Shake or Vibration Issues

[abominable z71]

 

 

 

 

 

 

 

 

Im really thinking of just going for it and having a shop change my axles. Has anyone done this yet?

This has been brought up in the past and only a few people have opted to spend the money to put in a set of Yukon axles or machine the factory axles and the results have been mixed. Not nearly enough data to say whether or not it helps. As far as vibrations are concerned they consist of 3 components the actual mass of the imbalance the distance of the mass from the rotational axis and the angular frequency or RPM at which the assembly turns. So in this case a 1/4 ounce located on the hub 3 inches from the center has little influence compared to say a quarter of an ounce 15 inches from the center like the edge of the tire.

 

in the video you can see that the edge of axle hub has not been machined and the still is still in its raw state from when it was forged. This makes the axle cheaper to manufacture because it is one less op while the axle is in the machining center getting turned, faced and drilled. The real question is whether or not the majority of trucks produced that don't vibrate have this condition, just because trucks that vibrate have it doesn't mean that trucks that don't vibrate don't have it, which makes investing 3 or 6 hundred dollars depending on whether one or both axles have the issue hard to do. If you have a shop swap out both rears I'm guessing you're looking at somewhere between 800 to 1200 dollars for parts and labor. If you go this route hopefully its worth the investment.

[abominable z71]

 

 

UPDATE... Drove about 100 miles today on the highway with the shaft aligned and balance and it is different. There is still a vibration but not as bad as it was. I'd say 50% is gone. While I was under the truck re-installing the driveshaft I noticed that the yoke at the output shaft on the transmission seems to have some play in it. Enough to make it move noticeably. Hard to say that is the cause though. If you get under your truck just push up on this yoke at the trans and see if yours does it.

Being that you're down in riverside you have an option not a lot of people have. There is a tire shop in signal hill that trues and balances tires while on the truck. This would take into account any imbalance from from the hubs and rotors that traditional tire balancing can't account for. Nate Jones tire in signal hill is one of the few shops left these days that can still perform this kind of work. It's a lot more common on trucks running large tires like 37's and bigger but it's something to keep in mind and might be worth a shot.

[Silver16]

Being that you're down in riverside you have an option not a lot of people have. There is a tire shop in signal hill that trues and balances tires while on the truck. This would take into account any imbalance from from the hubs and rotors that traditional tire balancing can't account for. Nate Jones tire in signal hill is one of the few shops left these days that can still perform this kind of work. It's a lot more common on trucks running large tires like 37's and bigger but it's something to keep in mind and might be worth a shot.

There are a few but yes those dudes are good. Another one in Santa Ana too...can't remember the name been years

Edited July 19, 2017 by Surfarado

[rhino68]

Update

 

After taking my truck in Monday and showing them the out of round axles, I just got a call from the dealership who to my surprise completely agree with me that they are poorly manufactured and are installing new ones as well as bearings. I should have my truck back today. Just a little amazed that i got absolutely no push back at all. Hopefully it fixes my issues.

 

Awesome. Hope this fixes it for you

 

This has been brought up in the past and only a few people have opted to spend the money to put in a set of Yukon axles or machine the factory axles and the results have been mixed. Not nearly enough data to say whether or not it helps. As far as vibrations are concerned they consist of 3 components the actual mass of the imbalance the distance of the mass from the rotational axis and the angular frequency or RPM at which the assembly turns. So in this case a 1/4 ounce located on the hub 3 inches from the center has little influence compared to say a quarter of an ounce 15 inches from the center like the edge of the tire.

 

in the video you can see that the edge of axle hub has not been machined and the still is still in its raw state from when it was forged. This makes the axle cheaper to manufacture because it is one less op while the axle is in the machining center getting turned, faced and drilled. The real question is whether or not the majority of trucks produced that don't vibrate have this condition, just because trucks that vibrate have it doesn't mean that trucks that don't vibrate don't have it, which makes investing 3 or 6 hundred dollars depending on whether one or both axles have the issue hard to do. If you have a shop swap out both rears I'm guessing you're looking at somewhere between 800 to 1200 dollars for parts and labor. If you go this route hopefully its worth the investment.

 

 

I agree completely. Ive asked friends and coworkers the same question as to what they think that extra mass so close to the center would cause. I've got a 50/50 mix of answers. If this is the cause the only logical explanation would be that some flanges are left with more mass than others?

[rhino68]

Being that you're down in riverside you have an option not a lot of people have. There is a tire shop in signal hill that trues and balances tires while on the truck. This would take into account any imbalance from from the hubs and rotors that traditional tire balancing can't account for. Nate Jones tire in signal hill is one of the few shops left these days that can still perform this kind of work. It's a lot more common on trucks running large tires like 37's and bigger but it's something to keep in mind and might be worth a shot.

 

 

I will have to look into them and check it out. Definitely worth a trip for me.

Edited July 20, 2017 by rhino68

[kthomas72]

Picked up my truck last night from the dealership and wouldnt you know it, no difference. If there was any difference it is ever so slight. Now i need to jack up my truck and look at the "new" axles that were installed just to check. Im starting to believe that its the transmission, I have replaced axles/bearings, tires, adjusted pinion angles, built new driveshaft, lifted then lowered my truck and it still feels like a POS. Funny too because the service manager that helped me at the dealership drives a new F-150 haha, go figure.

[abominable z71]

Picked up my truck last night from the dealership and wouldnt you know it, no difference. If there was any difference it is ever so slight. Now i need to jack up my truck and look at the "new" axles that were installed just to check. Im starting to believe that its the transmission, I have replaced axles/bearings, tires, adjusted pinion angles, built new driveshaft, lifted then lowered my truck and it still feels like a POS. Funny too because the service manager that helped me at the dealership drives a new F-150 haha, go figure.

I've exhausted looking at wheels, tires, hub, rotors, drive shafts, axles, rear end R & P, springs and shocks. I sometimes think transmission even though the vibration isn't changed at constant speed whether in 4th, 5th or 6th gear and my reason for this is:

1. Sometimes the vibrations are terrible while other times on the same stretch of highway at the same speed they are gone or hardly noticeable which is rare but it does happen. Which makes me think something in the controls like lock-up or slip control on the TC.

2. This is the most recent thing I've noticed and it happened today on a 70 mile drive down freeway 99 between Fresno and Visalia not sure if you or rhino are ever this far north on 99 but this section has been redone recently for the 3 lane widening and is buttery smooth. Anyways the truck is riding perfectly smooth at 75 mph. I lay into the throttle to get around some cars RPM's up above 4500 get around everything slowdown from about 90 back to 75 MPH and the truck is shaking about as bad as normal. I've been following this shit show since page 1 and quite a ways back a member had a 14 silverado with the shake, trade assisted out of it and into a 15 sierra that also started to shake and ultimately got rid of it and got something non GM. in one of their last posts they said the truck would start shaking above 68 MPH which we all know to well but they also said that regardless of what speed they were going they felt the exact same shake anytime the truck was above 4500 RPM.

3. Sometimes the truck feels like it is a lot more effective at getting power to the ground meaning accelerating with the rpms in the 3500 to 4000 range the transmission feels tight like everything the motor is sending is getting to the tires other times it feels like a transmission with 250000 miles on it just leaking power through slippage of its internals. not sure if anyone else has noticed things like this. I'm not sure if blackbear performances data collector they use for writing custom tunes can monitor things that are going on with the tranny to see if there is something going on that is creating these conditions. I've though about contacting them to see what they say but haven't got around to it. Right now I'm at the point I just want to get rid of the truck get something else and never consider purchasing another GM product.

[rhino68]

 

 

I've exhausted looking at wheels, tires, hub, rotors, drive shafts, axles, rear end R & P, springs and shocks. I sometimes think transmission even though the vibration isn't changed at constant speed whether in 4th, 5th or 6th gear and my reason for this is:

1. Sometimes the vibrations are terrible while other times on the same stretch of highway at the same speed they are gone or hardly noticeable which is rare but it does happen. Which makes me think something in the controls like lock-up or slip control on the TC.

2. This is the most recent thing I've noticed and it happened today on a 70 mile drive down freeway 99 between Fresno and Visalia not sure if you or rhino are ever this far north on 99 but this section has been redone recently for the 3 lane widening and is buttery smooth. Anyways the truck is riding perfectly smooth at 75 mph. I lay into the throttle to get around some cars RPM's up above 4500 get around everything slowdown from about 90 back to 75 MPH and the truck is shaking about as bad as normal. I've been following this shit show since page 1 and quite a ways back a member had a 14 silverado with the shake, trade assisted out of it and into a 15 sierra that also started to shake and ultimately got rid of it and got something non GM. in one of their last posts they said the truck would start shaking above 68 MPH which we all know to well but they also said that regardless of what speed they were going they felt the exact same shake anytime the truck was above 4500 RPM.

3. Sometimes the truck feels like it is a lot more effective at getting power to the ground meaning accelerating with the rpms in the 3500 to 4000 range the transmission feels tight like everything the motor is sending is getting to the tires other times it feels like a transmission with 250000 miles on it just leaking power through slippage of its internals. not sure if anyone else has noticed things like this. I'm not sure if blackbear performances data collector they use for writing custom tunes can monitor things that are going on with the tranny to see if there is something going on that is creating these conditions. I've though about contacting them to see what they say but haven't got around to it. Right now I'm at the point I just want to get rid of the truck get something else and never consider purchasing another GM product.

 

 

You are correct. You're words are spot on with what I feel. Even with a spindle lift up front and 34" tires my symptoms are the same as those who are stock. I installed the lift and tires at 8000k miles. It was after I installed the lift I started to feel the vibration. I kept going back to the shop telling them I have a bent wheel, pinion angles are off, bad tire, etc. They did everything in their power to figure it out. After coming on here I realized it probably has nothing to do with any of that. As Abominable description of his vibration is exactly what most of us have.

 

After I installed the lift I uploaded my tune from BlackBear performance. First off their tunes are just awesome!. I also opted to keep AFM enabled. The truck feels so much more alive. So after I installed the 1st tune the vibration went away completely. Not one single shake or shimmy. After a couple thousand miles I asked blackbear if they could pull back a little on the throttle response. Without hesitation they did exactly what I wanted and emailed me my new tune. I uploaded it to the truck and the vibration was back. Throttle response was exactly what I had asked for though. I emailed blackbear about the vibration and he requested that he set the converter slip to 0. I wish I still had the email with his explanation. Basically described that our torque converters are always hunting for a certain degree of slip between 0 and 20 I believe... I could be wrong but it was something along those lines. Anyways I uploaded tune 3 and it made a huge difference in the vibration. I'd say 90% of it was gone for about 500 miles and then it came back. So the torque converter or programing could have a lot to do with it as well. After this I was thinking it was the AFM so I had blackbear again do a 4th tune for me that was the same as the 2nd tune just with AFM disabled. Loaded that tune and nothing changed. At this point they asked if I could record a file for them at the time when it shakes. He wanted to go over all the PIDs and whatnot and see what could possibly be changing when it starts to vibrate. I have been meaning to do this and send it to them. I should probably get this together and see If they can notice anything off.

 

I can't remember who it was who posted a link to TSB's about 2 pages back or so but there is one that sticks out to me.

https://www.revbase.com/BBBMotor/TSb/DownloadPdf?id=194276

 

Re-torque the bolts on the trans mount to the engine. Might be worth a try. If i get time I'll see what I can do. Kinda makes sense as kthomas described from seeing in his GoPro video of the trans moving all over the place.

 

Also I've been following this thread for a pretty long time as well. I do remember on member had his torque converter replaced and his issue went away. Has anyone else done this? Thinking before all that work what if a friction modifier was added to the trans fluid first just to see what that does. Could possibly be slipping or shuddering at lock up. Maybe something like this:

http://www.lubegard.com/~/C-230/Instant+Shudder+Fixx

Edited July 21, 2017 by rhino68

[Gears and Gadgets]

158 miles after I left the shop and the vibration is baaaaack!!! The recent repairs have been:

 

1.) Rotate Tires.

2.) Tell me its fixed and call me a liar who should have balanced his tires.

3.) Waste my time and have me come in for a road test with a mechanic where it still vibrated and I told them to continue diagnostic.

4.) Dealer runs Pico Scope, gets no vibration (even after witnessing it while driving with me).

5.) Calls me in to take me for a test drive to show me its fixed. I asked what they had done to it since the last test drive where they tell me "nothing" and send me off with my truck.

6.) 158 miles later and I am getting the vibration again.

 

 

 

[abominable z71]

 

 

 

You are correct. You're words are spot on with what I feel. Even with a spindle lift up front and 34" tires my symptoms are the same as those who are stock. I installed the lift and tires at 8000k miles. It was after I installed the lift I started to feel the vibration. I kept going back to the shop telling them I have a bent wheel, pinion angles are off, bad tire, etc. They did everything in their power to figure it out. After coming on here I realized it probably has nothing to do with any of that. As Abominable description of his vibration is exactly what most of us have.

 

After I installed the lift I uploaded my tune from BlackBear performance. First off their tunes are just awesome!. I also opted to keep AFM enabled. The truck feels so much more alive. So after I installed the 1st tune the vibration went away completely. Not one single shake or shimmy. After a couple thousand miles I asked blackbear if they could pull back a little on the throttle response. Without hesitation they did exactly what I wanted and emailed me my new tune. I uploaded it to the truck and the vibration was back. Throttle response was exactly what I had asked for though. I emailed blackbear about the vibration and he requested that he set the converter slip to 0. I wish I still had the email with his explanation. Basically described that our torque converters are always hunting for a certain degree of slip between 0 and 20 I believe... I could be wrong but it was something along those lines. Anyways I uploaded tune 3 and it made a huge difference in the vibration. I'd say 90% of it was gone for about 500 miles and then it came back. So the torque converter or programing could have a lot to do with it as well. After this I was thinking it was the AFM so I had blackbear again do a 4th tune for me that was the same as the 2nd tune just with AFM disabled. Loaded that tune and nothing changed. At this point they asked if I could record a file for them at the time when it shakes. He wanted to go over all the PIDs and whatnot and see what could possibly be changing when it starts to vibrate. I have been meaning to do this and send it to them. I should probably get this together and see If they can notice anything off.

 

I can't remember who it was who posted a link to TSB's about 2 pages back or so but there is one that sticks out to me.

https://www.revbase.com/BBBMotor/TSb/DownloadPdf?id=194276

 

Re-torque the bolts on the trans mount to the engine. Might be worth a try. If i get time I'll see what I can do. Kinda makes sense as kthomas described from seeing in his GoPro video of the trans moving all over the place.

 

Also I've been following this thread for a pretty long time as well. I do remember on member had his torque converter replaced and his issue went away. Has anyone else done this? Thinking before all that work what if a friction modifier was added to the trans fluid first just to see what that does. Could possibly be slipping or shuddering at lock up. Maybe something like this:

http://www.lubegard.com/~/C-230/Instant+Shudder+Fixx

 

Wouldn't that be something if a little tube of lubegard solved the problem?

[rhino68]

Wouldn't that be something if a little tube of lubegard solved the problem?

 

Chevy would be like Oprah... You get a free tube, and you get a free tube...

[BO TIE 1]

 

Chevy would be like Oprah... You get a free tube, and you get a free tube...

Ok so who is going to be the test rat?

 

Sent from my SM-G935V using Tapatalk

[rhino68]

Ok so who is going to be the test rat?

 

Sent from my SM-G935V using Tapatalk

I'm not sure it would be the torque converter due to the vibration is with speed and not rpm. 4,5,6 gears all have it at 70+ mph. Also felt in neutral going down hill.

[hf219]

I've been getting posts on this page for almost three years now. I just can't wait to get rid of this truck. I hate learning the hard way. Almost three years and no one has an answer, dealership doesn't care, GM doesn't care, salesman only wants to sell me a new truck to fix the problem. I'm just glad that I leased the truck and have an out in the distant future.

[Sir Dan]

 

Awesome. Hope this fixes it for you

 

 

 

 

I agree completely. Ive asked friends and coworkers the same question as to what they think that extra mass so close to the center would cause. I've got a 50/50 mix of answers. If this is the cause the only logical explanation would be that some flanges are left with more mass than others?

I agree that a variation in mass that close to center wouldn't necessarily cause much vibe. But how about a wobbly axle flange. I imagine the tire contact patch on these wide low profile 20s has some influence there and if its jumping from side to side that's a problem.