Spring Clamps Reduce Rear Vibration

DALaws · April 13, 2016

What do you think these marks mean? This is how I found it when it came out of shop when they told me all was okay. Well it's not, but was wondering what these marks are, and what were they trying to do>

Edited April 13, 2016 by DALaws

LongrangeLauber · April 13, 2016

20160411_161947 (3).jpg

What do you think these marks mean?

I think the line is to show what side of the pinion to line it up with AKA how it is clocked on the pinion and the letters probably signify to the technician who balanced the driveshaft

14silverado4.3 · April 13, 2016

20160411_161947 (3).jpg

What do you think these marks mean? This is how I found it when it came out of shop when they told me all was okay. Well it's not, but was wondering what these marks are, and what were they trying to do>

What vibration do you have DA? Seat or Steering wheel?

DALaws · April 13, 2016

What vibration do you have DA? Seat or Steering wheel?

I know for sure I feel it in the steering wheel. But, there is also times when I hear the rear seat belt rattling, so I can only assume the vibration is being transmitted from the rear to my steering wheel? Also interesting to note. .there was no documentation on any of my service tickets regarding balancing drive shaft? Supposedly replaced all tires and RFB's. Still vibrated. Took it back and RFB'd yet again. They claim they PICO'd it and was within GM Spec. on recently paved asphalt, but said readings will be higher on concrete roads ie, 98% of the roads that have not been recently paved. GM considers the case to be closed since they got vibration is Spec. on a super smooth asphalt road. Have a nice day Mr. customer, glad we could help, now go away.GM is just trying to wash their hands of this. It's unbelievable to me to me how GM is dealing (rather not dealing) with this obvious problem.

KLRV6 · April 13, 2016

KLRV6, I brought this up before but not a lot of responses. I have a lot of Steering wheel shimmy and just crap ride from the front. Have you heard of spring oscillation? Was wondering if the shocks just don't have enough dampening design that allows the front coil springs to start to resonate... Would be neat to see that video?

These trucks transmit vibration, was never as evident as feeling a rear vibration only to find the left front out of balance.

The electronic power steering software allows for a certain amount of out of balance but it has to make its way out somewhere.... if it isn't the steering wheel it will travel elsewhere.

I shot this today. Only up to 60 mph though. Will try to get one 70-80 this weekend.

Ron.s · April 14, 2016

I measured my u-bolts and the thread diameter is 9/16". A grade 5 u-bolt is 90ft/lbs. Mine weren't even at 30ft/lb breaking force which is 3 times less than it should have been.

Question....The bolt itself measures 1/2" so shouldn't max torque be 65#? If these are cold rolled 1/2" with 9/16 thread then the bolt will stretch at that theoretical max. Since we are testing an installed bolt and haven't applied never seize or other lubricant friction might allow a slightly higher torque number but IMO 70# might be the upper limit.

Dnt · April 14, 2016

I shot this today. Only up to 60 mph though. Will try to get one 70-80 this weekend.

Thanks for posting video "very cool". It may be an optical illusion but at around 6.38 when the tire just starts to turn it looks like the tire tread is not square with the wheel and is wobbling a bit. That is what my vibration feels like "a tire". Makes you wonder if these larger size and width tires that have become so popular on new vehicles might be partly to blame, it would seem to be a real chore for a tire manufacturer to make a tire perfect. Anyway wanted to report i installed the new Gabriel Ultra shocks to replace my rusty ranchos on the rear and drove a day and could tell no difference. Then I installed the leaf spring clamps 5" in front of the axle and can still tell no difference. My truck still has the slight shake at 70 with no apparent change after Torquing of the axle ubolts / new shocks / leaf spring clamps. Seems like I wasted my time and money but the new shiny shocks do look better LOL. Ranchos were both leaking at 57k miles and were very rusty Note that I live in middle TN not the northern rust belt.

650h1 · April 15, 2016

Surprised no one has been able to figure this out yet. How do you make a truck with an "un-fixable" shake? There should only be so many things that it could be...

11bDad · April 15, 2016

The vibration I've been dealing with in the rear of my truck is minor compared to what a lot of you folks have been dealing with, but it's still an aggravation. Truck is vibration free until I reach 72 mph & then there is a slight vibration in the console and seat. It's speed related and did not change when I rotated the tires. Tried the clamps in front of the axle, and that did nothing for the vibration. Moved them 8" behind the axle & there was a very slight improvement. I did however notice that the vibration was less noticeable with a full load of fuel, and the vibration would increase as the fuel was burned. Picked up 2 bags of concrete and put them on either side of the bed by the tailgate. With a full load of fuel, and the concrete, the vibration was almost completely gone. Strange thing is that when I leave for work in the morning, and it's cooler, the vibration is almost unnoticeable, vs when I come home and temps are higher. Next step will be to have the rear tires balanced on the truck & if that doesn't help I'll probably replace the rear shocks with some Bilstein 4600. It's a 2WD, 4.3L, 3.23 rear end with the Z60 package & 20" Continentals. Other than the high speed vibration, the truck rides friggin great.

Dnt · April 16, 2016

Next step will be Road Force Balance when I get my next set of Michelns. Although I did see a Ford platinum the other day that looked really good..............

KLRV6 · April 16, 2016

Next step will be Road Force Balance when I get my next set of Michelns. Although I did see a Ford platinum the other day that looked really good..............

Yea they look good. I would be driving one today, but the 14K difference from where I'm at now with my payment is the absolute, only reason I still have the Silverado..

ChevyRoofer · April 19, 2016

Anyone seen the picture of new denali delivered? Has spacers/dampers between the rear-leafs...

Is this GM's fix for this solution???

Post #29 for picture.

http://www.gm-trucks.com/forums/topic/183339-2016-sierra-denali-2-month-review/page-2

LongrangeLauber · April 19, 2016

Anyone seen the picture of new denali delivered? Has spacers/dampers between the rear-leafs...

Is this GM's fix for this solution???

Post #29 for picture.

http://www.gm-trucks.com/forums/topic/183339-2016-sierra-denali-2-month-review/page-2

I got em, mines a 14 High Country. Only rear suspension modification made is I installed helper springs but they fit over top the leaf pack so no need to take packing apart