Diesel Place banner

1 - 20 of 57 Posts

·
Registered
Joined
·
320 Posts
Discussion Starter #1
I have this horrible vibration coming from under the truck when in 4 wd. It's right under my feet and I can hear it over the radio at moderate volumes. When I take my foot off the gas it goes away but as soon as I attempt to accelerate at any amount it comes back. As soon as 4wd disengages it goes away. Any ideas what this could be?
 

·
Registered
Joined
·
345 Posts
My truck has a slight vibration in 4wd under acceleation too. As far as i've herd its just normal. Anyone else have an idea?
 

·
Registered
Joined
·
16,971 Posts
Are you talking about 4HI or 4LO? I have a slight vibration in 4HI but not the other. Have you had someone drive the truck while you stood off to the side to "see" what you can "hear", might help determine what is going on. Dealer said mine was normal...
 

·
Registered
Joined
·
5,495 Posts
I never had any vibration in mine in 4wd untill the transfer case was shot.
 

·
Registered
Joined
·
320 Posts
Discussion Starter #5
I have never put it in 4wdl before.. this is only 4wd high. I'm going to make an appointment to have it looked at within the next few weeks.
 

·
Registered
Joined
·
320 Posts
Discussion Starter #6
Ok, I was playing around a little bit yesterday in different speeds and noticed that I can't get it to vibrate under 50mph. As soon as it hits the 50-53mph range is when it kicks in and my foot vibrates if I have it on the floor of the truck.. as soon as I let off the gas it goes away.. again this vibration sound is louder then the engine of the truck... Not much but while it vibrates I can't hear the engine until I let off or back down and stay one speed.
 

·
Registered
Joined
·
264 Posts
Maybe your CV angles are too steep to be going at high rate of speed.
 

·
Registered
Joined
·
382 Posts
Isn't that a sign of too big of a difference in front & rear axle angles? Then again your sig doesn't mention a lift and it doesn't look like you have one in your pic:confused:

I'd check your CVs and u-joints for play & wear.
 

·
Registered
Joined
·
426 Posts
I have the same issue but mines seems to pull left and right when it does so im clueless too
 

·
Registered
Joined
·
345 Posts
could leveling keys in the front even if it was aligned have something to do with it?
 

·
Registered
Joined
·
142 Posts
I'm Taking A Wild Guess Here....

Have you crawled under the truck and inspected the front drive shaft? You can turn it by hand. If by chance, and I know this is a remote possibility, you had something adhering to the shaft, like a glob of tar, mud or whatever, it could cause an out of balance situation. The driveshaft may just not have been balanced properly from the factory...You say you noticed it the first time you used 4X4???

That shaft being out of balance is my guess....

Also, if the shaft is out of balance, you should also get the vibration in 4 lo at certain speeds as well, although the speeds won't necessarily mimic 4 hi....

Good luck


Mike
 

·
Registered
Joined
·
565 Posts
This sounds like my problem too ... HELP

New truck, havent used 4wd until yesterday. Snow packed roads and I engaged 4wd at a slow rolling speed. Under acceleration everything sounds and operates what I would consider normal. During acceleration and deceleration there is normal noise, however, right between accel and decel where there is a point of "no load" I have a very noisey growl. It sounds like I'm driving on the rumble strips along the side of the freeway. This is not a normal sound, almost a dry metal sound or a dry bearing noise.

As soon as I accelerate any tiny bit, the sound goes away (under torque). If I decelerate (slowing under torque), no noise. Its that in-between where things are at "no load" that this noise is present.

Havent used 4wd til now so cant say if it ever did this before. I dont know if its transfer case or front diff. Its quiet in 2wd.

*EDIT*

It seems to only make this noise in 4H and over 30 mph. I ran it in 4L over 30 mph and no noise so it must be high range specific. Would this indicate transfer case?
 

·
Registered
Joined
·
1,371 Posts
This is suppoesedly normal. My truck has it, bobo's truck has it...I have a lift, he doesn't!

It bothers me too, but I can't figured out where the vibration is coming from specifically.
 

·
Registered
Joined
·
435 Posts
My truck does this too. COuld it be a bad wheel bearing... or would it make the noise in 2wheel also?
 

·
Registered
Joined
·
565 Posts
Could it be this?

Well I crawled under my truck today and started looking for anything obvious like a loose u-joint or any excess shaft movement.

The only thing I found that raised an eye-brow was movement in the output shaft at the transfer case. I laid underneath and could move the output shaft ever so slightly up/down and side to side. There wasnt alot of movement but more than I would expect. All other shafts were solid ... input shaft on the front diff was solid, no movement and both CV's were solid, no movement.

I would think that the output shaft bearing on the transfer case would not allow any side to side movement, especially by hand. I can see where this could be where my noise is coming from.

Anyone else want to check theirs for movement and tell me if this is normal? I would greatly appreciate an effort to check other trucks to see if this is a normal condition or something I need to worry about.

Thanks for any help.
 

·
Registered
Joined
·
126 Posts
My 03 is in the shop for this exact problem and as you described at 30 or above good god it sounds horrible and u can feel and hear it. So far they have split my transfer case replaced 2 bearings, pulled and split the front diff to no avail. Tomorrow the engineers are going to look at it. Truck never did it before and it has 47k on it. I personally think it's a bad transfer case but since it's warranty I have to let big brother do the work. Once they figure it out I will let you know...My noise started as a growl and now it sounds like chain kinda going over something. It's loud enough that you can hear it over the motor during decel and outside the truck as a i pass ya....pretty sad if u ask me :(

Pit
 

·
Registered
Joined
·
5,117 Posts
Great thread, I was coming back form Salt Lake on Sunday and had to lock it into 4hi for about 30 miles and I had the same sound. It was a little bit disturbing, as I was seeing two wheel drive vehicles smashing agaist the barrier rail right and left. I was thinking this would not be the place to lose four wheel drive. Mine only does it under moderate acceleration and let off, and starts at about 45 mph. My truck has the floor shifter so the noise probably sounds a little bit louder due to the hole in the floor. I didn't have any problems with operation though, so I hope it is alright.
 

·
Registered
Joined
·
49 Posts
I have the same problem with my truck. 03 chev duramax. Took it to the dealer. They changed the front diff, $2800 later the noise is still there, now they say the noise is normal.
 

·
Registered
Joined
·
565 Posts
Chassis Ear

My truck goes into the dealer tomorrow. We are going to hook up a chassis ear to several locations under the truck then go out and duplicate the noise. We should be able to find where the noise is coming from .. ie: differential, transfer case .. etc. I will post our findings after.
 
1 - 20 of 57 Posts
Top