Diagnosing a vibration/shudder on the front/front right wheel

[senso]

Good morning,

So, for the past months my MK4 Jetta developed a vibration/shudder when going around 60-80kmh(37-50mph).

I meet with a friend that has an elevator and after some poking around, we found that the transmission mount was way too sloppy, 40€ for a new one, rotated the tires, aligned the steering, and saturday(the day we did all this) and sunday the car was straight and there was no torque steer, tested it on the high-way, and even hit my personal speed record(210km/h, at 4700rpm, damm short gearbox the car is pretty stable at speed, and there is no extra vibrations after I break the 120km/h(60 mph) barrier ).

Today coming for work, its back, if I'm not holding the steering wheel the car will start to veer right, and if I step on the gas it will go out of the lane in some 20-30 meter(65-100 feet).

I dont think that its a CV joint, because doing roundabouts up to 80km/h(50mph) there is no noises, but there is a cyclic noise that is more evident when I press the brake pedal.

Maybe its the crappy lower control arm bushing, I replaced everything last year, but they are Moog parts, and I can kick the right side wheel and there is movement, while there is none on the left side wheel, the big round bushing are also cracked already.

Any ideas on what this can be?

Best regards.

 

[Tdijarhead]

Tire, inner or outer tie rod or wheel bearing. Rubber bushing will look cracked sometimes but in fact not be, but probably worth checking. Here in the states Moog parts are usually ok. I use them on some of my other vehicles, not my vw though.

 

[senso]

I read somewhere, not sure if here, or on other forum that Moog parts where not so good sometime around 2017, either acquisition or they changed manufacturing to China/lowered their QC.

The thing is that there is no extra noises besides the vibration, and I don't really like to throw parts at it without needing, I will try to get the car in an elevator and bag everything around with a rubber mallet.

I suspect that the engine mount is an effect and not the real culprit.

Also, I forgot to add, my gearbox started leaking on the right side transmission, maybe its the gearbox/diff bearings?

There is no play if I jack the car up and try to move the cv's/trans-axles, but I was saving up to swap my gearbox with a 6 speed one, that would rule out a lot of culprits, and I don't really want to sink money into this one :/

Thanks for your thoughs Tdijarhead, will check the tie-rods when I jack it up.

 

[Tdijarhead]

Yeah Moog like almost everyone else is off loading some of there manufacturing to China. That’s why I said usually ok. You just have to watch what you buy and where it’s from.

I had an inner tie rod that would allow a vibration to happen only on a left curve. Took me some time to find that one. Turned out to be one of the worse inners I’ve ever seen.

 

[senso]

Made the drive home with the radio off, when I brake there is definitively a shake that is stronger the harder I press on the brake pedal, there is also a cyclic sound when I do thigh corner at speed to the right.

This is driving me crazy :/

Waiting till the weekend to visit my machinist friend and put my disc brakes in the lathe and indicate them.

I have the "old" ones they only have a 2mm wear, but I'm a bit weary on slapping the discs on my current pads, because the current ones already have some 10k km's in them.

Its something cyclic, so even though there is no horrible noises, I'm starting to doubt either the CV's or the wheel bearings, but thats a 300€ shotgun approach with zero guarantees that it will fix anything.

 

[Tdijarhead]

Ok a shudder when you push on the brake is often a brake rotor. I had a set of new Chinese rotors die in less than 5k miles. That taught me never to buy important parts for my car like brake, bearings, timing belt parts etc that say made in China.

 

[tgray]

A shudder when the brake is pushed means to start looking at the brake unless the wheel bearing is all loose. I have had bad break pads themselves cause shudders like that. Sometimes a sticking caliper heats up and warps the rotor and weird things happen. If everything it tight, no change when tires are changed, it sure sounds like a rotor/pad issue. wheel bearing will usually sound like a train or growling sound. Axle shafts will jerk, clunk or knock when they go out.

 

[tgray]

I have seen the china junk rotors that looked like they had parts of old tools melted into them. Others have pockets of air bubbles in the surface area. Pay a little more and get better name brands and see them work way better.

 

[eb2143]

Double check the wheel bolts are still tight.
Odd that you did the repairs and had one good day without any obvious issues and now have very obvious issues.

 

[KrashDH]

Made the drive home with the radio off, when I brake there is definitively a shake that is stronger the harder I press on the brake pedal, there is also a cyclic sound when I do thigh corner at speed to the right.


Its something cyclic, so even though there is no horrible noises, I'm starting to doubt either the CV's or the wheel bearings, but thats a 300€ shotgun approach with zero guarantees that it will fix anything.

In my experience, wheel bearings have never been a cyclical sound. It's a loud "whirring" or "drone" that you can hear when the vehicle is loaded. Also I know with these cars, I believe the wheel bearing that's bad is the opposite one than the one being loaded when you hear the noise. I had this happen and I replaced both and was good to go.

I had to replace my right and left CV's and they were both cyclical noises and they were both the same noise when they failed. They both went from bad to worse VERY quick, as in I did about 30 miles to work and 30 home and I didn't want to drive the car until they were fixed. After i was able to hear the clicking I got the car up on jack stands, pulled the pan, and got under there and reafed on those suckers as hard as I could in every direction to feel play. They both had play that didn't seem like much but when it resonated through the cab it was emphasized. Note that these failures weren't at the same time.

The pulsating in the brakes to me would be a warped rotor. Pretty easy to throw an indicator on those and measure the runout.

FWIW, I wouldn't put a moog component on any of my vehicles unless I wanted to do the job over again quickly.

 

[senso]

Double check the wheel bolts are still tight.
Odd that you did the repairs and had one good day without any obvious issues and now have very obvious issues.

I might not have had a good day, I was soooo happy that is was shaking/vibrating like mad under acceleration that I might not have noticed the now evident vibration, if its understandable.

The rotors are supposed to be from Brembo, but they where bought online, and only costed around 60€, and do work them out from time to time, so it wouldn't surprise me that they are knock-offs, and they warped after some time, the surface looks decent, but its on my to check list as soon as I can.

Thanks for all the info/things to check!

 

[BobnOH]

This is not easy diagnosis over the interweb.
I might take it to a good alignment shop, much of their process is inspection.
A brake rotor would have to be pretty warped to cause vibration at speed, unless the brake is hanging up, slider pins or even stuck caliper.
From reading here, that type of shudder, seemingly warped rotor, is often worn control arm bushes.

 

[flashmayo]

Rotate the 2 front tires side to side and see if the symptoms follow. I could see having a tire with a delaminating issue cause the vibration at speed, and the vibration felt in the brake pedal points to a rotor issue.
Try the rotate tires test, if you get a change, put on the spare or take the tire in to have a tire pro look at it.
If you still have the vibration felt in the brake pedal, do a complete brake job with quality components. Rebuild or at least service the calipers, cut the rotors as a test or just replace, inspect the pads, replace as needed.

-JT

 

[wonneber]

I can kick the right side wheel and there is movement, while there is none on the left side wheel, the big round bushing are also cracked already.

You get movement on one side but not the other?
I would search where the movement is coming from.

 

[xjfish]

Stuck caliper or dragging brake seems likely. After a drive, hold your hand near the front wheels to check for any difference in temp. (or preferably use an infared temp gun) Wheels should spin freely with minimal drag off the ground...

 

[pdtdiarl]

Usually, when you step on the gas and the cars turns left/right, its control arm bushings, simply because they hold the wheel horizontally, which they can let the wheel go back/forward (left/right). Steering rank and other ball joints could do that, but you would hear it louder noises.

Try this:
https://www.youtube.com/watch?v=83Pw3V8pMeI