need help with drive train troubles

[Happy Hummer]

04/29/14 (approximately)
This past week stopped by local shop and had a tech ride along to see what his thoughts were with this rotational noise in the front end of 07 H3 62k miles well maintained Hummer. Happy has AT tires 8k miles and rotated.

His observations were as follows:
* brake slides not allowing pads to retract (worked on these tonight. They are all cleaned up and back in place. They were very crusted in rust.)(on a side note if anyone has an extra clip to hold the slide pins I sure could use it please? )

* brake calipers ceased (brakes are equal depth and 1/4" of pad left easy)
* alignment
* hub (have now rechecked these...tight and quiet)
* tires (8k miles)

05/04/14..
Jacked up Happy just a few minutes ago and checked all of the wheels for rational movement.
Some observations:
1) with bar under front wheels checked for play couldn't find any
2) with transmission shifted into drive tires move at both back and passenger front
3) with Happy in 4 hi lock same 3 wheels spun
4) with Happy in 4 lo lock all 4 spin but drivers side seems slower than passengers
Note... I'm am guessing due to open differential?

More observations. ...:
1) when spinning back wheels free hand they rotate freely but have some drag and a squeaky kind almost like rusty door hinge sound on both sides.
2) the front passenger side has a lot of rusty door hinge sound wheel spin and not as easy to turn
3) drivers side rotates easier but same rusty hinge rotational sound.
4) everything is nice and snug/tight where it should be.

So some questions?
* I accidentally forgot to apply the brakes and got a grinding sound from transmission when shifting drive to reverse/park... will this hurt the drive train from this happening one time? was on the jacks at the time...

* I was nervous about increasing the speed any further than idle. ...
* when I drive I've been noticing a rotational sound and didn't put 2 & 2 together till hearing the noise today
* also noticed that my stability track little squiggly idiot light was flashing in 4 hi & lo lock when on the jacks. Does the abs cause this?

* when back on solid Terra the truck did not flash and all gears work fine without noise

So what to check or do next?
Am I looking at brake or abs issue?

Chris

 

[USMC_TOP]

Yes you have open differentials so if your sitting on Jack stands in drive the wheels may spin at a different rate. As for your issue, I guess I'm not fully understanding what your hearing. Maybe something caught between the rotor and the cover behind it?

 

[digglesworth]

You can buy new pins/clips for your calipers at AutoZone... It's a few dollars. Grease em up with brake grease and they'll be good and slippery.

 

[alrock]

* I accidentally forgot to apply the brakes and got a grinding sound from transmission when shifting drive to reverse/park... will this hurt the drive train from this happening one time? was on the jacks at the time...

* I was nervous about increasing the speed any further than idle. ...
* when I drive I've been noticing a rotational sound and didn't put 2 & 2 together till hearing the noise today
* also noticed that my stability track little squiggly idiot light was flashing in 4 hi & lo lock when on the jacks. Does the abs cause this?

Trans noise - parking pawl noise. Normal, not ideal, not what you want to repeat all of the time. You should be fine.
Stability track was on because you were on the jack stands and the tires were spinning at different speeds. Normal operation.

Seized calipers - did you address this? May be more than just rusty pins. If the pistons themselves are not retracting then your pads are staying against the rotors causing this issue. I didn't hear how you addressed the seized calipers.

 

[Happy Hummer]

I'm not certain if calipers are ceased? All the wheels spin freely when on the jack stands. Albeit less easily in front. The front slide pins were removed and cleaned of all rust and lightly greased last week. This seem to help slightly but not enough. Pads on inside of each front rotor are less material then outboard pad... is this a possible tattle?

Chris

 

[digglesworth]

If you pull the calipers off, make sure the rubber boots on the pistons are not torn or have any holes allowing moisture and contaminants into the pistons. Just little clues you can look for... Good luck. I hope you get it worked out.

 

[Happy Hummer]

Actually had a chance after business tonight to tear it down.
Took the calipers off. Pads. All the hardware. All the bolts for CV axles.
Inspected everything. I mean lol everything. There is nothing loose or sloppy in the front end.
Cleaned everthing. Removed all rust. Sanded and adjust brakes components.
Calipers are clean no tears in boots. The pistons do have a bit of rusty discoloration but no damage.
CV boots are in great shape. Front end checks out. Even retested front hubs, ball joints.

One thing of note:
While investigation went on I did find that I had some deep gouges in the inside of the calipers from the rotor which was encrusted in rust. Beat all the rust of the rotors and used a 3m double clean off wheel to restore the metal of the rotors to factory clean. Also removed all rust build up in caliper pad contact points.

There is no rusty hinge sound any longer. We there this will get the low rumble Mt type tire noise cleared up is anyone's best guess. I'm beat tonight so did not take a long ride.

Chris