Based on the number of new GTO owners coming into the forum and questions about the correct alignment process I have updated this post and included a link to the Holden documentation. I'll leave the link to the PDF up as long as there are no complaints from GM USA, GM AU or Holden.
There are four separate elements in the alignment process for a Pontiac GTO.
1. Front Cradle
2. Rear Cradle
4. All Wheel Alignment
These individual alignments work together to bring the entire drive-line and all four wheels on to the center-line of the monocoque structure. You can and will feel the difference.
1. Improved tracking under all conditions
2. Reduction in drive-line vibrations
3. Even tire wear
4. Reduction in rear wheel tramp
5. Balanced wheel well clearance
6. Correction of Strut Rub
First, we’ll discuss Front Cradle Alignment. The front fixture is essentially a large dial indicator.
This is a factory specified procedure and there is the factory stamped alignment mark covered by the skid plate.
The fixture needle should align perfectly with factory stamped mark.
Much like our rear cradles the front on this vehicle (Brad and Amanda’s 2004 GTO with about 5, 000 miles at Waukegan Tire Saturday, September 16, 2006 10:00 a.m.) are well out of spec. Alignments are tight and within tenths of a degree. This front cradle is out by ¼” according to the observations of the owner. Correction is accomplished by manually adjusting the front sub-frame and replacing the four TTY bolts so that the needle is directly aligned with the factory mark.
Why has this procedure not been available in the USA until now?
While we were aware of the procedure and the need the tool was not available. The tools are now available at your local Pedders Dealer. With their expertise and the right tools your GTO will drive better-than-new.
How many front cradle alignments using a fixture have performed in North America?
Two -- Amanda and Brad’s and my car. The question is who will be next?
When can I have this done on my car?
The tools have been shipped or are being shipped to your local Pedders Dealer. All the Pedders Dealers should have this tool before October 1st. You should be calling to schedule your appointment now.
Will this tool be available at the Pontiac Dealer or my local alignment shop?
Only if they can find another source for the tool. This is something we have been working on for a very long time. It is another reason we believe there is no substitute for visiting a Pedders Shop. They are suspension and in this case GTO Specialists who invest the time in education, tools and parts to service their customers.
Can a shop align my font and rear cradles without fixtures?
Maybe – there are certainly experienced race car techs working out of dirt floor garages that can align almost anything with wheels using strings and levels. Using a fixture is Holden’s solution to the most cost effective, accurate and repeatable sub-frame alignment process. If your sub-frames have been aligned using anything other than fixture, they may or may not be right. If they were aligned with a fixture they are dead nuts spot on.
Next is the rear cradle alignment and that requires the replacement of two TTY bolts in the sub-frame and four differential carrier TTY bolts. While this process is in progress it would be an ideal time to replace you sub-frame connectors. The triangulated plate is off, the TTY bolt has been broken loose so why not pry out a major source of rear wheel hop? Sorry for the digression. The rear sub-frame alignment differs in that there is no indicator. This is a four datum point fit fixture that can only be inserted into all four holes when the cradle is in full alignment. Once the fixture is in place the bolts are tightened. This process brings the rear sub-frame and differential into alignment with the center-line of the vehicle.
The third phase is the alignment of the transmission cross-member. With the front and rear cradles aligned by fixture the transmission cross-member can be properly centralized. This third step in alignment brings another elements of the drive-line on center with the related vehicle components.
The fourth phase is to centralise the the differential mount. The objective is a vehicle that performs with incredible precision and minimal vibration. We are dealing with a four thousand pound load that has a minimum of 350 HP.
The final step is the four-wheel alignment. This step can only be properly completed if the cradle previous three steps have been followed and all the related suspension components are within OE or better yet Pedders specification. Ride height, strut mounts, tie rod ends, ball joints, radius rod bushes, and so on must be in excellent condition. There is no reason to perfectly align a vehicle with worn suspension parts. The alignment will not hold under operational conditions because there will be excessive travel in the geometry. Your Pedders professional will walk through each suspension component and explain the condition to you with the car in the air. In Australia, we call this a 28 Point Check. There are actually more than 28 points but that is another story. The stock GTO does not have front castor or rear camber adjustment. These adjustments will require the addition of Pedders Alignment Bushes EP9166 and 5403. Your GTO can now be aligned to the factory specs or tweaked for a more aggressive spec using the Pedders Alignment Specifications.
Link to the Original Holden Procedure:
Will you be able to tell the difference in your GTO?
Only if you are breathing when you return from your test ride!
Medical Warning: People with high blood pressure and heart conditions should use Pedders parts with extreme caution. Pedderised GTOs have been know to result in extreme SEGs. If your SEG persists for more than 4 hours consult a doctor immediately. Severely dilated pupils may result from the adrenaline rush on your first drive of a Pedderised GTO. These medical side effects will last for years.
How much will this cost?
This is not a $79.99 Sunday Paper Special. The cost will vary from coast to coast. We have shops with hourly rates as low as $65 and as high as $140. The cost of real estate and local wage rates are the major factors in hourly rates. The service you receive from any Pedders Dealer will be the same – excellent. If you have a Pedders issue that cannot be resolved to your satisfaction with the dealer call or PM me. This is an hourly breakdown.
Front Cradle 2 ½ Hours
Rear Cradle 3 Hours
Transmission 1 Hour
Four Wheel Alignment 1 Hour
Each Pedders Dealer will set their pricing, but we will all be working from the same hourly base. Check your regional forums. My guess there will be posts from your local Pedders Dealer with package pricing. While they have the car on the rack and the TTY bolts out it would be the ideal time to upgrade your GTO and join the Pedders NATION!