Bad shake in 4hi under acceleration

[s3customs]

Did a search and couldnt find a solution to this problem that others have also had. In 2wd everything is smooth and vibration free. in 4hi there was a bad shake. My first thought as bad as it was that it was a wheel loose. ( i think coming more from the right front ) when accelerating( not hammering on it just normal picking up speed, then goes away when i let up or am just cruising. Changed both cvs today thinking that was the issue ( right one was pretty bad. But to my disappointment the shake is still there, slightly better but still there. I did notice the lower ball joint on that side needs to be replaced, not sure if it would do this or not. Both wheel barrings , outer tie rods , struts and springs have all been replaced over the last six months so i have ruled them out. any help on this would be greatly appreciated

[The Roadie]

4HI on pavement? Have you tried that before and felt driveline binding? Loose ball joint could give you vibration under torque application. How about with the 5% torque you get in A4WD mode on pavement? Transfer case fluid change up to date?

[The Roadie]

Oh, I just spotted your post on trailvoy asking the same question. You might as well not bother. Sign up at GMTNation.com where all the trailvoy volunteers moved to six weeks ago. Trailvoy is a wasteland of clueless noobs answering noobs.

Here's the background:
http://gmtnation.com/f5/welcome-gmtnati ... story-226/

[Karo]

Hm same problems here, haven´t solved this problem so far.
Did you have a suspension lift in the front and maybe other springs?

KaRo

[s3customs]

4HI on pavement? Have you tried that before and felt driveline binding? Loose ball joint could give you vibration under torque application. How about with the 5% torque you get in A4WD mode on pavement? Transfer case fluid change up to date?

Was in 4hi on snow covered roads . havent tried awd or 4lo. diff oil could use a changing.

[DJones]

Edited original post for content.

[s3customs]

4HI on pavement? Have you tried that before and felt driveline binding? Loose ball joint could give you vibration under torque application. How about with the 5% torque you get in A4WD mode on pavement? Transfer case fluid change up to date?

At stop lights on my way home i switched back and forth between 4hi and a4wd and its still there in a4wd but not as bad . Probably the shake is at 50-60% of what it is in 4hi.

[Trail X]

What is your lift arrangement?

It could be the tripod joint binding up.

Lift your front end off the ground entirely by the frame. When in 2WD, spin the tires by hand and see if you feel any vibrations (or if you can spin them at all). Try it again in 4WD.

[s3customs]

What is your lift arrangement?

It could be the tripod joint binding up.

Lift your front end off the ground entirely by the frame. When in 2WD, spin the tires by hand and see if you feel any vibrations (or if you can spin them at all). Try it again in 4WD.

Thanks for the reply.. i have marks 3inch lift with 86 springs and Bilstein HD Struts and the my uper control arms are flipped. in the rear its marks 2 in spacer with z71 springs and bilstein shocks for a avalanche.

[DirtyBacon04]

What is your lift arrangement?

It could be the tripod joint binding up.

Lift your front end off the ground entirely by the frame. When in 2WD, spin the tires by hand and see if you feel any vibrations (or if you can spin them at all). Try it again in 4WD.

Oh damn, i was just thinking the same thing. I guess y'all are teaching me well.

[Trail X]

Lift your front end off the ground entirely by the frame. When in 2WD, spin the tires by hand and see if you feel any vibrations (or if you can spin them at all). Try it again in 4WD.

Thanks for the reply.. i have marks 3inch lift with 86 springs and Bilstein HD Struts and the my uper control arms are flipped. in the rear its marks 2 in spacer with z71 springs and bilstein shocks for a avalanche.

Ok, lift your front end entirely off the ground via the frame, and spin the tires, as I said. Report back your findings. Getting your hands on the wheels is sometimes the best way to locate a vibration.

[s3customs]

First chance i get i will try that. hoping its not that. NOt doubting you at all and appreciate the help but im hoping its the universal joint on the front drive shaft because i would think if it was the cvs i would feel the shake in the wheel but i feel it more in the floor

[Philberto]

I always get a noticeable vibration from the drivetrain when on pavement in 4hi, but not what I would call a "bad shake". I attribute it to that forward shaft being out of balance just enough that it's noticeable at high speeds. Then again, I'm always in 2hi on the roads, the exception being when there's super-heavy rain with potential for hydroplaning or massive traction loss due to my worn-ass tires.

[v7guy]

basically the guys want to make sure you're front diff and disconnect is ok. tie rod ends can also cause the problems you describe.

[Skindiggers]

Did a search and couldnt find a solution to this problem that others have also had. In 2wd everything is smooth and vibration free. in 4hi there was a bad shake. My first thought as bad as it was that it was a wheel loose. ( i think coming more from the right front ) when accelerating( not hammering on it just normal picking up speed, then goes away when i let up or am just cruising. Changed both cvs today thinking that was the issue ( right one was pretty bad. But to my disappointment the shake is still there, slightly better but still there. I did notice the lower ball joint on that side needs to be replaced, not sure if it would do this or not. Both wheel barrings , outer tie rods , struts and springs have all been replaced over the last six months so i have ruled them out. any help on this would be greatly appreciated

I have the same problem with my truck ! I have the same shocks (new) , the same lift ( new) , same springs , all the fluids changed 2 weeks ago . I thought it was from the cvs , or from the front drive shaft , the vibration is like when you lift the car too much and the drive shaft is in a bad angle ( when you drive normal you can not feel it but when you accelerate you will feel it) !
Mark sent me all 4 ball joints , i will receive them this week and i will change them and let you know , but i don't think , the vibration is from there .

[Skindiggers]

P.S.: Do you shave the sway bar mounted ??
I took it off 2 days ago and yesterday i was driving on a snowy road , ascending , when i noticed the vibrations !

[v7guy]

I don't have the front sway bar connected and notice no vibrations.

I do get a clank occasionally under sudden large suspension drops, but I assume that's the A arm hitting the disconnected swaybar.

[Skindiggers]

That "clank" is the shock absorber at full extension , i have it also..
Do you have OEM CV joints ?

[s3customs]

I havent had time to check it out. Luckily we have good weather and no need for 4 wheel drive. One side of my sway bar is missing the link. looking into getting longer ones but want stock style ends to avoid the noise from hiems joints. I do need to replace the passenger lower ball joint. its been sitting in my back seat for two weeks just been busy at my shop and havent had time to put it on. I did replace the cvs with the hd 6 rib units from o ryles couple weeks ago hoping that was the source of the shake.

[s3customs]

I jacked the front up so the wheels were off the ground and the suspension was at full droop and spun the tires by hand. Ididnt feel any binding and the tires spun freely. I did feel some play in the front drive shaft at the joint that is at the transfer case But not sure if it is normal. So what does that tell me and were do i go next?