Mechanics

BRAKING VIBRATION

2007 GMC Sierra • 43,000 miles

I have a 2007 Gmc Sierra SLE ext cab 2wd. Today, I replaced the stock 17" rims and tires for a new set of 20" rims and tire (305/20/50) Truck rides and drives like a dream except when braking above 40 mph. Truck feels like its falling apart and mechanic said I had warped rotors.I believed him. Replaced both front rotors and pads and still did not help! Now when I stop I can feel more of the vibration towards the rear. No bent rims and tires were checked for balance twice today alone! Brake petal vibrates and truck feels like it coming apart when braking! Truck only has 43, 000 original miles and is well taken care of. No dash warning lights are coming on. What could be causing this? Scary.
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Sierra68
April 13, 2013.



When you alter the suspension with those huge rims, did you use spacers? Most likely the rims and tires are the cause of this issue.

What did you torque the wheels to? They must be hand torqued

Roy


ASEMaster6371
Apr 13, 2013.
Yes. Torqued to 140 ft/lbs.I think I got my answer from a Gm Tech. He said to remove retaining clips outter brake drum lug studs from factory. Stock GM wheels are cut to allow for these"clips". Aftermarket wheels do not and when you brake. It allows wheel to wobble and shake violently. Over 18 people had this same problem and all 18 it resolved the issue(fingers crossed)gonna pull them tomorrow and should have two per rear brake drum. Thanks!


Tiny
Sierra68
Apr 13, 2013.
100% that's what it was! Truck is now perfect! Remove those two clips that hold rear brake drums on from the factory! Who wouldve thought!


Tiny
Sierra68
Apr 15, 2013.


Tiny
Sierra68
Apr 15, 2013.