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Posted
Svtkidd...by the looks of that graph you were taking a measurement while getting the truck up to 65mph. The key for vibration analysis is to hold a constant speed and then take the reading. I see on the graph you have a lot going on in the 3500-5000 rpm range...someone correct me if i'm wrong but the only thing on the truck spinning that fast would be the motor...unless u were doing somewhere around 160 mph then maybe a driveshaft...

 

Rpm has nothing to do with my truck that's the vibrations in phone

And that was constant speed going off 3 vibration sensors x y axis and mean

 

 

Sent from my HTC6500LVW using Tapatalk

 

 

Posted

I took my truck in for the third time yesterday. Shop foreman went for a ride with me. He said yes I feel it too. And it's a tire issue. They are gonna try again to balance the tires. He also said this is the third set of tires that's been on my truck. And if they can't fix it this time I may just be stuck with it. Said today's new tires are harder and they ride rougher. I said you mean my new $45k truck is just gonna have to ride worse than my daughters 02 ford escape? He really didn't have an answer for that. I have been nice up to his point, but if its not fixed this time!!! I can assure that I will get someone's attention !!!!!

Posted

I took my truck in for the third time yesterday. Shop foreman went for a ride with me. He said yes I feel it too. And it's a tire issue. They are gonna try again to balance the tires. He also said this is the third set of tires that's been on my truck. And if they can't fix it this time I may just be stuck with it. Said today's new tires are harder and they ride rougher. I said you mean my new $45k truck is just gonna have to ride worse than my daughters 02 ford escape? He really didn't have an answer for that. I have been nice up to his point, but if its not fixed this time!!! I can assure that I will get someone's attention !!!!!

Curious to know what dealership you're dealing with...?

Posted

Not to give names, but a gmc dealer on nw expressway :-)

 

 

 

That wouldn't be BH would it?

Posted

I will say that my dealer has been nothin but nice. They give me a loaner to drive while they work on mine. I just wish they would get it fixed.'

Posted

Update: Just dropped my off for the 4th time and the dealer said GM has given them something to try on the Drive Line. Not sure if that is a replacement or what. I think it is the transmission as the vibration can now be felt at 24mph and I have already put new Michelins on. I will post status as soon as I get it back.

Posted

I will say that my dealer has been nothin but nice. They give me a loaner to drive while they work on mine. I just wish they would get it fixed.'

I'll take a rude dealer that fixes the problem first time over a polite one that has no clue what to do.

Posted (edited)

Update: Just dropped my off for the 4th time and the dealer said GM has given them something to try on the Drive Line. Not sure if that is a replacement or what. I think it is the transmission as the vibration can now be felt at 24mph and I have already put new Michelins on. I will post status as soon as I get it back.

If they tell you they are gonna check hub runout and/or rotate the driveshaft 1/2 turn - - be aware both of these "GM" recommendations were performed on my '14 Sierra DC and did not help! The installation of new Bridgestones took about 95% of the vibration at 70-75 mph away....

Edited by gjk1932
Posted (edited)

Update: The Goodyear LS-2s were taken off and swapped for Michelins yesterday...I had time to run the truck today up on the highway. What a difference!! The truck runs nice, smooth and quiet....until you take it over 70MPH!!!! ITS STILL SHAKING :dunno: ........I talked to the dealer and let them know the vibrations are still present...in a weird way I actually feel bad for the dealer in that GM left them holding a leaky bag with SOME of these trucks. The dealer told me they did a traditional balance because they do not have the road force balancer.

 

Based upon my latest vibration test, I am convinced its something related to wheel speed however not necessarily the tires. (See the red spike on the attached pic in the 800 RPM range at 75mph.) That spike is on the X-Axis meaning it is a shake from left to right, (driver side to passenger side).


I may pop the wheels off and check the runout on the hubs and rotors with a dial indicator. Can anyone think of anything else that spins at wheel speed that I could easily check while I have it apart? I am open for suggestions!!

post-125975-0-49834500-1389226111_thumb.jpg

post-125975-0-49834500-1389226111_thumb.jpg

post-125975-0-49834500-1389226111_thumb.jpg

post-125975-0-49834500-1389226111_thumb.jpg

Edited by Arnoldthepig

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