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Posted (edited)

If this is true, GM should be able to hold their supplier accountable for the costs to replace the rear ends, no?

 

Does anyone know if this was a new supplier or a new line for our trucks? Do they make all gear sets or just certain ones?

they changed the method for how they cut the gears. supposedly they went from a 5 step to a 2 step

 

All good....just picked it up and the new tire & road force balance did the trick......

huh? so have you already had it in the shop for vibration?

 

I'm going to start a class action suite against the LT owners who go it for free.

I'll give mine back if they give me full MSRP so I can change brands, I don't like this feature

Edited by Jesse D
Posted

Do they require rear end replacement with 4k miles on the clock?

GM was so much more efficient than that! Truck was delivered with that requirement already built in.

My point, however, is that some of us have been lucky enough to get our vibes fixed. It's one fine truck vibe free.

 

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Posted

If this is true, GM should be able to hold their supplier accountable for the costs to replace the rear ends, no?

 

Does anyone know if this was a new supplier or a new line for our trucks? Do they make all gear sets or just certain ones?

Legally, I believe that GM is responsible for ensuring that parts meet specs before installation. Cutting corners, in this case, is costing GM big time, unless the customer accepts the "performing as designed" b.s.

 

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Posted

Legally, I believe that GM is responsible for ensuring that parts meet specs before installation. Cutting corners, in this case, is costing GM big time, unless the customer accepts the "performing as designed" b.s.

 

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Sure, but if the root cause was a bad batch of parts, GM in theory shouldn't be as resistant to fixing this since they shouldn't have to eat the cost of parts and labour. They should be able to recover the costs from AAM.

 

AAM may not have been cutting corners while cutting gears. This 5 to 2 cut process seems interesting and ironically was designed to reduce nvh.

 

Either way, it looks like GM engaged and have found the issue(s). This is great news.

Posted (edited)

GM has provided the vibration feature as standard equipment on a select number of trucks.

I think on one of there commercials they refer to this feature as perfection .

Edited by TheFactor
Posted

This was discussed before and someone stated that their truck which was repurchased by GM showed up on his dealer's lot as a "certified used vehicle" several weeks later.

 

Buying back to GM means finding another sucker to buy the same truck.

When I was having problems with my Sierra with the frame coating peeling , the CARFAX listed "inspections" and "serviced" when the truck was traded in and hit the used lot. Some other poor sap ended up with a " beautiful like new " Sierra - raining rust from underneath.

If you are buying low mile used- best to ask for the dealer service report on what was actually done.

Posted

Either way, it looks like GM engaged and have found the issue(s). This is great news.

 

 

They have ????? Well what is it, we would all love to know !!!!!

Posted

More than a few reports in this thread of folks that have had their rear end replaced without any improvement at all. Now were they replaced with more defective parts, who knows.

Posted

I'd be interested in knowing what everyone's road force balance numbers are.

they don't matter, they aren't the root of the problem. GM has actually dropped their allowable spec to below industry standard to try to reduce the vibration.... it hasn't worked

Posted (edited)

Still dicking around with mine, waiting for the GM to figure a solution....

 

I still go back to thinking about Electronic Power Steering Software issue..

 

I have good RF on rear tires, Fronts are slightly high with 16 and 21 RF numbers.

 

Getting a slight vibration in fronts on straightaways, highway speed sweeping turns excites the vibrations.

 

According to the Smooth Road Shake Software, it should compensate for slight out of balance conditions.

Why is it not compensating? The following comes directly from GM advertising:

 

Has anyone tried or had their service department reset the software for this?

 

 

Electric Power Steering System

 

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.

 

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

Edited by 14silverado4.3

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