Shake or Vibration Issues

[WLC]

No vibs in mine (yet). With so many replies and views you would think someone would come up with a fix! There are smart people at GM that is why they don't have a fix.It would cost GM a boatload of $$$$.Cut their own throats.Now .. Maybe...If .... We if we had a reward of some sort it would up the Annie. Someone knows, they are not telling. ..Maybe start with a vib truck and start stripping her down and adding custom replacement parts until the vibs stopped!...Got any ideas????... Read one post where the truck didn't vib after being jacked up and wheels R +R. Let's figure this out. Think! Think! I have been. Someone be a Hero for this topic!

[LongrangeLauber]

No vibs in mine (yet). With so many replies and views you would think someone would come up with a fix! There are smart people at GM that is why they don't have a fix.It would cost GM a boatload of $$$$.Cut their own throats.Now .. Maybe...If .... We if we had a reward of some sort it would up the Annie. Someone knows, they are not telling. ..Maybe start with a vib truck and start stripping her down and adding custom replacement parts until the vibs stopped!...Got any ideas????... Read one post where the truck didn't vib after being jacked up and wheels R +R. Let's figure this out. Think! Think! I have been. Someone be a Hero for this topic!

Install all aftermarket ring and pinions and let me know if it cures it. Then try gmt900 cab mounts, or vise versa. Those are the only things I can think of the try

[WLC]

Seems like most have vibs around 70mph. That type of wind would tear up a lot of things! Maybe setting up vibs to transfer to other components. There can be many reasons but let's find a solution !

[WLC]

Pump up a hydraulic pusher between frame rails at different locations with different types of isolaters(wood,rubber ect.) Air spoilers in different locations while in wind tunnel. Cold room, hot room while running a Dino with vib truck. Someone spill there guts and let's go to work!

[WLC]

I started page 429. WOW they had power. Anyone drove a 429CJ?

[rshad]

I have not read through all 429 pages of post but is this happening to all engine sizes or just one? So far is thee anything in common like what extras package on the truck or even trailering package and other optional equipment equipment?

[Tattooo]

Seems across the board

[paxtonman]

No but I had a 429 SCJ, and a 351 Pinto, and a 514 67 Fairlane, now I drive Chevy's all because my local dealer supported a new swimming pool in town and the Ford dealer didn't

[pspapa]

ive done a little researching lately because ive been experiencing similar problems with my 2010 silverado. if the truck has an AFM or automatic fuel management system, an economy mode will take over under light acceleration allowing the truck to run on only 4 cylinders. this is where i can feel the vibration in my truck in the steering wheel, gas pedal, and drivers side floor pan.

 

[tnchevy]

I've got the same vibration under very light throttle while in V4 mode which was exaggerated by adding an aftermarket exhaust, that vibration is a change in exhaust flow, not the vibrations people are talking about on this thread.

[67ChevyRedneck]

I had a a 2000 yukon & 04 sierra that never vibed either

 

Same here. I owned a 2000 Z71 for 11 years, bought it at 4 years old. NEVER a vibration. EVER. Not at 2 mph, not at 80 mph, nothing. Ever. Not even at idle, I had friends that would comment at lights "did you truck shut off?" I honestly had to look down a few times myself over the years to see if the tach was at 500rpm or if the truck was actually off. Absolutely LOVED that truck (my sig pic). It never once saw a dealer or shop in 170+K miles. I traded it for the pile of shit I own now.

 

I'm pretty sure my truck is slowing getting worse. Has around 3,500 miles on it now. Same vibration though, only feel it in gas pedal and floor and usually just through shifts and up hills. Not the same as what most people describe. V8 or V4 mode has zero affect on mine.

Edited October 27, 2015 by 67ChevyRedneck

[pm26]

Absolutely LOVED that truck (my sig pic). It never once saw a dealer or shop in 170+K miles. I traded it for the pile of shit I own now.

You got a lot less for a lot more.

[67ChevyRedneck]

You guys are not the only ones. I have the annoying gas petal vibration / buzzing at freeway speeds. Its so odd, at 65 I can't feel it but at 67, 68, 69, 70, ... It increases in intensity and does not go away. I use cruise control a lot due to it. My dealer saw my larger LT AT tires and said we can't test it with those on there. They apparently swapped em out with a different truck on the lot and said pico reading were "within spec" with factory tires and blamed my larger tire, the "weak?" 3.08 rear end and v4 mode for what I was feeling and said nothing could be done about it (like everyone else here they did rebalance my tires though). I get a decent shake on rougher roads too at around 50-55. Not sure if that is more normal and just crappy Rancho shocks or what? I gotta go in for an oil change so I plan to bring it up again this next week.

 

I wouldn't doubt it if my truck "passed" their Pico test as well. I was told the same thing, "it's the truck trying to be efficient" but it does it in V8 mode too under power. Pretty sure its not trying to sip gas going up a hill doing 60 mph.

 

If anyone is curious to what it feels like, put your cell phone on vibrate and put it right next to your feet on the floor, then imagine driving it like that.

 

I wrote a nasty letter to the service manager a few weeks ago and finally got a response last Friday... My other issue is I don't have time to **** around bringing a truck in to the dealer a couple times a week. They want an appointment to see what's wrong with it first, then after that you make another to "fix it."... pain in the ass. They also keep telling me "their out of loaners" because they know they're not going to do dick to my truck.

 

 

Edited October 27, 2015 by 67ChevyRedneck

[OmahaBen]

OmahaBen, on 15 Oct 2015 - 9:51 PM, said:

 

 

I have some news which is very positive. I will start from the beginning.

 

I had my truck in the first dealer at least 6 times, they replaced one wheel, 2 tires and did numberous roadforce balancing. About the 4th trip in they got the pico meter. After driving the truck the service manager said the truck did vibrate but wasn't out of spec according to the pico scope. They did not check the driveline for runout to my knowledge.

 

I don't think this first dealer or tech wanted to spend the time or did not know how to correctly use the pico meter.

 

I was at church and my mentioned the issue to a buddy which works at another GM dealer. He said you should bring it over and we can take a look at it. We have a very thorough tech that has a knack for fixing issues such as yours.

 

So after the first dealer started talking buy back. I thought to myself, can't hurt to have someone I know in my corner.

The first dealer scheduled the regional GM rep to drive my truck, I had to reschedule this because my truck was in the other shop the day he was there.

 

The second dealer. They had my truck the first day and couldn't find anything wrong. The tech did say he felt a very annoying vibration while driving in the 70mph-80mph range. They had to follow GM protocol, they ran the truck one more time with the tech in the passengers seat with the computer and the service manager driving with PICO scope installed. They then sent the readings to GM engineering. After it was deemed my truck was "out of spec" they followed an order of measuring parts. Driveshaft runout, axle runout and axle flange. The checked for bent wheel studs / studs out of pattern. Measuring backlash between each tooth of the ring gear. The pico scope file also told GM there was a wheel tire variation and another possible issue. Then they measured the preload on the pinion. The preload on the pinion was almost zero. none at all!

 

The GM engineer this was escalated to, stated that these tires LS2 Goodyears have had a bunch of bad runs. He sent 4 Brand new tires that where from a known good batch they had on hand to the dealer. In the mean time the gm engineer said to check out the rear shocks and found that both of my rear shocks were toast. I don't know why or how they failed but they were replaced.

Also they found the wrong shim was installed behind the pinion. My truck needed a .050 shim and it had a .045 shim (I think that is the correct measurement as I don't have the sheet in front of me)

The second dealer had my truck for 2.5 weeks mostly waiting for parts, tools or GM approval.

They drove the truck after the new tires were installed, rear end rebuilt, all new bearings and ring and pinion (9.75 rearend) and shocks replaced. They did test with the pico meter installed and the truck ran well within spec.

 

I drove it tonight and it seems like it is fixed. I drove it up to 80-85 and there is no more high speed vibration. The proof will be driving it a long duration and with my trailer hooked up.

 

As of right now I think they got it fixed. After reading all of the horror stories on here I wanted to post some good news.

 

Here is the bad news. GM only pays for so much shop time for warranty work. The dealer said that about 10 hours will not be covered by GM. They will eat 10 hours of shop time and make a GM customer happy. The shit of the deal is I didn't buy my truck at this dealer. Since I had a friend inside I think I got further than most other customers would have. I can't prove this but it is my theory.

 

I am sad because this isn't the dealers problem. GM needs to pay to fix this.

I would suspect that there are a lot of trucks out there with this issue. Because many drivers stay in town and never take long hauls or run the truck past 70mph so they may never even know or detect a vibration. I had 4 different GMC sierras loaners and 3 of the 4 had noticable vibrations above 70mph. The last one being the worst. I truly think the first shop didn't want to start in on the mechanicals because it wasn't worth their time and they didn't want to eat the shop time.

 

I didn't proof read this as I am tired. I hope this helps someone else and I will post a follow up in a couple months after I get 5000 miles on the truck to see if the vibration is truly gone.

 

Have a good one

Update. Another member here asked my update so here is what I told him:

 

I put about 600 miles on it so far.

 

They set the backlash really tight. I hear a coast noise when slowing down I didn't notice before.

 

I have become hyper sensitive to the vibration. Drove about 200 miles the other night and I swear at 75mph I could feel it. I would change lanes or get on a better surface of the interstate and it seemed to go away.

 

If I was at 85% to start. The wheel and road force balance made it 90%. This repair has made it 97.5-98%. (I still think there is something else going on here) Maybe driveline angle, torque convertor or transmission/transfer case issue. (100% being perfect with no vibration)

 

Not sure the vibration is completely gone. Haven't spent enough time at 75-80mph.

 

If I would have gotten the truck the way it is now, I am sure I would have never noticed anything.

 

I have a long haul on the interstate with my trailer so that will be the real test mid November.

 

I would call my truck 98% fixed by the tires and rear differential rebuild. I have close to 1000 miles on the truck (since rearend rebuild and new tires) now and it has stayed the same.

 

The only reason I can't say 100% is because after driving the truck with no noticable vibration it sure seems like my truck picks up a lot of "road feel". Uneven roads, rough roads, roads with lots of cracks or seams. I have never had a truck with 20" wheels before but I don't remember my old 2004 with 17" wheels picking up the road feel like this.

 

When I am on a smooth road everything is fine. When I go down a road that is bad it feels like the vibration is back.

 

I know I have become hypersensitive to the vibration so it is hard to separate the two. Road feel vs. vibration

Edited October 27, 2015 by OmahaBen

[Tattooo]

I guess you can live with a 98% fix