Noise on deceleration

[cruisermaine]

I need some help identifying a noise my truck has started making. It is most noticible from the right side when coasting down at lower speeds. It is a metallic ticking sound -almost like a playing card in bicycle spokes (remember that). The speed of the "ticking" sound varies proportionately with vehicle speed. It doesn't seem to mke the noise when under throttle -not sure if this is just because I can't hear it over the engine /wind noise. for background, my truck is a 95 with 146,000 and does not have lockers. I recently had all four brake rotors/ pads replaced and new front calipers installed at a local shop. I've looked under the truck to check for foreign objects I might have picked up on the trail but it is clean under there. I'm getting nervous about this....could it be gear noise from diffs or Xfer case? Any help greatly appreciated.

TIA

 

[landtank]

rock/screw/nail in the tire or possibly a Birf or wheel bearing. Have you had the axle done yet?

 

[cruisermaine]

rock/screw/nail in the tire or possibly a Birf or wheel bearing. Have you had the axle done yet?

Definitely not anything in the tire. My Birfs are in need -and the right one does click under heavy loads (not typically though), but this sounds very different and makes noise under no loading (coasting down on smooth road).

 

[Scamper]

Not sure it would make a metallic ticking sound--I would not have described it that way anyhow--but a long time ago, after working on the DS wheel, I inadvertently dislodged some of the clips that hold the rubber "skirt" in the wheel well. Just a couple of them were loose. When I got to a certain speed, I could hear it making a rythmic sound like a flapping or smacking sound that was very consistent and was proportional to speed (due to wind factors I'm sure).

Anyhoo, put the clips back on at a truck stop and the noise went away. Might as well check it out since it only takes 10 seconds and costs nothing to fix if that's it.

 

[Beowulf]

Peter,

Pull the ABS sensors, inspect, and clean the shavings from the magnetic sensor on the end. One 12mm bolt per side. They're plastic so be careful removing.

-B-

 

[cruisermaine]

I will take a look at them tonight and post back afterwards. Thanks.

 

[raoul reese]

noise

I had a very similar sound that I described with exactly the same words you used on my FJ40. It was the transfer case.

 

[cruisermaine]

I had a very similar sound that I described with exactly the same words you used on my FJ40. It was the transfer case.

ARGH, I sure hope not.... would that mean I need a new transfer case or just a part /bearing within? How much is a used or rebuilt case? I remember a recent post listed $2K for a new one.

 

[cruiserdan]

Toyota does not offer remaufactured transfercases. You can obtain replacement parts or a new case.

 

[IdahoDoug]

Peter,

I'll respectfully disagree with Beo - don't mess with the ABS sensors. No way you'd hear something hitting them from inside the birf. Something hitting them that hard would make noise once and the sensor would be in tiny chunks. Messing with the ABS sensor can, however, reward you with a cracked wire or other. Leave those pricy babes alone.

If I were you, I'd immediately check the brake calipers and rotors by removing the wheels. I don't know your level of mechanical aptitude, but I wouldn't drive it without checking the work since it involved the brakes.

If nothing, I would then suggest a wildly dangerous way to hear it which I'll detail later. After you've indemnified me in writing, of course.

DougM

 

[Beowulf]

>> I'll respectfully disagree with Beo <<

That's OK 'cause the suggestion for pulling the ABS sensor accomplishes all of your checks by having him pull the wheel and inspecting the rotor. If there is something caught that is causing the rythmic clicking then it is likely hitting the outter edge of the rotor (he says it varies with speed and sounds like a card in a bike spoke.) That implies it is not hitting the rotor surface. The other possibility is that the magnet on the ABS sensor has detached and is somehow hitting the ABS ring as those notches pass under the sensor. As for hearing that inside the birf.... you're correct, I certainly couldn't hear something like that but my *wife* could.

-B-

 

[Beowulf]

>> then suggest a wildly dangerous way to hear it which I'll detail later. <<

I saw a post in another forum with an ingenious method of listening for under chasis noises. The guy picked up 2 of the cheapie FRS radios with noise activated transmission. He put them on the same channel and rigged up one by attaching it under the truck wherever he wanted to listen to a noise and that was the transmitter. He said it worked perfectly. He also experimented with one of those cheap PC "boon" mikes with good results.

-B-

 

[IdahoDoug]

Mine involves far less money, way more risk, and your insurance company will laugh if you call for coverage/claims.

DougM

 

[cruisermaine]

OK, I pulled both front wheels and noticed something interesting (I had noted my brake rotors/pads/calipers had been replaced in front) on the right side the shop had apparently not bothered to tighten the six bolts holding the rotor and the hub together. several of the bolt heads weren't even close to being seated against the hub. I did not mess with the ABS sensors because I don't think the noise can be coming from inside the hub because it is too loud. Other than the loose bolts, I could not find anything that seemed to be causing the noise.

After putting wheels back on I drove the truck and the noise is still there. with the help of my wife was able to localize the noise to the rear half of the vehicle. I have read the recent thread on driveshaft issues and am wondering if it is possible for bad U-joints or other drive shaft issues could be making this noise. The noise is present in gear or in neutral, in hi and low range. I described it as a metallic ticking sound like a card in a spoked wheel In hindsight this was not the best description. The sound is more like the sound of a lug wrench being tapped against a brake rotor or driveshaft. While under the truck I noticed some play in the rear driveshaft. I can rotate it by hand about 1/8 inch or more and I can move it laterally about the same parallel to the yokes (sliding along the spider leg) as if the spider bearings are worn? As the shaft is on the right hand side of the truck I'm thinking this is the source of my noise. What do the resident experts think?
Oh, and thanks to the forum, I just found out that my front driveshaft is IN-phase - the PO must have had work done and....

 

[Rich]

Bad u joints can make knocking noises.