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GTO Alignment Process

48K views 163 replies 55 participants last post by  dms 
#1 · (Edited)
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
3. Transmission
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!
 
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#2 · (Edited)
My car has been waiting for that tool for 3 months now. The car is pissed! LOL! I am patient.

Heading to Rossi as soon as Frank recovers from the punishment of vacation. You know I am the one that caused the need and I am next! LOL!
 
#112 ·
Unless I am missing something... it looks like it would be quite easy to fabricate this tool.
 
#5 ·
That looks handy for a center line measurement.
Now, is there a fixture to reference longitudal offset as well?

If the front subframe isn't centered AND "squared" the wheel base and caster angles could be off. If there isn't another tool, I guess we'll continue to use a tape measure and reference holes in the unibody for "setback" measurement.

The rear cradle fixture references both axis. That's one nice thing about it.

How is this being handled in AUS?
 
#7 ·
SoCal Goat said:
That looks handy for a center line measurement.
Now, is there a fixture to reference longitudal offset as well?

If the front subframe isn't centered AND "squared" the wheel base and caster angles could be off. If there isn't another tool, I guess we'll continue to use a tape measure and reference holes in the unibody for "setback" measurement.

The rear cradle fixture references both axis. That's one nice thing about it.

How is this being handled in AUS?
There are four bolts that attach the front cradle to the body 'frame' member. One cradle hole is round and the other three are elongated. The round hole is the pivot point and precludes a longitudinal adjustment.

It should be handled the same way. Holden wrote the 'book' on it.
 
#8 ·
i forget who the pedders dealer in NJ is. I wanna say rossi am i right?
 
#9 ·
avovom said:
i forget who the pedders dealer in NJ is. I wanna say rossi am i right?
It used to be Frank something or another but he went to Florida on a two week vacation so all of his business has been transferred to Mike White in California. I like Mike -- he isn't on vacation and he told me he was the closest dealer too. :gr_devil: :gr_jest: A complete Pedders Dealer List is available on our website. Most of them answer their phones FRANK!!!!!!!!!:stickpoke

Please call Frank right now. It is his 9th anniversary and they are having dinner or maybe something else by now. His wife is a Saint to stay around that long. :angel: So EVERONE CALL FRANK NOW!!!!

Frank J. Beck
Rocksand Racing, LLC
ROSSI CHEVROLET BUICK PONTIAC GMC SUZUKI Inc., Washington, NJ
30 Route 31
Washington, New Jersey 07882
fbeck@rossisuperstore.com
www.rossisuperstore.com
Office: (908) 892-1882
Fax: (908) 689-7871
 
#12 ·
OMG thats funny i'd rather wait around 11 ish to call. that will get him a lil ticked off don't ya think?
 
#22 ·
spd98 said:
does vengance has these tools now? The didn't last time I was there.
They have the rear and will have the front in a week. Waukegan Tire got theirs personally delivered because Ken threatened to beat me with a DoquTorq wrench. Mike White's shipped yesterday because he lives in lala land and it takes forever to ship them anything and SWMN is dropping his car off on Saturday.

Seriously, the tools ship out to our dealers next week with the two exceptions above. Call your local Pedders Dealers to schedule your alignments.
 
#23 ·
How common is it for GTO's to need the front cradle and transmission alignments? Are those two types of alignments more or less common than the all wheel alignment and the rear cradle alignment? Thanks in advance for the info.
 
#24 ·
damon_Z said:
How common is it for GTO's to need the front cradle and transmission alignments? Are those two types of alignments more or less common than the all wheel alignment and the rear cradle alignment? Thanks in advance for the info.
The rear cradles are almost never dead nuts on (the fixture fitting without adjustment). The fronts are essentially 'self aligned' at the factory with 'self-centering' lead bolts. That means the front and rear are within factory tolerance but not dead nuts on. On Amanda and Brad's GTO that is about 1/4" off in the picture.

If you get in your car and turn the key, don't mod anything and enjoy the stock GTO you don't 'need' cradle alignments. If you drive aggressively, if you autocross, if you road race or if every day to work is a race you should have the service performed. You will feel the differnce.
 
#25 ·
damon_Z said:
How common is it for GTO's to need the front cradle and transmission alignments? Are those two types of alignments more or less common than the all wheel alignment and the rear cradle alignment? Thanks in advance for the info.
The short version is we don't know yet. The front cradle tool for 04/05/06 GTO just arrived in North America like two weeks ago. 1 car has been done. Do you see the SEG on those people?

The long version is I am fixing to find out.
 
#26 · (Edited)
My First GTO said:
YOUR DEAD.......LOL ....Frank
I'm sold... I hate to get my car aligned before winter, but I'm making an exception after seeing how misaligned it is. Frank, are you running a special on this??? I have high blood pressure and a heart condition so take it easy on me...
Here are the things I want done:
1. Front Cradle
2. Rear Cradle
3. Transmission
4. All Wheel Alignment
5. Oil/Filter change
6. Dexron VI transmission fluid change; manual trans.
7. Clutch fluid flush/bleed
8. Check my differential; it clunks
 
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