Front End Shake On 2004 GTO

**surfinjoe** · 01-15-2008, 07:32 AM

I have a '04 GTO and the damn thing shakes at highway speeds (60 mph+). Does anyone know what may be causing this? It doesn't shake all the time, but when it does it is really annoying.

I also seem to have uneven front tire wear (toe'ed in).

I only have 16K miles. Please help!

**Sarge** · 01-15-2008, 04:00 PM

Couple of things first....get them road forced balanced....if they still shake check your Radius Rod Bushings.....do the 5mph test.....have somebody look as you get up to 5mph and slam on the brakes...if your tire goes back a little bit and then pops back...you probably have shot RR bushings....also check your top strut mount bushings....see if the are shot...you can tell easy....if the inner part is higher than the outside part of the bushing...they are shot......and dont run over the poor son a bitch that is watching your tires to see if they move when you brake....

**surfinjoe** · 01-16-2008, 05:06 AM

Thanks Sarge! I will give it a try. Are these issues common for the '04 GTO's? I am very surprised to be checking for these things on a car with 16K miles.

**Sarge** · 01-16-2008, 07:57 AM

Yes common on 04/05/06....listen the bushings on these things are garbage. I have seen Strut Tower bushings shot to hell with less than 5K miles on a new 06.
When your bushings are garbage the wheel moves around/the alignment is out of whack/nothing good....you can do serious good with around $300 worth of parts and an afternoon with no special tools or lifts required.....check out my Front End Pedders install thread....I bet your Radius Rod bushings are causing your shake....

**PartsGedder** · 01-16-2008, 05:11 PM

surfinjoe - Did you check the normal suspects? lug nut torque and clean the hubs to get any excess gunk off of them. Check the ride height to see if it has settled any, should be 604mm on 17" rims, 616 on 18" rims. If this is all good, then go after the bushes and others. Radius rod bushes will thorw camber out of whack and the stut bushings, well, are pretty prone to failure. Like Sarge said, don't run over your spotter in the 5 mph test.

**0rion** · 01-16-2008, 11:32 PM

I guess I never knew any of this........learn something every day. My car is pretty rough when it's cold for the first few minutes and then it's smooth as silk after it warms up, always worse when the weather is really cold. I've always known something wasn't quite right with it but have never been sure what it was. These 2 things sound like possible suspects. I'll have to check it out.

**starcheif** · 01-17-2008, 04:54 AM

Yeah mine does it as well. I now have 38,000 miles on my 04 and it all started after i rotated the tires. It gets really bad when i hit the brakes or when i'am cruising on the freeway about 55 to 70 mph but then smooths out after that. I just thought the front tires needed to settle in but now i will have to investigate some more. Good post thanks for all the input.

**surfinjoe** · 01-18-2008, 07:04 PM

Thanks for all the input. Once it warms up in Michigan (mid-March hopefully) I will start to problem solve. I will post feedback once I find out what is going on. Thanks again!

**Raoul-Duke** · 01-19-2008, 05:15 AM

Originally Posted by Sarge

Yes common on 04/05/06....listen the bushings on these things are garbage. I have seen Strut Tower bushings shot to hell with less than 5K miles on a new 06.
When your bushings are garbage the wheel moves around/the alignment is out of whack/nothing good....you can do serious good with around $300 worth of parts and an afternoon with no special tools or lifts required.....check out my Front End Pedders install thread....I bet your Radius Rod bushings are causing your shake....

honestly sarge i think mine are fucked too. these are the symtoms. you can give the diagnosis....my alignment is off, and at speeds at 60mph+ my steering wheel will shake and vibrate very very slightly.. but around 80-90mph it will do it a lil more. and 80% of the times when i brake at higher speeds it will rock back and forth more harder then when accelerating...ive got 30k on the clock

**Sarge** · 01-19-2008, 06:13 AM

Guys these bushings are the culprit. You can get alignments and balance the tires every 5 minutes and the bushings allow the wheel to wander all over everywhere.
I tell you for small $$ and an afternoon...you can change the performance of your suspension to levels you did not know where possible and eliminate strut rub/vibrations and improve your braking. No shit.
And another thing....The Pontiac dealers know shit about the suspension on our cars....much less how to diagnose anything like vibration/shake.....I talked to my dealer about the imporvements from the bushings and they were like "No shit"...."I didnt know".....

**PartsGedder** · 01-19-2008, 07:57 AM

Originally Posted by Sarge

We measured from the bottom of the wheel to the bottom of the fender well...and it looks like it raised it about 15MM.....

The 15mm difference is after Sarge replaced the Strut Bushings and bearings. If the radius rod bushings are shot, it'll mess with camber. 15mm drop in the front, caster out of whack and the car handles accordingly, vague, front end moves around, won't hold alignment, etc.

Measure the ride height, do the 5mph test, go from there. If the wheel moves excessively, radius rod bushings are shot. Ride height change could be a lot of things gone wrong, but the Strut bushings are a good place to start looking.

**Raoul-Duke** · 01-20-2008, 03:43 PM

Originally Posted by Sarge

Guys these bushings are the culprit. You can get alignments and balance the tires every 5 minutes and the bushings allow the wheel to wander all over everywhere.
I tell you for small $$ and an afternoon...you can change the performance of your suspension to levels you did not know where possible and eliminate strut rub/vibrations and improve your braking. No shit.
And another thing....The Pontiac dealers know shit about the suspension on our cars....much less how to diagnose anything like vibration/shake.....I talked to my dealer about the imporvements from the bushings and they were like "No shit"...."I didnt know".....

soo i guess im gonna do this once it get a lil warmer in chicago. hey sarge what do i need and where could i find everything need for this job??

**Sarge** · 01-21-2008, 02:44 AM

Click on the sponsor link here in the GTO section. Easy job. Limited cussing required

**JusticePete** · 01-21-2008, 08:50 AM

We have separate issues in this thread: Vibration, Tire Wear Braking Motion.

Vibration -- Road Force Balance to establish the tire and wheel are not the source. Get a printed report for each wheel.

Remove your front wheels, Unbolt the brake calipers. Pull the rotors. Using a spinning wire wheel brush and clean the inside of the hate and the face of the wheel bearing to clean shiny metal. Do the same to the outer face of the hat. Use a smear of anti seize on the bearing face. Reinstall the hat and caliper. Put the wheel on with three lugs. Tighten them sequential with your fingers, then incrementally with a wrench and finally torque them up in a rotational pattern in 5 pound increment to 90 pounds. Add the two remaining lug nuts and tighten them the same way. Test drive the car. You should be good to go.

Tire Wear -- The GTO front struts have a comfort bias on the critical damping scale. They wear. A worn strut cannot hold the tire flat against the road surface. The OE radius rod bushes are less than robust. They allow the radius rod to move forward and backward -- excessively. These changes in castor make alignment work a moving target. The strut mount is a wear item no different that a brake pad or tire. They require maintenance. Add these two factors together and you get tire wear.

In my opinion, If you have a GTO and have not replaced your radius rod bushes -- yesterday would have been the best time to do so.

Strut mount wear is diagnosed with ride height ,measurements, 24mm wrench spring back test and a visual inspection of the mount with the upper strut nut and retaining plate removed. Any time a strut comes out of a GTO for service, the strut mounts should be replaced. They performance a critical function in locating the strut shaft. Improper strut placement from a wrong or failed strut mount can lead to major strut rub.

Excessive body Motion on braking -- This is the front radius rod bush. The OE bush is expenssive and hydraulically damped. The fluid i glycol based and water soluble. Unless you test your RR bushes when they are fresh, you will not see any fluid be forced out -- because it ha probably been pumped dry. You can observe the motion between the rear of the front tire and the fender line. In 5MPH panic stop the wheel should move about 10mm. On a worn RR bush car the wheel will comethisclose to touching the painted fender edge. Replacement radius rod bushes will correct this. Some vehicles also suffer from rear radius rod bush failure. This is solved with on outer control arm / rear radius rod bush replacement.

The bushes are relatively permanent solutions. They will last a long, long time. The wheel lug nut torque and hub face cleaning is not permanent. If the vibrations returns move the wheel one lug clockwise and torque as described above. You should have excellent tire wear and close to vibration free driving.

**JusticePete** · 01-28-2008, 09:29 AM

So life is good and you are vibration free?

**surfinjoe** · 02-26-2008, 06:54 AM

Justice Pete - can you provide the correct part number for the front radius rod bushings?

**LS16SPD** · 02-26-2008, 11:45 AM

Definately Sounds Like Bushings

**Sarge** · 02-29-2008, 03:56 PM

Here are the correct parts. Check out the install thread in the stickies. HUGE improvement guys...and a easy install....
http://shop.rocksandracingllc.com/pr...5&productId=61

**surfinjoe** · 03-03-2008, 07:11 AM

OK guy's, I just ordered the Street 1 package to make it simple. I also ordered the rear radius rod bushings and the front & rear sway bar bushings for good measure. I hope this fixes my issue and makes the old bitch corner more like my '01 SS did.

I am waiting for the weather to clear here in Michigan, so it may be 3-4 weeks before we have a nice day to work on her. I also have a Magnaflow cat back, CAI intake and Diablo 2 programer to help with the HP side of things. Should make for a busy weekend when it's all said an done. I will post some feedback when I finish.

Sarge - thanks again for your advice. I sure hope this works.

**cardude365** · 02-06-2012, 11:28 AM

Originally Posted by Sarge

Yes common on 04/05/06....listen the bushings on these things are garbage. I have seen Strut Tower bushings shot to hell with less than 5K miles on a new 06.
When your bushings are garbage the wheel moves around/the alignment is out of whack/nothing good....you can do serious good with around $300 worth of parts and an afternoon with no special tools or lifts required.....check out my Front End Pedders install thread....I bet your Radius Rod bushings are causing your shake....

I'm not experiencing the tire wear just loud ass humming noise from front end and under car (very slight shake) , I thought it was the carrier bearing at first but now I Have doubts. It happens loudly at slow speeds 5-10mph and hums wildly at 70-80mph, I have also noticed the speedometer does not seem to be accurate of about 5-7mph compared to my gps and seems to get worse the faster I go. Stock tire and wheel size and as far as I know stock gears. (wtf)? I am very frustrated by this I love the car (power and handling) and most of the other features seem of good quality. (exception of the Key) If i cant figure this thing out I'm going to off it and stick with my "00" SS and I don't want to spend big money to fix this bitch. I am irritated I am having problems like this with 40k miles. No wonder these pieces of shit sold so badly.... every time i drive this thing some one asks me if my wheel bearings are bad, wha.... wha.... wha... wha..wha. wha. wha whawhawhawha. It seems this will be the Last Pontiac I ever own, if i can even sell it and not loose my ass will be a wonder. I'll probably have to gear up in my motorcross gear and wad this fucker up, whoo hooo here goes my insurance rates......... Help if you can guys sorry I have a bad outlook I'm just frustrated.