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Posted

Rolling tunder - the dealership told me they got no prints from road forced balancing because the machine can’t print results to a printer. So not sure how that works because an independent tire shop told me to ask dealership for printout of results as they said they had issues with Goodyear wranglers the very same one on GM trucks. Like tires were bad from manufacturer to start with. Who knows anymore what’s the cause but like others said GM knows but won’t admit to it. 

Posted

I like a good conspiracy theory as much as the next guy, particularly when it involves the manufacturer of my craptacular 1980 Pontiac that turned me off American cars for over 30 years.

 

That said, it's hard to be sure of how widespread defective driveshafts really are, given how many of these trucks are sold every year.  At these sales volumes it only takes a 0.1% defect rate to create a huge uproar in the forums.  And then there are the cases like mine, where a tire swap or other "quick fix" did in fact solve the problem.   GM was right to suggest it as a first line of attack.  

 

Anyway, I hope the more seriously afflicted owners do find a cure.   Big corporations are driven by economics, always seeking the cheapest possible way around a problem.   The trick is to make it unbearably expensive for them to ignore you.

Posted
4 hours ago, Barak said:

Rolling tunder - the dealership told me they got no prints from road forced balancing because the machine can’t print results to a printer. So not sure how that works because an independent tire shop told me to ask dealership for printout of results as they said they had issues with Goodyear wranglers the very same one on GM trucks. Like tires were bad from manufacturer to start with. Who knows anymore what’s the cause but like others said GM knows but won’t admit to it. 

Barak,

 

I made no reference to 'road force balancing,' my reference was to the PICO tester and its available printout.

 

Your experience with those Goodyear Wranglers is another example of what may solve one owner's issues and not anothers.  When I bought my truck I removed the 20" chrome wheels and installed the default 18" Z71 aluminum wheels with those Goodyear Wranglers.   I never had a vibration then and don't have one now and those wheels and tires carried us to Florida once and Alabama twice on the 70MPH+ Interstates.  I've seen many complaints about the Wrangler tires here but I never had any issues with them.

 

I've had the 18" wheels conventionally balanced independently by a private shop after the exchange, not a road force balance, and the factory balance left a lot to be desired.  I personally have no idea what causes the vibration on a small percentage of these GM trucks but it's a helluva thing to read about the problem on $50,000 +/- trucks and the understandable dissatisfaction of those owners.

Posted
22 hours ago, Barak said:

LoL what a process. Well interesting enough I have to say that I have not been noticing vibration at 72-75 speeds anymore. It’s strange but it’s no longer apparent like before. I did sort of feel it at higher speeds like 85-95 but that could be due to cross winds etc especially going that speed. However, the dealer should be reaching out back to me to work on service bulletins once they have PICO tool in thier hands. So we will see what that comes to. I do feel that a real shake/vibration is at driveshaft area. And it’s not uncommon for engineers to come out and enage. Hopefully by having engineers due this maybe GM will come out with a fix and recall. Let see what happens. Keep posting please. Thanks! 

I got a 2016 Suburban February and it doesn't vibrate until I hook up a trailer, shakes worse when towing on fresh blacktop then concrete, when I towed my tractor back from cabin in north WI a few weeks back it didn't shake. Your comment got me thinking, aluminum absorbs heat, and when it is hot there is less strength to it, could it be that blacktop is much hotter then concrete and we have much colder weather here now?  Hot driveshaft is weaker then a cold one?

Posted

Interesting perspective. I hope GM is reviewing and listening to these experiences we are all having. The driveshaft hot/cold makes lot of sense given weather conditions in certain parts of country unless it’s tires or any other suspension components which seem to be first things GM suggests to look into and rule stuff out. 

Posted

I’ve recently encountered this “infamous” shake or vibration but mine is more around 1250 rpm. Doesnt really matter the speed but it’s more when I’m speeding up staying at  1250 rpm it’s constant so I have to give it more gas to get out of the “shake”. Has GM solved any of these issues? Or given answers to what’s at fault?

Posted

Nope.  They are staying quiet about it and no matter what amount of noise the public makes, they seem to be able to muffle it.   They and other manufacturers will just ignore the issue or put it on the back burner and hope the new model doesn't have the same issue and focus on the new model instead of doing the right thing to make right the screwed up engineering somewhere for the many thousands of people who have the issues. 

Posted

You’ve got the torque converter slip. I have it on both my vehicles. I’ve had the flush, the valve spring replacement, new engine mounts, and they replaced the TC. Still an issue. My dealer said they are working on designing a new TC and will replace via recall. Don’t hold your breath. 

Posted

Text from the dealer today said - GM engineers recommended that we take the driveshaft to a shop to have it checked and balanced. 

 

Fingers crossed this actually could fix it 

Posted (edited)

The more I read the more I question my situation. I have a 18 Suburban, my first red flag was the excessive vibrations when at highest speed, too it in and the balance my tires problem seemed to be better. Next I went in for a headline issue and mentioned vibrations so they road force balance them and replaced one tire. Just drove 350 miles around 70-90mph and it felt like excessive bouncing like suspension was over working. I didn't feel like the whole car was shaking like my first time I noticed this issue. My experience is that 50+mph it feels like I'm driving in a cobblestone street. 

Does anyone know what GM "within specs" are for road force balance. I just had my 2018 Suburban road forced and the numbers they said seen higher than I recall my previous cars have had. They replaced one tire but I still have vibrations.

 

 

Edited by Dearmosd
Posted (edited)
13 hours ago, Dearmosd said:

Does anyone know what GM "within specs" are for road force balance. I just had my 2018 Suburban road forced and the numbers they said seen higher than I recall my previous cars have had. They replaced one tire but I still have vibrations.

My experience is that 50+mph it feels like I'm driving in a cobblestone street. 

 

 

Under 10LBS is what I was told by my service manager Dearmosd but GM calls for under 15. 

 

 

Edited by GMCJOE17
Posted

When I was a kid I worked in a gas station (50 years ago).  We sold, mounted, and balanced hundreds of tires on cars and trucks.  And through the years I've had lots of cars and trucks that I had tires replaced on after they wore out.  95% didn't have or cause any vibrations.  God bless those that are trying to solve the Chevy vibe issues, but generally it seems to go way deeper than just tires and or wheels.  GM engineers know what the problem is, or problems are, they just aren't letting the cat out'a the bag.

 

Class action might help but what I believe what we really need is for major news organizations (yeah, even the "fake news" folks) to be made aware of the issue and report it.  Make the problem known to the public at large, not just the unsuspecting suckers that buy these trucks.

Posted (edited)

I believe it's the cheap, hollow out of round aluminum driveshafts that are to blame for the shake. I've seen a few people that got steel, 2-piece driveshafts installed and the vibrations were gone.

Edited by ShubiSnax
Posted
2 hours ago, ShubiSnax said:

I believe it's the cheap hollow, out of round aluminum driveshafts that are to blame for the shake. I've seen a few people that got steel, 2-piece driveshafts installed and the vibrations were gone.

Agree, the angle of the shaft to the rear end is an issue plus the cheap Aluminum shaft with Cardboard core is another issue. Trying to balance the tires to PERFECTION may help the balance issue but it wont solve it. Anything GM can do to take the spotlight off the driveshafts and save money you know they are going to do. Imagine a recall on ALL the driveshafts from 2014-2018. 

Driveshaft2.jpg

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