Shimmy on the highway? CV Axles or U-Joints?

[Dustin Jackson]

I've had a bit of a slight shake between 30-60 MPH and I thought it was my tires. I got new tires and I still have the problem. I suspect that my passenger CV axle is the cause? I got under and pulled on the driveshaft and it felt tight so I don't know if it could be a U-Joint?

Entire front end is new except for the steering rack and CV axles.

Brand new motor and transmission mounts.

Sometimes it drives fine other times its unfortunate driving because of how nice of a rig it is from all the work I've put into it.

This is one of the last problems I am having with this Tahoe and I look forward to fixing it, any ideas would be great thanks guys

 

[Fless]

A tight CV axle might bind and cause vibration. Could you put the front end up on jackstands and spin the tires at different speeds, to see if either one makes noise or jerks a little?

I assume that the hubs have been done?

 

[Dustin Jackson]

A tight CV axle might bind and cause vibration. Could you put the front end up on jackstands and spin the tires at different speeds, to see if either one makes noise or jerks a little?

I assume that the hubs have been done?

@Fless Tight as in bad angles? I will try that and see what happens.

Hubs are new, I have a new CV axle that just came in the mail to replace my torn passenger axle.

I am thinking about just removing both the CV axles and driving it for a week to eliminate them from the equation entirely.

 

[wsteele]

A dragging brake puck can make a vibration that will feel like a slight shimmy. If you think that might be it, a simple way to check is to use a hand held infrared thermometer (or some other type of temp probe) and compare temps on the rotors side to side. The hotter side would be where to check.

 

[Dustin Jackson]

@wsteele Interesting, I assume my calipers are almost due to be replaced. They seem to grind a lot so maybe I just need new calipers and brake lines. I never thought it would have this affect tho, I will look into this.

 

[Fless]

@Fless Tight as in bad angles? I will try that and see what happens.

Hubs are new, I have a new CV axle that just came in the mail to replace my torn passenger axle.

I am thinking about just removing both the CV axles and driving it for a week to eliminate them from the equation entirely.

Tight as in not smooth and not easily moving.

Some (many?) hubs require the CV axles to be installed so they don't come apart under load, so I'm not sure I'd drive it without the axles installed. I believe there is a roll-formed hub that doesn't come apart, but I have no firsthand experience with that.

 

[Dustin Jackson]

Tight as in not smooth and easily moving.

Some (many?) hubs require the CV axles to be installed so they don't come apart under load, so I'm not sure I'd drive it without the axles installed. I believe there is a roll-formed hub that doesn't come apart, but I have no firsthand experience with that.

@Fless I am running premium MOOG roll-formed HUBs so I should be ok

 

[swathdiver]

I've had a bit of a slight shake between 30-60 MPH and I thought it was my tires. I got new tires and I still have the problem. I suspect that my passenger CV axle is the cause? I got under and pulled on the driveshaft and it felt tight so I don't know if it could be a U-Joint?

Entire front end is new except for the steering rack and CV axles.

Brand new motor and transmission mounts.

Sometimes it drives fine other times its unfortunate driving because of how nice of a rig it is from all the work I've put into it.

This is one of the last problems I am having with this Tahoe and I look forward to fixing it, any ideas would be great thanks guys

A rhythmic vibration is almost always the tires, don't rule out the new ones just yet. Definitely do not run without the half shafts in your truck with stock hubs. A woman was killed recently when a hub separated from a truck and crashed into the cab of her GMC, killing her.

Lesser culprits are u-joints and other driveline components. Are the slides on the calipers clean and greased? The pins still working good, caliper pistons not sticking?

 

[Dustin Jackson]

@swathdiver I think it would be rare that the old tires and the new tires had the same problem. Not running stock HUBs so I am good there. I wonder if it could be a sticking caliper?

Its hard to describe but its more of a wiggle when going down the road.

 

[swathdiver]

@swathdiver I think it would be rare that the old tires and the new tires had the same problem. Not running stock HUBs so I am good there. I wonder if it could be a sticking caliper?

Its hard to describe but its more of a wiggle when going down the road.

Ok, that's different. End links, sway bar bushings, proper torque specs on all pieces. Inner and outer tie rods, no more than half a millimeter of play in either.

The first time a piston on a front caliper hung up, there was a slight shimmy on the way out and then it started pulling the wheel over on the way home. Several months later it just locked up.

We see a lot of repeat trips to the tire stores to cure vibrations because the techs don't care or don't know what they 're doing. I hope someday to get a shop building again and have my own machines so that I know it's done right the first time and all of my children and their families can benefit too.

Curious, what hubs are you running that allow the half shafts to be removed?