new tires - now getting a pulsing vibration on freeway (1 Viewer)

[riffman12]

I recently had 285/75/16 Falken Wildpeak AT3Ws mounted on my '97

At about 65+ mph I'm getting a strange vibration. It happens about every second. Like a low hum that pulses. hummmm...hummmmm...hummm

nowhere near as quickly as a tire or driveshaft spinning at 65mph.

I'm not feeling it through the steering wheel, more like a dull vibration through the whole chassis.

I tightened my front wheel bearings about 2 weeks ago and it never vibrated like this before the tires.

Has anyone experienced this? Is it possibly a tire balance issue even though the pulsing is so slow? Or could it be something else that is just now more noticeable that I have more rotating mass?

 

[sbman]

That really sounds like a u-joint issue to me. It's 'phasing' in and out? Probably your new tires are running smoother than what you had before and now you can notice the vibration that's been there for a while. Pull the driveshaft off and see if the u-joints have smooth movement at both ends. Checking it with the driveshaft on the truck doesn't work well.

 

[riffman12]

That really sounds like a u-joint issue to me. It's 'phasing' in and out? Probably your new tires are running smoother than what you had before and now you can notice the vibration that's been there for a while. Pull the driveshaft off and see if the u-joints have smooth movement at both ends. Checking it with the driveshaft on the truck doesn't work well.

yep phasing in and out is a good way to describe it. Is that usually a symptom of a bad u joint?

Is that something that just need lubing? Or likely to need a new joint?

 

[ElJayBird]

I seem to have always had this issue when running oversized tires across all of the vehicles I've owned. I've always assumed that it was normal. It's a low WahWahWahWahWahWah hum. No steering wobble or shake, which would indicate bad tire balance or off-center tire mounting...just a low pulsing hum.

 

[BILT4ME]

It can be the tire noise and the frequency since you're sitting between the sets of tires, it sets up a frequency modulation that seems to move in and out.

Common on lugged tires.

Although, I like the thought about the driveshaft vibration noise as well, however, new tires do not "change" the driveshaft relationships.

 

[sbman]

I have 285 75/16 Duratracs on my 97 LC. I had a very similar vibration and found a ujoint that was very worn out. Replacing it ended the vibration. Tires don't change any relationships of driveshafts but if the old ones were noisy or worn that can hide stuff you don't notice until the tires are running smooth. Or it could be just the tires making vibrations.

 

[ARB777]

I just got the at3ws 285/75 16. I had it roadforce balanced and never had any issue for about 3 weeks now. On the other hand i have a new set of ko2s on my other cruiser, balanced but not roadforce. I get vibrations at above 70 mph. I will get the ko2s roadforce balanced soon. We'll see if it fixes it.

 

[riffman12]

thanks guys I'll see if I can take a closer look at my U joints.

It feels more like a tire issue to me, I just wasn't sure if tire vibration would be more of a constant hum instead of this sort of pulsing.

It almost feels like there is some sort of weird resonance happening from the tires.

There is absolutely zero sign of vibration below 65 mph which I figured there would be if it was a u joint.

 

[inkpot]

Identify/eliminate ujoint issues by greasing one joint at a time and then test drive. No difference: grease one more joint and test drive again.

 

[lumbee1]

thanks guys I'll see if I can take a closer look at my U joints.

It feels more like a tire issue to me, I just wasn't sure if tire vibration would be more of a constant hum instead of this sort of pulsing.

It almost feels like there is some sort of weird resonance happening from the tires.

There is absolutely zero sign of vibration below 65 mph which I figured there would be if it was a u joint.

I had a nasty scraping sound when backing up. I took a look at my u joints and didn't see anything wrong with them. I added grease and the noise never went away. I forgot about it and the noise eventually did go away on its own until a few months ago it returned louder than ever.

I didn't know the conditions of my u joints but they looked great on the outside. The noise was definitely coming from the rear so I purchased new u joints from Cruiser Outfitters. I removed the front u joint and it was in great shape. Lots of grease and very tight. I removed the second u joint and when I did one of the caps fell off. The cap was bone driy and the needle bearings had turned to rusty dust. The grease port to the cap was jammed. The other caps were fine.

With the new u joints installed , the truck drove smooth on the highway with no noises.