odd noise from dash when back wheels spin free.

[Scottydoggs]

hi all, hoping someone has heard this sound before. i just got this 05 tahoe a few days back, it just snowed here so i went out to "play" and test things out, rpo's say its got a locker mainly wanted to make sure it works.

so if im moving, or from a stop if i spin the tires i hear this zipping sound from what seems like the behind the dash.

im thinking of jacking the back wheels in the air then putting it in gear to see if o can make it happen like that to pin point the sound better.

heres a vid of this noise cause its nothing ive ever heard before. truck has no dummy lights on at all. tc button works.

oh, t/c, this is with t/c off. but if it's left on it still makes the same sounds and does spin the tires.

it does it the first time, not the second, and then does it real loud the third time. other then this i see no other possible issues.

thanks scott.

 

[TwiztidPixel]

You have an exhaust leak somewhere. Manifold, flex pipe or gasket.

 

[PG01]

Is your dog in there with you? Sounds like a dog throwing up...

 

[1_8TTony]

Ruptured brake booster diaphram??????

Just a guess.

 

[Doubeleive]

pull the dash trim off and the bottom cover and if necessary the cluster and keep doing it till you pin point it, after listening to it sounds like it could be brake related, are you getting any pulsing/pulsating out of the brake pedal when it happens?

 

[Scottydoggs]

it does feel odd when i hit the brake to stop the wheels when i had it on a jack to repeat it.

i just bought the truck a few weeks back, after its first hwy drive coming off the hwy it started to pulse the brakes, feels like warped rotors or maybe lot rot on the rotors.

booster would be worth looking into, only i have hydro boost brakes.

ordered new brakes all around, R1 e lines and they are finally getting installed tomorrow. had em for days now. but work was in the way as always. hope that smooths them out.

made another post in engine section, has a second vid on a jack. http://www.tahoeyukonforum.com/threads/odd-sounds-behind-dash.99204/

 

[Doubeleive]

is the abs light on? even if is not any pulsating feeling could also (possibly) be from the abs system which runs off of a main unit that gets information from the wheel hubs, if there is bad hub or bad wheel sensor it can cause a pulsing but it is usually pretty apparent when coming to a normal full stop at the very end of the stop you would get a pulse and/or jerky stop and the abs light would normally be on or would come on then go back off again when you shut off and restarted. you can check the front wheel hubs for play by simply jacking it up and seeing if there is any play when you try to move the wheel 6-to-12, a little play at 3-to-9 is normal as the wheels will move with steering, a lot of play at 3-to-9 would be tie rods or linkages, but 6-to-12 should have no play.

 

[Scottydoggs]

not a single dummy light is on. stops smooth until the brakes get some heat in them. then they pulse, goes away when you let off the brakes of course.

its definitely not abs pulse as far as i can tell. i know what that feels like.

ill check the hubs for play when i do the brakes. ive warped rotors before, it feels just like that.

i can also hit the local garage here, guy has let me use his snap on scanner for free in the past for abs codes on my regal. be worth a look for whats in history.

main issue is wtf is the damn zipping sound when they spin free. never heard that one before.

it kinda reminds me of a abs sound when its active and your braking hard in snow with the pedal hitting the floor like a mush pile.

 

[Doubeleive]

ya that's what it kind of sounds like

 

[Matahoe]

Noise could be the auxiliary brake booster pump engaging. I know it makes noise at low rpm when there is a traction control event that limits wheel rotation so you don't fishtail all over the place. I tried to do the exact wheel spin on an icy driveway yesterday and I got pretty much the same effect as you did.

 

[Scottydoggs]

you have hydro boost brake booster? and you got that same zipping sound?

 

[Matahoe]

Right. If you do have hydro boost the vehicle will have an auxiliary brake boost pump. It makes a distinctive "woosh" noise emanating from behind the dash area. The pump is tested the first time you reach 10 mph after startup. If it's the same noise as that then you found the answer.

 

[Scottydoggs]

ok, so its normal and nothing going bad then? all my p/u trucks had hydro boost too, i used to plow in 2wd all the time up to 6 inches, cause i could. wheels spun all the time, never heard any of that before. but this hoe is newer by 2 years and has more crap going on for sure.

now that clang when it hits the steering locks.........that cant be normal lol

 

[Matahoe]

ok, so its normal and nothing going bad then?

To be certain you can always disconnect the auxillary boost pump electrical connector and see if the noise continues after testing the same way.

 

[Scottydoggs]

i got two threads for the same thing, heres the new lock to lock sound. its also in the dash same sound left or right

 

[Scottydoggs]

is that under the dash? its been to cold here to really dive in and rip it open.

 

[Matahoe]

i got two threads for the same thing, heres the new lock to lock sound.

Sounds like a loose steering component. Can you replicate the sound with the engine off and yanking the steering wheel back and forth? If so then it's a column issue. If not then the loose component is in the steering linkage down below after the steering gear. A clanking sound like that could be a bad idler or pitman arm ball joint. But you need to get up under there and see while someone turns the wheel for you.

How many miles you got on that truck? Any truck over 8 years old will probably need new everything replaced in the steering linkage due to age. At the very least get the whole steering system inspected for looseness and proper operation.

 

[Scottydoggs]

ill give it a shot engine off. see what i come up with.

i was thinking maybe the lower column bearing went bad, seen a vid on that, they showed how to tell if its bad by just grabbing and giving the shaft a wiggle at the base of the column.

 

[Scottydoggs]

shes got 120 on it, one owner. front end feels tight still been at it doing all the pull push tests. ive been wrenching on my own crap for 30+ years now, so im not a noob at most stuff. replaced the 03 gmc hd's front end parts 3 times, i know when that stuff's dead lol

these are all new noises ive never heard before. figured some of this has to be a common failure and been dealt with before.

 

[Matahoe]

If its making a clunk noise then the intermediate shaft is something that needs to be replaced. Usually seems like clockwork every 30-50k. If it's never been done then add that to your list.

Pray it isn't the lower column bearing. You have to remove the entire column and replace the steering position sensor for that. Not fun.