this noise too. Sounds like the spare tire is loose or the bed is knocking around. I tried to spray the leaf springs but it made no difference. It only happens at slow speeds while turning (often on a slight incline). It does it every time I pull in my inclined driveway. Headed to the dealer this week. This is far from a rear different sound. I know what position noises are (I've restored Corvettes and own a 2010 Camaro and have had countless other GM position vehicles) and this noise is not from the diff.

enroberts · April 7, 2015

I did a lot of reading on this today in several areas of this and other forums. All kinds of resolutions were attempted and at least 30 people claimed the issue was coming from 30 different places. So I decided to get under the truck tonight And really find where it was coming from. First, the noise is only present when turning either left or right slowly and often times more prevalent when going up slight incline while turning (as I do when entering my driveway or some parking lots). It can also be heard when slowly going over bumps or articulating the rear axle From left to right. If I jump on the bumper at any time of the day, in any weather, at any warm or cold point for the truck the noise is not there. HOWEVER what I found tonight was that if I shake the truck left to right by holding the bedside and shifting weight left to right the noise is VERY obvious! Here is a link to a video I took in a parking lot tonight:

2014 GMC Sierra rear end noise:

After I took this video I went home and had my son hold the camera while I shook the truck again. I was quickly able to pinpoint the noise to the rear leaf springs rubbing each other. Here are two videos of the rubbing location at the rear or the left and right springs. The same can be said for the front of both springs too.

2014 GMC Sierra rear end noise (spring):

2014 GMC Sierra rear end noise 2 (springs):

Anyway, I have an appointment for 10am tomorrow with the dealer. I'm sure the truck will spend at least one day there but I will take the service person out for a drive to show them the noise and feeling inside the truck then also duplicate my test from tonight with them. My steering wheel also needs to be replaced and my windshield is having an issue too. I really love this truck and these are all issues that can be solved. Hopefully this video helps others with the same issue in the rear.

southern_sierra · April 7, 2015

Please know, that I'm with my 17th GM truck with positraction rear differential. Having said that, every posi rear end makes noise, the newer the louder, the fastest way to break these axles in , is to romp them, (not light foot them), they must break-in. I never had a GM rear axle with posi go out. Check the fluid level, if its per GM, break the axle in, this takes 5000 to 8000 miles to lower the noise levels with average to hard driving, which is what they are designed to do. If you use your truck like a car, it may take up to 15000 miles to break them in, drive the crap out of it (heavy accelerating around corners) to silence some of the noise.

All posi rear ends make noise, if you don't like the noise, get a car???

Posi Dude.

I have been driving trucks for over 35 yrs never had one to make rear end noises like this one. This is only the 2nd gm I have had last one was 1995 all have been fords and toyota. Had one ford 1978 with locking front and rears. Iam not a car person I farm for a living.These trucks have a lot of little problems. As for the rear end noises the one I discribed in the opening post has only happen once but have had others that when coming to a stop sounds like a rock rolling from the back of the bed to the front and has done this several times. Could be something inside the frame just can't never tell. Other than that like the truck alot.

enroberts · April 7, 2015

southern_sierra did you watch my videos? It's not rocks, it's the springs.

sugarjohnson · April 7, 2015

Resolution?

southern_sierra · April 8, 2015

southern_sierra did you watch my videos? It's not rocks, it's the springs.

My truck makes no noise at all when shaking it from side to side easy or as hard as you can and makes no noise when bouncing each corner up and down . The noise in the original post I made has only happen once and I think it was the rear locking differential. The sound of something rolling from back to front of bed or in frame when coming to a stop has happen 3 or 4 times.