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Posted

I experience this with my Silverado anyone else?

 

 

A small vibration may be experienced through sweeping turns at highway speeds on some 2015 Colorado and Canyon models. The vibration goes away once the roadway straightens out.

 

This condition is called Smooth Road Shake. The Power Steering Control Module (PSCM) has a calibration to lessen the effects of Smooth Road Shake. However, the calibration is inhibited when the steering wheel is turned beyond a certain degree, at which point the vibration may be felt in the vehicle.

 

Do not replace any parts for this condition. A revised calibration is available that increases the amount of degrees from center that the steering wheel can be turned before inhibiting the Smooth Road Shake correction. Program the Power Steering Control Module with the latest calibration available in TIS2Web and verify the repair.

 

If a vibration still exists after the Power Steering Control Module calibration has been updated, continue with the appropriate vibration diagnostics in the Service Information

Posted

I experience this with my Silverado anyone else?

 

 

A small vibration may be experienced through sweeping turns at highway speeds on some 2015 Colorado and Canyon models. The vibration goes away once the roadway straightens out.

 

This condition is called Smooth Road Shake. The Power Steering Control Module (PSCM) has a calibration to lessen the effects of Smooth Road Shake. However, the calibration is inhibited when the steering wheel is turned beyond a certain degree, at which point the vibration may be felt in the vehicle.

 

Do not replace any parts for this condition. A revised calibration is available that increases the amount of degrees from center that the steering wheel can be turned before inhibiting the Smooth Road Shake correction. Program the Power Steering Control Module with the latest calibration available in TIS2Web and verify the repair.

 

If a vibration still exists after the Power Steering Control Module calibration has been updated, continue with the appropriate vibration diagnostics in the Service Information

hmmm, if you don't mind me asking, where did you find this? I can't specifically say that I have noticed any increase in vibration during turns as it always vibrates, but I also haven't been looking for it., I have pretty much come to the conclusion that it's always going to vibrate. I'll pay more attention to it when on the highway tomorrow to see if I notice it increase during turning.

Posted

 

Most mfg's suffer from a little vibration around cylinder deactivation/activation. Our Rams do it a little as well. The two Chevy's that were the worst were v6's. The vibration was horrible. You could obviously throttle out of it and avoid it, but it ultimately led to a buy back with one customer.

 

From what I have seen, there is no cure for the AFM vibration. I don't hear a lot of complaints on that one, but it does rear it's ugly head from time to time; just not to the extent of the drivetrain issues that are going on.

 

 

 

 

 

I have to say that my 2015 Sierra 1500 CC with 5.3 has no noticeable vibration or shudder or anything when switching in or out of AFM. The only way I can tell is to look at the information display in the dash.

 

From what I gather, you can force it to not invoke AFM by putting the transmission in M5, so if you think that any vibration is caused by AFM, running it in M5 will let you concentrate just on other sources of vibration.

Posted

http://sandyblogs.com/techlink/?p=2568

 

This has all sorts of stuff GM.

 

The one posted above is for a Colorado but we have the same electronic assist power steering.

 

Smooth road shake software is applied to our vehicles as well.

hmmm interesting, seems a little fraudulent to me...

 

 

I have to say that my 2015 Sierra 1500 CC with 5.3 has no noticeable vibration or shudder or anything when switching in or out of AFM. The only way I can tell is to look at the information display in the dash.

 

From what I gather, you can force it to not invoke AFM by putting the transmission in M5, so if you think that any vibration is caused by AFM, running it in M5 will let you concentrate just on other sources of vibration.

even is V6 mode, there is a very slight shake

Posted

"Smooth road shake" really! Sounds like just another made up GM fault condition to justify the incompetence of their engineers. "Smooth road shake" that's hilarious, so now vehicles are suppose to shake and vibrate on smooth roads, it even sounds stupid when you say it.

Posted

Direct from the GM Engineering teams

 

 

The belt-driven electric power steering system features an integrated electromechanical power steering unit, containing the power steering control module, its sensors, the power steering motor, a belt drive and a ball nut mechanism.

The power steering control module is part of the power steering assist motor assembly and is replaceable as a complete unit independent of the steering gear assembly. The torque sensor is integrated with the steering gear pinion and is serviced as part of the steering gear.

The power steering control module has a software feature referred to as Smooth Road Shake Compensation that reduces steering wheel vibration caused by an imbalance from the front tire/wheel assemblies. The vibration transmitted to the steering wheel is referred to as Smooth Road Shake and is a phenomenon that occurs only at highway speeds and on smooth roads.The power steering control module employs active controls to sense and reduce the periodic torque component applied to the steering wheel caused by the wheel imbalance force. This software feature will compensate for a specific range of imbalance.If the imbalance is above a certain level, the power steering control module will disable the smooth road shake compensation and set DTC C044B (Steering Assist Smooth Road Shake Compensation Disabled Too Many Transitions) to indicate that it has been disabled.

In addition to smooth road shake, road crown is compensated for by the steering wheel angle sensor signal, which calculates the intended driving direction.The Electronic Brake Control Module (EBCM) receives serial data message inputs from the steering wheel angle sensor.

The steering wheel angle sensor does not require centering often.However, if the steering wheel angle sensor is not correctly centered it may create a lead/pull condition.If this condition is encountered, always perform the Steering Angle Sensor Centering procedure in SI before performing a wheel alignment.

Posted (edited)

Direct from the GM Engineering teams

 

 

The belt-driven electric power steering system features an integrated electromechanical power steering unit, containing the power steering control module, its sensors, the power steering motor, a belt drive and a ball nut mechanism.

The power steering control module is part of the power steering assist motor assembly and is replaceable as a complete unit independent of the steering gear assembly. The torque sensor is integrated with the steering gear pinion and is serviced as part of the steering gear.

The power steering control module has a software feature referred to as Smooth Road Shake Compensation that reduces steering wheel vibration caused by an imbalance from the front tire/wheel assemblies. The vibration transmitted to the steering wheel is referred to as Smooth Road Shake and is a phenomenon that occurs only at highway speeds and on smooth roads.The power steering control module employs active controls to sense and reduce the periodic torque component applied to the steering wheel caused by the wheel imbalance force. This software feature will compensate for a specific range of imbalance.If the imbalance is above a certain level, the power steering control module will disable the smooth road shake compensation and set DTC C044B (Steering Assist Smooth Road Shake Compensation Disabled Too Many Transitions) to indicate that it has been disabled.

In addition to smooth road shake, road crown is compensated for by the steering wheel angle sensor signal, which calculates the intended driving direction.The Electronic Brake Control Module (EBCM) receives serial data message inputs from the steering wheel angle sensor.

The steering wheel angle sensor does not require centering often.However, if the steering wheel angle sensor is not correctly centered it may create a lead/pull condition.If this condition is encountered, always perform the Steering Angle Sensor Centering procedure in SI before performing a wheel alignment.

 

doesn't this make you miss the old cars where there wasn't all these electronics to screw things up? ohh and I feel like this is a load of... well you know

Edited by Jesse D
  • Like 1
Posted

Truck is at the shop again today. They are going to analyze with a vibration meter.

I specifically stated the speed of vibration was 70 to 75 on highway.

Vibration feels like it starts in steering wheel then feels like it moves to rear or the front is so bad it resonates the whole vehicle.

It seems worse right before it kicks in and out of AFM.

 

AFM is horrible and I am being told nature of the V6 with AFM, I don't believe that at all. When AFM is on the whole vehicle shakes.

 

I also am getting vibrations in highway turns which is similar to the Canyon Colorado problem which can be fixed with software update for "Smooth Road Shake Compensation". I asked them to review my software to see if there is a bug or sensor failure.

 

I have 21000 miles on this vehicle and have been battling little vibrations since the get go, over the last 2 months it seems to have gotten worse.

 

I should prepare myself for the inevitable "cant replicate", "they all do this", or " we can't go over 70mph".

Posted

My patience is wearing thin. I finally made a call to our GM rep and had a less then calm conversation. Yesterday was the 4th time my truck was in the shop and I swear it's worse now than when it went in. They have no idea how to fix it and at this point we are just throwing parts at it. It seems we are all in guinea pig mode.

 

I told my rep it's pretty bad PR for Chevrolet when the GSM for a Chevrolet dealership is dealing with a nightmare truck.

 

Chevy asked me for one more try. It's not going to do any good but whatever, it's their money.

Posted

Truck is at the shop again today. They are going to analyze with a vibration meter.

I specifically stated the speed of vibration was 70 to 75 on highway.

Vibration feels like it starts in steering wheel then feels like it moves to rear or the front is so bad it resonates the whole vehicle.

It seems worse right before it kicks in and out of AFM.

 

AFM is horrible and I am being told nature of the V6 with AFM, I don't believe that at all. When AFM is on the whole vehicle shakes.

 

I also am getting vibrations in highway turns which is similar to the Canyon Colorado problem which can be fixed with software update for "Smooth Road Shake Compensation". I asked them to review my software to see if there is a bug or sensor failure.

 

I have 21000 miles on this vehicle and have been battling little vibrations since the get go, over the last 2 months it seems to have gotten worse.

 

I should prepare myself for the inevitable "cant replicate", "they all do this", or " we can't go over 70mph".

Thats really unfortunate, I'm going to try to get to some nice straight aways tomorrow to do a little testing on mine, Today I noticed that when I was trying to cruise on the highway at about 45-55 MPH the whole cab was shaking, and in a different manner than I previously noticed when the AFM kicks on and off. I also had it happening when trying to do a hard acceleration from the range of 35-50 MPH. Once I got up to 60-70 there was a slight vibration left in the steering wheel, but nothing like those previously mentioned. I can't even begin to say how disappointed I am in this truck. I have already gotten the "cant replicate" for both the radio and the shaking, yet I now have it going back again for both of them, If they aren't resolved this time, which I know they wont be, I'm going to look into asserting the Lemon Law with it, and if they tell me I can't, I'm going to look into trading it in.

 

My patience is wearing thin. I finally made a call to our GM rep and had a less then calm conversation. Yesterday was the 4th time my truck was in the shop and I swear it's worse now than when it went in. They have no idea how to fix it and at this point we are just throwing parts at it. It seems we are all in guinea pig mode.

 

I told my rep it's pretty bad PR for Chevrolet when the GSM for a Chevrolet dealership is dealing with a nightmare truck.

 

Chevy asked me for one more try. It's not going to do any good but whatever, it's their money.

Gotta agree with you there, and I can't help but notice that you have taken down the picture of your truck... Are you getting rid of it? I can't say I'm a fan of this whole "guinnea pig" mode as you call it. You had said that you also run service on Ram, if you are getting rid of the Chevy, what will your replacement be and why? I just feel that when you pay this much for something, it should be working properly, and we shouldn't be getting the "thats just the way it is" bullsh*t"

Posted

After conversation with Service manager, they all seem to do it. Normal. No fix from GM.

 

He is also my best friend and his back is against the wall on this. He is not going to troubleshoot something that GM screwed up on his dime. They have others that have the same issues.

 

They did not even hook up vibration analysis equipment.

 

He suggested a different dealership. This sucks. I may open a claim with GM now as I am in a lease with a truck that is unbearable to drive.

Posted

After conversation with Service manager, they all seem to do it. Normal. No fix from GM.

 

He is also my best friend and his back is against the wall on this. He is not going to troubleshoot something that GM screwed up on his dime. They have others that have the same issues.

 

They did not even hook up vibration analysis equipment.

 

He suggested a different dealership. This sucks. I may open a claim with GM now as I am in a lease with a truck that is unbearable to drive.

Does this mean we should call them Government motors again? It's not like neither GM nor the government can get anything fixed and working properly. hahaha sorry had to make that joke, GM should be embarrassed with the quality of this crap they are putting out, and their own ability to fix the problems.

  • Like 1
Posted

After conversation with Service manager, they all seem to do it. Normal. No fix from GM.

 

He is also my best friend and his back is against the wall on this. He is not going to troubleshoot something that GM screwed up on his dime. They have others that have the same issues.

 

They did not even hook up vibration analysis equipment.

 

He suggested a different dealership. This sucks. I may open a claim with GM now as I am in a lease with a truck that is unbearable to drive.

They don't all do it, only the ones with defective ring and pinions, drive shaft assemblies, tires, wheels, or a combination thereof. There is a fix if GM and/or the dealer want to go through the vibration analysis process. If neither the dealer nor GM will help, then I'd be working through the lemon law process right away.

Posted

GM repurchased my 2014 Silverado LTZ for the vibration issue, It was a very, very painful experience. First they wanted to replace it but I could not find another vehicle with the same MSRP. I had a 0% loan and wanted to do a colateral substitute and not refinance and I also didn't want to give GM another dime. I found a GM Sierra the same options as my truck but it was $4k different and GM wouldn't make the switch. I even tried to build a new vehicle with the same options as mine and the MSRP was more. I also went to the dealership and drove 7 GM trucks (Silverado's and Sierras) 5 of the 7 had the vibration issue.

 

Well long story short they made me an offer to buy back my vehicle and screwed me out of $4700 on my trade in. They gave me a bunch of bullsh!t about the trade in $ being funny money. Well I took the offer and am now driving a 2015 RAM 1500 Larimie and have been very happy with it.

 

BTW... the dealer gave me a copy of all the paperwork they received from GM and it states in the paperwork " Reason for repurchase - Transmission Vibration"

 

I have never felt so victimized in my life as I have been with GM. I have owned 16 GM vehicles in my life and I will never buy another one.

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