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Posted

Ok guys I have the same issue with my rally 2 with 4000 miles where do I start this sucks

Our 2014 Rally 2 is back in the shop as of this morning. They've road forced the tires a few times, changed all four tires, lubed something that wasn't done when it was built, rebuilt the rear differential, replaced the drive shaft. Luckily we have a dealer that is really working with us. It's been in the shop 5 times now. Biggest improvement was when they rebuilt the deferential. Still vibrates. Be ready to be in it for the long haul. Be nice with the dealership and they'll work with you. If this last trip doesn't fix it we'll be going the lemon law route. Keeping our fingers crossed! Good luck to you!

Posted (edited)

Ok, they pulled and balanced the drive shaft this morning, didn't fix it. They are now looking at the ring and pinion. Parts in tomorrow morning to make the changes. They told me it's defiantly something in the rear end that's causing the vibration.

Crazy thing is, I had zero vibration until about 12,000 miles. Then like a switch it started.

Hope they get it close enough by this Friday as I need the truck this weekend.

Very frustrating to pay this much for a vehicle and it's not 100%.

Looked at a Tahoe LTZ yesterday, might have to dump and run if this doesn't get fixed right.

We also have 22" rims and issues with the back. They completely rebuilt the differential (ring and pinion) and that's where we felt the best improvement. Both readings of the differential and the shaft we WAY off balance from factory. Pretty much the whole truck was built off spec, things weren't lubed where they should have been. I'm wondering what went on when they built ours. It's a Nov. 2014 build. They ordered a brand new shaft built within the last two months and installed that and we didn't feel much of a change after that. Still not fixed though, it's back at the dealer today and the 2015 LT Z71 with 500 miles they gave us as a loaner still has some vibration at highway speeds. We can't win! Edited by Bdkfl
Posted

I wonder how many people have had the body mount service bulletin applied (repositioning and retorquing) on their trucks and whether or not that led to a successful fix.

 

Shimmy, do you have the bulletin handy or happen to know the number? Thanks!

Posted

 

Shimmy, do you have the bulletin handy or happen to know the number? Thanks!

So did you try the body mount re-torque?

Posted (edited)

So did you try the body mount re-torque?

 

I loosened and tightened all of them one by one last night but don't know if it made a difference since I only have a 4 mi commute to work all back roads so haven't had it on the highway yet. I think tonight I'm going to loosen all of them, and the tighten in a diagonal pattern similar to how you would tighten lug nuts. Would love to have the service bulletin to make sure I'm doing the procedure properly. I would try loosening and driving it around a little to get it to resettle but that makes me a little nervous so I will try doing it stationary first.

Edited by hotrodz37
Posted

 

I loosened and tightened all of them one by one last night but don't know if it made a difference since I only have a 4 mi commute to work all back roads so haven't had it on the highway yet. I think tonight I'm going to loosen all of them, and the tighten in a diagonal pattern similar to how you would tighten lug nuts. Would love to have the service bulletin to make sure I'm doing the procedure properly. I would try loosening and driving it around a little to get it to resettle but that makes me a little nervous so I will try doing it stationary first.

Yep was thinking the same thing. But that is what was told to me by the tech/engineer at the shop last week. I didnt know there was a bulletin, I am curious to see this as well. I seem to have the shake in the rear end of the truck. You can see it at 74-80mph in my Snuglid. Seems more like "Beaming" mor than anything.

Posted (edited)

My cab to frame bolts were torqued to 110 lbs from the factory. Lowered them to 70. Best I can say is it may have made a difference. Mine is a 2015.
Joe

Edited by jagabom
Posted (edited)

Hey all might be getting little bad data on the cab mount torque specs. Raptor instructions say 70ft lbs and westin says 95ft lbs. my buddy that is a gm technician will get back with me with what the service manual states

 

http://www.raptorseries.com/installation-instructions/1201-0026M_install.pdf

 

http://www.realtruck.com/shared/pdf/manufacturers/198/75-3023.pdf

Edited by JC84
Posted (edited)

3 main bolts on each side are 122 lb ft. Nuts at front are 52 lb ft. As per GM Service Info.

Edited by tbarn
  • Like 1
Posted

I just read on another site that the middle one is 35 lbs. Thanks JC84 for checking it out for us.

Joe

I second that - Thanks JC, appreciate it! They are definitely 70+lbs each. I checked all of mine yesterday that hadn't been touched since it was new and I put the torque wrench on them before I loosened them and they all clicked at 70ft/lbs. might be more but definitely not under 70. Hope to get some good info soon!

 

Also, I found the cab mount settling procedure. Seems pretty involved:

 

Cab Mount Settling Procedure

Warning: When settling the body cushions, do NOT separate the frame from the body more than is necessary. Possible personal injury and damage to multiple parts may result if you do not follow the guides outlined below:

Intermediate steering shaft—Do not allow the shaft to extend more than 25 mm (1 in).

Fuel tank filler hose—Do not stretch the hose excessively.

Tail/Turn signal lamp wiring/rear lamps junction block—Leave slack in the wires

Park brake cable—Leave slack in the cable.

Body ground straps—Leave slack in the wire

The technician should first loosen the fastener located at the center of each body mount (6 for a regular cab, 8 for crew and double cab).

Using a large angled pry bar, lift up the cab body slightly to settle / relax it. Perform this at each mount location one at a time.

Repeat this cab mount settling process twice, to confirm the mounts are settled / relaxed.

Visually verify that the cab to box alignment is correct before re-torquing all mounts to specification found in Service Information, body repair, frame and under body section.

 

 

Sent from my iPhone using Tapatalk

Posted

Hate to hear about your problems and while the shaking sucks how does that show that the truck was "not reliable". Did it break down on you or something?

 

No it didn't leave me stranded and I didn't give it the chance to. Them not knowing what's causing all these truck owners the same issues. ... to me screams unreliable.

Like I said ... I liked my truck...my experience along with many others on this topic has been apparently different than yours.....and I'm glad for you.

 

Posted

Hey all might be getting little bad data on the cab mount torque specs. Raptor instructions say 70ft lbs and westin says 95ft lbs. my buddy that is a gm technician will get back with me with what the service manual states

 

http://www.raptorseries.com/installation-instructions/1201-0026M_install.pdf

 

http://www.realtruck.com/shared/pdf/manufacturers/198/75-3023.pdf

 

JC, I was thinking last night. Do you think your vibration could have been from the steps themselves vibrating in the wind, and when you took them off it fixed it? Just a thought, but hoping it was the actual re-torquing of the body mounts that did it (hoping for my case anyway).

Posted

I was thinking the same thing. Couldnt figure out why he removed the running boards to re-torque.

Posted

I have a 2014 z71 that was bought back by Chevrolet as they claimed to fix the vibration I still have. I purchased knowing it had been an issue at 50 mph, but I was told the problem had been resolved.

I know the dealer I bought it from but would be more comfortable bringing it to another dealer to look at.

Any thoughts on this process?

I did sign an acknowledgementioned that I was made aware of the issue and that another year was added to warranty.

thanks. I did pay far less than market UT just want the vibration to

go away

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