GM Truck Club Forum banner

Silverado intermittent vibration

17K views 17 replies 11 participants last post by  Bubbanbrenda  
#1 ·
I've got a 2012 Silverado. 5.3 1500 z71 4x4, active fuel management delete, cab and a half, short bed, and factory suspension and exhaust if it matters. I bought it used at 130k miles so I don't know it's full history, just that it's a rebuilt title. I've got an intermittent vibration, almost constantly. Let me explain. When I bought the truck I noticed it at a specific rpm range/speed. It was 35-65 mph and 1300-2k rpms under a load. It would vibrate for 2 or 3 seconds and stop for 2 or 3 seconds and repeat but went away when accelerating faster than 2k rpms until engine speed comes back down. Not gear dependant. Fast forward to 140k now it's noticed at all speed ranged up to 70. And recently I felt it up to 2300 rpms so it's getting worse. I've also noticed that at lower speeds (up to 45ish) that the tach will respond with the vibration. Up 100 rpms or so then back down when vibration stops again. The dash and computer only show traction control fault from bad steering angle sensor so traction control and stabilitrac lights are on, no other trouble codes active or otherwise when scanned. The truck preforms everything great. Plenty of power, 4x high and low, acceleration, and braking, towing, ect. Since I've owned the truck I've replaced tires around the entire truck, all mounted and balanced with full alignment at a shop, all brake hardware(pads, rotors, drums, springs, wheel cylinders, rear shoes, brake fluid, ect. Oil changes in transfer case, engine (x2), and rear end, replaced all spark plugs and coil wires with Delco parts, replaced the entire rear end assembly, and rear shaft u joints, front and rear. I'm a career boat mechanic but this vibration has myself and all my mechanic friends (marine and semi truck) stumped. The shop that did the tires and alignment let me know the front end components need replaced. Inner and outer tie rod ends, upper and lower controls arms, and ball joints. But vibration comes (and goes) from the bottom of the truck, not steering wheel. Also truck rides smooth as porcelain when you pull your foot from the throttle pedal at any speed. Cruising at 60, on and off vibration with cruise control or throttle. Break cruise control or release pressure off throttle pedal and vibration completely goes away. And the most mysterious symptom is after 30-40 minutes of straight highway speed (50-70+) the vibration goes away entirely and is only felt every 20 minutes or so. Ideas?!?
 
#6 ·
Long prybar, a flashlight, and a friend.

If your motor dances when you start it or give it gas, then you can skip the inspection. You need motor mounts.

Look for cracking, separation, uneven deformation, incomplete bearing on the thru bolts (if present). They'll generally look screwed up, if they are.

I would examine your front U-joints, CV axles, etc. for slop or wear. They may be coming apart and not show it. Last set of U-joints I did appeared solid until I pulled them out.
 
#8 ·
Rebuilt title could be a problem. Probably a wrecked truck insurance totalled where cost to repair was more than truck value
Owner bought it back or auctioned off and somebody bought it and repaired and applied for a rebuilt title.
Try to get a history report and find out why it was totalled. Might give you some clues on driveline and suspension issues.
Good luck.
 
  • Like
Reactions: RayVoy
#14 ·
the axle u joints vibrations ! my Silverado updated it the u joints .
the front axle bearing hub my Silverado new Timken bearings ....
the u joints rear axle , and the front axle bearings the grease ..
so the axle diff/transfer converter / transmission 40K-50K miles various new fluids ...
the dex fluids III no >>>>..... 1999 mobil syn transmission fluids very great ... 1996 Impala / 2000 Silverado no damaged it !!!!!!