steering vibe

I have a mild to moderate vibration in my steering wheel. Closer to "mild", I'd say. I have read quite a few threads on steering vibes, U-joints, carrier/center bearing replacement, and the tack-weld fix. None seem to hit my problem precisely. Facts/data:

-2001 4WD 4-door SR5, non-TRD, 6 cylinder, automatic transmission, 120K miles, never taken off-road, never wrecked. I am the sole owner.

-No significant mods to the truck. Not lifted. Original front- and rear-end components are all still installed, except:
-I recently replaced the shock absorbers and struts with "OEM Spectrum" from Rock Auto.
-I recently replaced the steering rack bushings with Energy Suspension brand.

-Tires are stock size, on OEM rims. They are a low end brand--Nexen Roadian--with 15K miles on them. They were rotated and balanced one week ago by the selling shop.

--The right front rim has a 3/8" crack radiating from one lug hole. I just noticed it yesterday; no idea how long it's been there.

-The vibration is present at all speeds (from 10 MPH up to 70 MPH, anyway). Vibration is absent in Neutral and Park. It seems to be present on both smooth and rough roads; I would say it's a bit more noticeable on rough roads, but not much. The vibe is not impacted by braking.

-My center bearing has very little play.

My mechanic is thinking U-joints, and wants to do a test drive. Any help or thoughts appreciated.

Zach

 

A shop sold you tires, mounted and balanced them, and never noticed or told you that one of the wheels was cracked? That's downright shady, and calls into question their ability to properly mount/balance those tires. That would be the first thing I'd check. Also, buy a new wheel.

In general, vibrations due to faulty/worn out U-joints are speed sensitive, so if you're feeling the same vibration intensity regardless of speed, there's a good chance it's not a U-joint. If you lube both driveshafts properly and the vibrations go away, you can reexamine the U-joints as a culprit.

 

Thanks, DRR. Perhaps I should install the spare tire on the right front, and take a spin and see if the vibration goes away. ??

 

Couldn't hurt, although I'm doubtful that that's the only cause of vibration, if at all. When you replaced the steering rack bushings, did you check for play in the rack guide? If you jack up the front of your truck, try wiggling the front tires back and forth by hand to see if there is any slop. There should be no movement in the tie rod ends.

Just to be certain, when you go on your test drive, try shifting into 4hi whenever you feel the vibrations are the strongest (below 55 mph). If the vibrations completely go away when you're in 4hi, it could be a problem with the needle bearings in the front differential. It doesn't sound like that's the problem, but you might as well check. How long have you had these vibes?

 

While you're rolling at highway speed and you put it in neutral, is the vibration still there?

Is the vibration relative to ground speed or engine speed? Does it change with RPMs? Unaffected?

Was it present before the last tire rotation?

 

BW:
The vibration has been with me at least nine months, as it was the reason for my last two R & B's, in May of last year and about two weeks ago. May '14 was also when I did the steering rack bushings, as the second thing to try and make it go away. So, I reckon I've been chasing it for a year or more.

I will try the shift-to-neutral at speed test.

 

DRR:
I will lift the front end when I get a chance. I was originally thinking "tie rod ends" to myself. As to play in the rack guide, I may need clarification on what part hat is. ?? (Keep in mind, I am a serious amateur...)

On your fourth gear test, I don't think I can do that, as it's an automatic.

Vibrations became noticeable about one year ago.

 

The steering rack guide is the big female hex bolt in this picture. If you pull it out you'll see the guide which holds the rack in place - I'm not an expert on these but there are plenty of good threads on checking/rebuilding these steering racks.

As for the road test, what I meant was put it in 4x4 while you're driving, not 4th gear. Engaging the front differential will stop any vibrations associated with the needle bearings in the diff, and you'll notice the difference right away if that's the case.

 

I may need glasses, LOL. I now see you wrote '4hi' vice '4th'. I tried what you describe this afternoon at about 35-40 MPH. I don't think I felt any change; I will try it again.

As to the rack guide--I hate being dense--do you mean the silver piece within the yellow circle? Or the large female plug to the right? I will research the threads harder.

I also, I ordered a nice-looking wheel off eBay earlier today.