HawkZ28

Long-time lurker, first time poster. I have a 2010 Sierra CC 4x4 that has a vibration that had gotten worse over time. I noticed it primarily at highway speeds of 75mph plus, but it's became noticeable at lower speeds as low as 55 as of late.

What has me stumped is it gets even worse if I'm going 75, and kick it into nuetral. It's also became noticeable while crossing and climbing hills. U joints are new in the last 10k. Tires are 275/60 20 Goodyear Wranglers, about 1/2 tread on aftermarket wheels. Any ideas on what to check or causes?

Thank you in advance!

FFDP

iTrader: (2)

Do the wheels center on the hub?

Like they do not require hub centric rings.

Can you see if any of the driveshaft weights have broken off? I know it may be hard to tell but it's worth a look.

HawkZ28

I'll have to check. Last time I rotated tires I saw they have hub spacers/center rings, which I kept on each wheel. I'll double check them for center and lug torque.

I have a vague memory of how many weights were where from doing the u joints and the rear diff and x case fluids. I'll check if there's anything that looks missing.

Only other thing I can think of is out of balance tires or a slipped belt on a tire?

HawkZ28

So got the truck in the air tonight, and found a bad upper bj on the passenger side and the CV joint in knew about, and a bad lower bj on the driver's. Jacked up the rear and couldn't find anything out of the ordinary other than a light rub on the driver's drum. Brother in law stopped by, and we lifted the rear end and found the driveshaft wobbling while idling in gear, rear supported off ground. Turns out Advance Auto doesn't know what u joints are supposed to go in my truck, and sold me 2 wrong joints for the truck- 232a and 331a were the wrong size.

We also found a lot of play in the tranny mount, so I'll be doing that as well, and found out my tcase encoder motor is stuck and not disengaging the front driveshaft since it was spinning the entire time too. I've got my weekend planned....

madmann26

iTrader: (7)

Have your driveshaft balanced when you get the right joints in.

HawkZ28

My brother in law is taking it with him to his guy in Omaha for that. I thought he said they balance it to some insane rpm like 9 or 10k.