Damn Front End Shake

**surfinjoe** · 07-29-2008, 04:58 AM

I have been fighting this shake all summer. Took my car down to the Pedders guy's and they couldn't find anything wrong with the car. I have tried the following things to no avail:

1) New tires
2) Dynamic road force balance
3) Alignment (4 wheel and X-member)
4) Check wheel hubs & rotors for flatness & bad bearings
5) Clean rotor face/hub & hand torque
6) Pedders fix (radius rod bushings & X-member bushings)
7) Inspect the strut bearings (myself & Pedders shop)
8) Inspected the rims (one was bent, but I replaced it)

Anyone got any other ideas? The car starts to shake at 60 MPH and gets worse the faster you go. The wierd thing is that it comes and goes. Sometimes when you round a corner it goes away (or comes). Sometimes you round a corner and nothing happens. Sometimes it shakes when you are running straight. Sometimes it shakes alot and sometimes it shakes a little. WTF is going on with this damn car.

**Sarge** · 07-29-2008, 05:28 AM

You know ...sometimes you just need to take it to the experts. Take it the nearest Pedders dealer and get it fixed once and for all.
http://www.peddersusa.com/dealer-finder/48

**Vexzer** · 07-29-2008, 06:43 AM

I know this is a stretch but look for debris in the brake rotors. Once my Suburban's wheels were stolen and the front end dropped in mud. After that it had strange vibrations I could never fix. One day I was doing the brakes and noticed the rotors had mud caked in them. Chipped it out and troubles went away.

That's prob not your problem though, hard to believe you would have not already stumbled across a rock or something in a disc. What about the driveline?

**surfinjoe** · 07-29-2008, 06:51 AM

Sarge - I already took her to the Pedders guy's. They put her up on the hoist and couldn't find anything. They aligned the X-member and sent me on my way. It didn't fix anything.

Vexzer - I'll look again at the rotors for rocks and such, but my issue comes and goes. It feels like something is worn or loose and only breakes free at higher speeds. I have no idea what in the driveline could cause this type of looseness in the front end (I am assuming at this point that it is a front end issue). The bent rim just happened to be on the left rear side of the vehicle.

**Wesman** · 07-29-2008, 09:05 AM

Check your motor mounts. Its very unlikely that one would break, but its still possible. Its also a possibility that the rubber insert is worn out and there is metal to metal contact in the mount, which would cause a vibration.

**5.7literMustangEater** · 07-29-2008, 09:39 AM

Just throwing an idea out there. I know this is frustrating and all, I went through the same BS with the front end shake, but it actually turned out to be a bad tie rod end that was causing my shake. I would check you tie rod ends up front. One of mine had a busted bushing and was causing my front end to shake under high speed braking. I got that replaced and haven't had a single shimmy, shake or vibration. I couldn't believe it!!! Finally after months of being pissed at the car my problems were solved. I would just give it a look see. Hope this helps, I feel your pain though brotha!!

**PartsGedder** · 07-29-2008, 07:25 PM

Have you nut and bolted all of the suspension bits? Struts, radius rods arms, control arm bushes, etc.
It could be a failed strut in addition to any of the other suggestions posted.

rednari · 07-29-2008, 08:08 PM

Shakes can be frustrating. But, you should run more tests to breakdown the problem before spending anymore money. You seem convinced that the problem is in the tires and/or suspension. Maybe or maybe not.

First, if you are relating correct facts we know: 1. That it is intermittent and sounds like somethings which loosens or triggers the vibs under certain conditions. 2. What are those conditions? 3. Try braking when the vib starts and note the response. 4. Put the car in neutral when the vib starts and note the response. 5. Push in the clutch and rev the motor etc. 6. Switch the tires from front to back.

This will help you isolate the area. Also, you stated you had a bent rim, which means you hit something hard. On what side or position was the tire when it became bent? What did you hit? Did the vib start right after the hit.
Good luck and let us know what it is.

**surfinjoe** · 07-30-2008, 05:41 AM

I have an A4 so no clutch to play with however I have put the car in neutral at high speeds (while the shake is occuring) and it does not make the shake go away. I have already rotated the wheels from front to back and this did not help either. The next thing I will try is braking during the shaking to see what happens.

I will also take a look at the tie rods however I would hope that the Pedders guy's would have checked this when they set the alignment (yes or no?).

Thanks for all the feedback. I'll keep looking into everything and see what I can come up with. What a PITA!

Originally Posted by rednari

Shakes can be frustrating. But, you should run more tests to breakdown the problem before spending anymore money. You seem convinced that the problem is in the tires and/or suspension. Maybe or maybe not.

First, if you are relating correct facts we know: 1. That it is intermittent and sounds like somethings which loosens or triggers the vibs under certain conditions. 2. What are those conditions? 3. Try braking when the vib starts and note the response. 4. Put the car in neutral when the vib starts and note the response. 5. Push in the clutch and rev the motor etc. 6. Switch the tires from front to back.

This will help you isolate the area. Also, you stated you had a bent rim, which means you hit something hard. On what side or position was the tire when it became bent? What did you hit? Did the vib start right after the hit.
Good luck and let us know what it is.

**surfinjoe** · 07-30-2008, 05:48 AM

The drivers rear rim was bent (3" flat spot) on the inner part of the rim. I purchased the car used and the rim must have been bent before I purchased it. I replaced the rim with a new rim and the shake did not go away (but it did get a little better). I also replaced all 4 tires and got a road force balance on them so the tires/rims should not be the issue.

I only notice the steering wheel shake at highway speeds (60 MPH+) however I can feel a slight vibration that starts around 35 MPH. If I hold the steering wheel still (at highway speeds) it will stop shaking, but I can still feel the vibration.

**surfinjoe** · 07-30-2008, 05:51 AM

I have installed the Pedders radius rod bushings, sway bar bushings and WILL soon replace the inner radius rod bushings so I should be OK there. I had the Pedders shop check the struts as well as checking them myself (everything was OK). I did not have them check the control arm bushing or tie rod ends however the 4-wheel alignment SHOULD have picked this up. I also installed new X-member bushings and got a cradle alignment.

Originally Posted by PartsGedder

Have you nut and bolted all of the suspension bits? Struts, radius rods arms, control arm bushes, etc.
It could be a failed strut in addition to any of the other suggestions posted.

**JusticePete** · 07-30-2008, 08:34 AM

The vibration comes and goes at different speeds so that tell us it is rotational. You can drive through the vibration. correct?

**JusticePete** · 07-30-2008, 09:21 AM

Originally Posted by surfinjoe

Sarge - I already took her to the Pedders guy's. They put her up on the hoist and couldn't find anything. They aligned the X-member and sent me on my way. It didn't fix anything.

Vexzer - I'll look again at the rotors for rocks and such, but my issue comes and goes. It feels like something is worn or loose and only breakes free at higher speeds. I have no idea what in the driveline could cause this type of looseness in the front end (I am assuming at this point that it is a front end issue). The bent rim just happened to be on the left rear side of the vehicle.

Let's get your car back to the Pedders shop and have them call me when you are in the shop together with the staff.

Mobile 616.834.8100
Office 248.522.8021

**surfinjoe** · 07-30-2008, 09:35 AM

What do you mean by drive through the vibration? If you mean does the vibration go away when I hit X speed, the answer is yes and no. The vibration changes and seems to improve around 100 MPH but does not go away.

I believe that I am dealing with two issues here:

1) An SOTP vibration that is felt at all speeds
2) A definate 'steering wheel shake' that comes and goes

I am sure they are related, but I always seem to have issue #1, and issue #2 comes and goes.

Clear as mud?

Originally Posted by JusticePete

The vibration comes and goes at different speeds so that tell us it is rotational. You can drive through the vibration. correct?

**JusticePete** · 07-30-2008, 09:38 AM

Originally Posted by surfinjoe

What do you mean by drive through the vibration? If you mean does the vibration go away when I hit X speed, the answer is yes and no. The vibration changes and seems to improve around 100 MPH but does not go away.

I believe that I am dealing with two issues here:

1) An SOTP vibration that is felt at all speeds
2) A definate 'steering wheel shake' that comes and goes

I am sure they are related, but I always seem to have issue #1, and issue #2 comes and goes.

Clear as mud?

Do you have an OE or after market drive shaft?

**surfinjoe** · 07-30-2008, 10:33 AM

I will schedule a time with Victory Racing and get my car back up on the hoist. I'll have them give you a call when they do. Thanks!

Originally Posted by JusticePete

Let's get your car back to the Pedders shop and have them call me when you are in the shop together with the staff.

Mobile 616.834.8100
Office 248.522.8021

**surfinjoe** · 07-30-2008, 10:34 AM

I have the OE 2 piece driveshaft.

Originally Posted by JusticePete

Do you have an OE or after market drive shaft?

**JusticePete** · 07-30-2008, 11:19 AM

Originally Posted by surfinjoe

I have the OE 2 piece driveshaft.

Brakes are OE too?

**JusticePete** · 07-30-2008, 11:19 AM

How many miles?

Do you have the Road Force numbers for each wheel?

**surfinjoe** · 07-31-2008, 06:12 AM

Pete - Brakes are OE, rims OE, Tires are new (Kuhmo). I think I have the road force balance sheets for the tires. The car has ~20K miles of easy driving.

I took the car on a ~200 mile road trip today and noticed that braking does not improve or worsen the shake. The one thing that does change the shake is going around a corner. This can make the shake come or go, but there is no particular trend (like every time I turn left it goes away).

The steering wheel seems to exhibit two issues:

1) Shaking fast at highway speeds
2) Slowley rocking right to left at highway speeds (kind of loping)

Let me know if this info. helps. Thanks!

Originally Posted by JusticePete

Brakes are OE too?