ss4chad

iTrader: (19)

So at 100 the truck has a vibration, I have verified pinion angle, got new Drive Shaft, new rear end guts and axles and a new trans. Vibration still there. Truck is an '03 Sierra, 8ft bed, lowered 3/4 with 20x10 in the rear on 295/40 20 tires. New Rear Shocks and Verified the frame is straight by local Frame Shop.

Vibrates on the road and the Dyno.

Could it be caused by weak or wore out leaf springs? Or do I need to keep playing with the Pinion Angle?

Chad

wretched73

iTrader: (1)

Looks like you tried everything but the wheels and tires. I would have started there. Verify they're properly balanced to handle 100+ mph speeds. Verify they aren't bent or tweaked in any way

ss4chad

iTrader: (19)

Thanks man, I had 18" on the truck before and it vibrated as well. It had Continental Extreme Contact DWS06 with a 'Y' Speed rating of 186.

I am running the same tire brand and model in the 20" tires Extreme Contact DWS06 with a 'W' speed rating of 168. Computer balanced from Discount Tire.

Chad

wretched73

iTrader: (1)

I'm not sure how they balance them there. Maybe look into high speed balancing?

Since you say it shakes on the dyno too, I assume its only the rear that is having an issue. If so, make sure your rear is square. Maybe even rotate the tires to see if you can pinpoint the problem and see if its only with one wheel?

madmann26

iTrader: (7)

"Computer balanced" or Road Force balance.

Vastly different.

Warped rotors? Drums out of round? Anything that moves while driving is subject to cause a vibration.

Northeastconfederate

I've experienced warped rotors and a sticky caliper causing a rear shimmy that I swore was a tire issue. Had just gotten new tires and the shop ended up getting me 4 new tires from his distributor. Didn't fix it. Replaced sticky caliper and machined the rotors and it improved. This shocked me; I was a Benz tech for 17 years and never had a rotor or brake issue cause a shimmy unless it was under braking.

ss4chad

iTrader: (19)

Replaced the factory rotors with cross drilled slotted rotors. New Wagoner pads as well.

I also replaced the rear end with an Eaton Posi track, new richmond gears and a one new axle. Made sure everything is aligned and shimmed properly.

Chad