Post by TexasG8 on Jul 9, 2009 15:01:54 GMT -6
FRONT SUSPENSION PART 1
last year, I posted a similiar post that defines the concerns of the GTO suspension and offered solution to the concerns. i was asked to do this by moderators. Somehow, an error occured, and one of the moderators deleted the post. I spent a serious amount of time on this and left this forum. Today I decided to visit the forum again because Rob at Wretched Motorsports is a Pedders sponsor here. So i decided to revisit and will repost an updated definition/solution base for the GTO. Wretched Motors can offer you support to resolve any issues listed below. If allowed I will assist you as well.
I am well known in the GTO community and go by DMS, which stands for "Doing Mike's ****" I have dedicated a very serious amount of time, energy and conflict on the GTO and will pass on knowledge that I have on it. This forum has very little information on the GTO, and I feel this community can benefit by this info, just if it generates questions. So here we go!
The Definitive Explanation of GTO Suspension Concerns and Permanent Resolution Part One
This document was prepared to give the novice GTO owner a list of concerns common to the GTO suspension, and offer solutions to each problem.
FRONT SUSPENSION ISSUES
1. STRUT RUB
2. INSIDE TIRE WEAR AND CUPPING
3. NOISES
4. RIDE HEIGHT CONCERNS
5. BRAKING ISSUES
6 EXCESS SUSPENSION TRAVEL
7. EXCESS BODY ROLE
8. INSUFFICIENT NEGATIVE FRONT CAMBERS
9. POOR STRAIGHT LINE STABILITY
10. LOOSE STEERING FEEL
11. FRONT END NOT CENTERED TO THE BODY
REAR SUSPENSION ISSUES
1. INNER TIRE WEAR AND CUPPING
2. RIDE HEIGHT CONCERNS
3. POOR LAUNCHING AND EXCESS SUSPENSION TRAVEL
4. EXCESS WHEEL HOP
5. EXCESS TOE AND CAMBER CHANGE
6. EXCESS LATERAL SUSPENSION MOVEMENT
FRONT SUSPENSION SOLUTIONS
1. STRUT RUB. There are 2 kinds of strut rub on the GTO. When the GTO first came out, it was common to have strut rub, (tire to strut contact). In 2004 and early 2005, this was due to aggressive alignment settings for negative camber. Why was this a issue in the USA and not in Australia? Simple. GM added approximately 400lbs of structural support to the GTO so it would meed Federal criteria. Due to this, GM needed a larger capacity tire than the 235/45R17 used in Au. To try and increase tire life, GM went to a 245/45R17 tire which has a larger capacity rating, but is 10mm wider. The 235 has a load range of 1433lbs @ 44psi, and the 245 has a load range of 1521 @ 44psiWe initially saw strut to tire contact at the first rotation. GM was/is aware of this problem since the beginning but did not publish anything. If you called GM Technical assistance, they would tell you to put the front cambers to the positive end of specs, .2 camber. This strut rub would only cause a cosmetic issue, and is/was not destructive. This fixes the first style of strut contact, but severely reduced the handling. We have come up with a general spec to go negative on the cambers to the -.3 to -.4 range. At this range, you should be able to have at least a pencil width clearance between the tire and the strut. With that said, it is also CRITICAL to have your tire pressures at 35psi cold!!!. This fixes the first kind of strut rub, at least temporarily.
How many of you had not issues at at at the first tire rotation at 6,000 miles and the second one at 12,000 miles, but at the 3rd rotation at 18,000 miles the inner tire tread is destroyed, and there was evidence of strut to tire contact? You took it to the dealer and they said you must have hit something and knocked the front end out of alignment? Does this ring a bell to many of you?? Now i is true that you could have wacked something and knocked the front end out of alignment. But you also could have driven the GTO like a little old gramma going to Sunday school, and never hit a leaf in the road, and will still have the problem. Why? The strut bushing is damaged the moment it gets off the boat. To protect the front end, Holden installed front coil spacers to eliminate all front coil movement. Then they chained and cinched the car down really tight. The GTO was this way for over a month. This collapses the front strut bushing. But collapsing strut bushings is just the first issue, and by itself, is not that severe of a problem. But when collapsed, it weakens the rubber, and therefore the center of the bushing cannot stay centered in the bushing. This causes 2 issues. First it causes the strut shaft to migrate to towards the engine compartment, seriously increasing negative camber, as well as it will cause the camber to seriously change. The center of the strut bush, thus the strut shaft, will move all over the place, causing serious camber change, which ultimately causes serious toe change, which always screws up your tires.
Now for some controversy: When the strut shaft moves in and out with respect to the engine, this movement is rapid. It will also cause the tires to have excess sidewall flex. Add the normal sidewall flex of turning, and you now have a lot of sidewall movement: enough sidewall movement to cause the tires to kiss the strut. I have seen and documented a severely worn strut bush, causing major inner tire wear, and strut contact, with 1/2 inch clearance from the strut to the tire. The strut contact issue, however, is again primarily cosmetic and not destructive. The tire wearm however, is severe and is often interpreted as contact wear from the strut
So the primary fix will be to replace the strut bush, and bearing, which will most likely come apart once the strut is dissassembled, then re-align the front end to get -.3 to -.4 negative camber. This usually will give you the pencil thickness clearance.
All of us have seen the reallllllly serious strut rub that destroys tires. It is my opinion that this strut rub is only caused by major impacts and bent parts.
2. INSIDE TIRE WEAR AND CUPPING. The primary reason for inside tire wear is wear as a direct result of the strut bushing as previously mentioned. But there is another concern. You can see it by drivng your GTO 7-8mph then seriously jam on the brakes on. Observe the front wheels. It is not uncommon to see the front wheels kick back 2 inches. What this movement does is reduce braking action and brake pedal feel, but mostly causes major caster change, which again causes toe change. Toe gets toed out a lot. This again causes major tire wear, primarily on the inside and is a major contributor to tire cupping, which again is a major problem with the GTO. The cause of the excess movement is primarily the front OEM radius rod bushings that are fluid filled and often leaks, thus increasing the movement. The rear radius rod bushing also gets damaged and the washers bent due to the excess movement caused by the front radius rod bushing. the fix is to replace the front radius rod bushing with a firm urethane bushing like the Pedders EP9166. The other advantage using this bushing is your ability to get an addition 1.25 degrees caster. More on this later. The Pedders EP9019 inner radius rod bushing will add serious support for reducing caster and toe change, and reducing tire wear. There are other benefits that will be discussed later
3.NOISES. There have been a number of noise issues found on the GTO. Here is a list of things that I have seen at least 10 times or more:
a. Front coil contact on parking lot manuevers creating a clicking noise. The repair to this is to reverse the OEM coils. There is a bulletin on this
b. Sway bar end link bushings and links get torn and bent easily. end links bend very easily with aftermarket sway bars. Replacing them with Pedders HD end links is a practical way of fixing this concern. The OEm bushings wear extremely rapidly. If it is just the bushings and the end link is not bent, then the end link bushes can be replaced. Note that the end link washers are dished, and the dish, if you will always goes away from the bushing. This is different than most vehicles.
c. Torn strut bushings, especially when the ferrule delaminates to the bush, can cause a knocking noise, on top of all kinds of other tire wear
d. Strut bearings can get lumpy and create a popping noise
e. 95% of all GTOs on the road that have OEm suspension have damaged front bump stops. They get torn due to excess suspension travel. This can create a knocking noise on a heavy jounce (compression of suspension)
f. Loose tie rod ends. The OEM tie rod ends are very prone to wear and can knock
g. Loose lower control arm bushing nuts and torn lower control arm bushings can easily cause a knocking or clicking type noise in the front
h. Front tires contacting the inner fender wells, especially the right front. You can either remove the portion of the inner fender well, or drill a couple of holes and use a large nylon tie strap and pull the fenderwell forward
4. RIDE HEIGHT CONCERNS. it is normal to have the front end 10 to 15mm low. This is primarily a function of collapsed and damaged strut bushings, and collapsing, under-sprung coils. Our Pedders coils are designed for performance and still maintain a very fine ride quality. Our coils, on average, have a 50% increase in sprung weight. Plus each is bench tested to 2MM tolerance. Also the GTO is a old body design and the acceptable tolerances of the body are significant. It is not uncommon to have as much as 1/2 inch height variation in the body totally due to the assembly and tolerance variations in the body. 5mm variations are more common and there is little you can do unless you have adjustable coil overs
5. BRAKING ISSUES. With the exception of the 2004 brakes, the 05-06 work pretty well, However, there seems to be a detectable lag time in the brake application. To understand the solution, you need to understand the cause. When you jam on the brakes, if there is any looseness or softness in the suspension. Before you actually stop, the looseness must be absorbed first. This is primarily an excessively loose or soft bushing concern. Replacing the radius rod bushings seriously reduces the fore/aft suspension travel, thus causing the brakes to react faster. Also the coils are way too soft. Jam on the brakes hard, the front suspension collapses and the rear suspension grows, this reduces the effectiveness of the rear brakes and adds additional weight and stress to the front brakes, Adding upgraded coils and dampers seriously reduces this affect
6. EXCESS SUSPENSION TRAVEL. This is a function of collapsed and damaged coils, and weak shocks, especially the front oil only struts. Going with a Pedders coil and any one of the 6 or so damper options that Pedders offers will control this concern. The rear is the biggest concern. Watch a OEM GTO take off. Notice how the back end collapses, this also seriously increases negative camber, thus promoting tire wear as well as other negative handling issues.
One of the other issues with excess suspension travel is movement of the strut bushing, even on a new one. A great way to improve the control of the strut bushing is to install a Pedders strut tower brace.. Putting on th animal strut tower brace, I feel, does little but improve "impression ratio". He with the biggest, baddest strut tower brace wins" to be honest the OEM unit works just fine. So how why is the Pedders unit special and different? Pick up your GTO and look at the strut plate to see what it does, It moves down approximately 1/4 to 1/2 inch depending on the condition of the strut bush. Our Pedders strut tower brace eliminate this movement by the positioning of the mounting plate. It goes between the strut mount plate and the inner fender well. Thus eliminating the gap, and eliminating the movement. This makes the spring/strut more responsive and adds life to the strut mount bushing.
7. EXCESS BODY ROLE. Once shocks and coils and critical bushes are updated the sway bars are still under-rated. Now by replacing the sway bar end link bushes, and mounting bushes with our Pedders urethane bushes, will add approximately 10-15% improvements to the OEM controls. This is due to the poly bushes being more responsive. But also Pedders offers a very HD front and rear multi adjustable sway bar assembly that comes with HD end links and rear end link bushes. No other sway bar kit, like Hotchkis, comes with these components. The Pedders HD sway bar kit will offer more control improvement than all the other sway bar kits on the market
8. INSUFFICIENT NEGATIVE FRONT CAMBERS. This is a function of not having sufficient tire clearances and tires being very close to the strut. There are several ways to resolve or reduce this concern. One is to install our soon to be available eXtreme Xa Monotube 30 way adjustable coil overs, install upper strut adjustable mount bushings, or relocate the lower control arm, decrease wheel offsets. Pedders has tested and elected not to have an adjustable strut mount bushing due to what they feel is serious reliability issues especially in the strut upper shock seal. There is a serious increase in strut seal leakages due to this style of strut mount. Pedders has come up with an adjustable lower control arm bushing, that can add approximately .75 to 1 degree of additional negative camber without getting the tire any closer to the strut. Changes in offset wheels really add a lot of strut to tire clearances. There are very few wheels actually made for the GTO. Most are designed for a BMW, and relabeled for a GTO.
9. POOR STRAIGHT LINE STABILITY. There is lots of looseness in the OEM front end, but eliminating the looseness, and increasing spring and damping rates is not enough. Increasing caster is required. Installing the Pedders EP9166 front radius rod bushing not only seriously reduces the caster/toe change by keeping the tire from kicking back to the rear, but it also allows you to add up to 1.25 degrees of positive caster. You can get the front caster to the 10.5 to 11.5 range. The GTO can handle this without any negative affects, as long as your power steering is functioning. Adding caster seriously adds straight line stability and adds steering feel to the driver.
10. LOOSE STEERING FEEL. Once all the excess looseness is eliminated by bushings, springs/dampers, and making sure the tie rods are OK, which are a real pattern failing component, the steering can still feel loose, slow, and lacking feel. Adding front caster improves the feel, but may not be enough for all performance drivers. The OEM gear has a 3 turn lock to lock ratio for the GTO. The Z06 has a 2.6 turn ratio. Pedders offers a very limited supply fast ratio steering gear that has a 2.4 turning ratio. That is more than a 1/2 turn difference from the OEM gear. This also gives you substantial feel improvements, It is most noticeable during aggressive mountain type driving. It feels really great
11. FRONT END NOT CENTERED TO THE BODY. The Monaro in Au requires a front and rear cradle alignment process and supply their Holden dealers with alignment fixtures. In the USA for the GTO, Pontiac only supplies its dealers with a rear cradle alignment tool and does not supply, like Holden, a front alignment tool. Pedders dealers are the only ones that have a front cradle tool. Pedders dealers also align the trans mount to have all 3 cradles perfectly in line
Most of the parts and problems described above, especially strut bushings, can be viewed by checking out my webshots site listed below
Hope this gives all of you some room for thought and explanation of why your GTO is the way it is.
last year, I posted a similiar post that defines the concerns of the GTO suspension and offered solution to the concerns. i was asked to do this by moderators. Somehow, an error occured, and one of the moderators deleted the post. I spent a serious amount of time on this and left this forum. Today I decided to visit the forum again because Rob at Wretched Motorsports is a Pedders sponsor here. So i decided to revisit and will repost an updated definition/solution base for the GTO. Wretched Motors can offer you support to resolve any issues listed below. If allowed I will assist you as well.
I am well known in the GTO community and go by DMS, which stands for "Doing Mike's ****" I have dedicated a very serious amount of time, energy and conflict on the GTO and will pass on knowledge that I have on it. This forum has very little information on the GTO, and I feel this community can benefit by this info, just if it generates questions. So here we go!
The Definitive Explanation of GTO Suspension Concerns and Permanent Resolution Part One
This document was prepared to give the novice GTO owner a list of concerns common to the GTO suspension, and offer solutions to each problem.
FRONT SUSPENSION ISSUES
1. STRUT RUB
2. INSIDE TIRE WEAR AND CUPPING
3. NOISES
4. RIDE HEIGHT CONCERNS
5. BRAKING ISSUES
6 EXCESS SUSPENSION TRAVEL
7. EXCESS BODY ROLE
8. INSUFFICIENT NEGATIVE FRONT CAMBERS
9. POOR STRAIGHT LINE STABILITY
10. LOOSE STEERING FEEL
11. FRONT END NOT CENTERED TO THE BODY
REAR SUSPENSION ISSUES
1. INNER TIRE WEAR AND CUPPING
2. RIDE HEIGHT CONCERNS
3. POOR LAUNCHING AND EXCESS SUSPENSION TRAVEL
4. EXCESS WHEEL HOP
5. EXCESS TOE AND CAMBER CHANGE
6. EXCESS LATERAL SUSPENSION MOVEMENT
FRONT SUSPENSION SOLUTIONS
1. STRUT RUB. There are 2 kinds of strut rub on the GTO. When the GTO first came out, it was common to have strut rub, (tire to strut contact). In 2004 and early 2005, this was due to aggressive alignment settings for negative camber. Why was this a issue in the USA and not in Australia? Simple. GM added approximately 400lbs of structural support to the GTO so it would meed Federal criteria. Due to this, GM needed a larger capacity tire than the 235/45R17 used in Au. To try and increase tire life, GM went to a 245/45R17 tire which has a larger capacity rating, but is 10mm wider. The 235 has a load range of 1433lbs @ 44psi, and the 245 has a load range of 1521 @ 44psiWe initially saw strut to tire contact at the first rotation. GM was/is aware of this problem since the beginning but did not publish anything. If you called GM Technical assistance, they would tell you to put the front cambers to the positive end of specs, .2 camber. This strut rub would only cause a cosmetic issue, and is/was not destructive. This fixes the first style of strut contact, but severely reduced the handling. We have come up with a general spec to go negative on the cambers to the -.3 to -.4 range. At this range, you should be able to have at least a pencil width clearance between the tire and the strut. With that said, it is also CRITICAL to have your tire pressures at 35psi cold!!!. This fixes the first kind of strut rub, at least temporarily.
How many of you had not issues at at at the first tire rotation at 6,000 miles and the second one at 12,000 miles, but at the 3rd rotation at 18,000 miles the inner tire tread is destroyed, and there was evidence of strut to tire contact? You took it to the dealer and they said you must have hit something and knocked the front end out of alignment? Does this ring a bell to many of you?? Now i is true that you could have wacked something and knocked the front end out of alignment. But you also could have driven the GTO like a little old gramma going to Sunday school, and never hit a leaf in the road, and will still have the problem. Why? The strut bushing is damaged the moment it gets off the boat. To protect the front end, Holden installed front coil spacers to eliminate all front coil movement. Then they chained and cinched the car down really tight. The GTO was this way for over a month. This collapses the front strut bushing. But collapsing strut bushings is just the first issue, and by itself, is not that severe of a problem. But when collapsed, it weakens the rubber, and therefore the center of the bushing cannot stay centered in the bushing. This causes 2 issues. First it causes the strut shaft to migrate to towards the engine compartment, seriously increasing negative camber, as well as it will cause the camber to seriously change. The center of the strut bush, thus the strut shaft, will move all over the place, causing serious camber change, which ultimately causes serious toe change, which always screws up your tires.
Now for some controversy: When the strut shaft moves in and out with respect to the engine, this movement is rapid. It will also cause the tires to have excess sidewall flex. Add the normal sidewall flex of turning, and you now have a lot of sidewall movement: enough sidewall movement to cause the tires to kiss the strut. I have seen and documented a severely worn strut bush, causing major inner tire wear, and strut contact, with 1/2 inch clearance from the strut to the tire. The strut contact issue, however, is again primarily cosmetic and not destructive. The tire wearm however, is severe and is often interpreted as contact wear from the strut
So the primary fix will be to replace the strut bush, and bearing, which will most likely come apart once the strut is dissassembled, then re-align the front end to get -.3 to -.4 negative camber. This usually will give you the pencil thickness clearance.
All of us have seen the reallllllly serious strut rub that destroys tires. It is my opinion that this strut rub is only caused by major impacts and bent parts.
2. INSIDE TIRE WEAR AND CUPPING. The primary reason for inside tire wear is wear as a direct result of the strut bushing as previously mentioned. But there is another concern. You can see it by drivng your GTO 7-8mph then seriously jam on the brakes on. Observe the front wheels. It is not uncommon to see the front wheels kick back 2 inches. What this movement does is reduce braking action and brake pedal feel, but mostly causes major caster change, which again causes toe change. Toe gets toed out a lot. This again causes major tire wear, primarily on the inside and is a major contributor to tire cupping, which again is a major problem with the GTO. The cause of the excess movement is primarily the front OEM radius rod bushings that are fluid filled and often leaks, thus increasing the movement. The rear radius rod bushing also gets damaged and the washers bent due to the excess movement caused by the front radius rod bushing. the fix is to replace the front radius rod bushing with a firm urethane bushing like the Pedders EP9166. The other advantage using this bushing is your ability to get an addition 1.25 degrees caster. More on this later. The Pedders EP9019 inner radius rod bushing will add serious support for reducing caster and toe change, and reducing tire wear. There are other benefits that will be discussed later
3.NOISES. There have been a number of noise issues found on the GTO. Here is a list of things that I have seen at least 10 times or more:
a. Front coil contact on parking lot manuevers creating a clicking noise. The repair to this is to reverse the OEM coils. There is a bulletin on this
b. Sway bar end link bushings and links get torn and bent easily. end links bend very easily with aftermarket sway bars. Replacing them with Pedders HD end links is a practical way of fixing this concern. The OEm bushings wear extremely rapidly. If it is just the bushings and the end link is not bent, then the end link bushes can be replaced. Note that the end link washers are dished, and the dish, if you will always goes away from the bushing. This is different than most vehicles.
c. Torn strut bushings, especially when the ferrule delaminates to the bush, can cause a knocking noise, on top of all kinds of other tire wear
d. Strut bearings can get lumpy and create a popping noise
e. 95% of all GTOs on the road that have OEm suspension have damaged front bump stops. They get torn due to excess suspension travel. This can create a knocking noise on a heavy jounce (compression of suspension)
f. Loose tie rod ends. The OEM tie rod ends are very prone to wear and can knock
g. Loose lower control arm bushing nuts and torn lower control arm bushings can easily cause a knocking or clicking type noise in the front
h. Front tires contacting the inner fender wells, especially the right front. You can either remove the portion of the inner fender well, or drill a couple of holes and use a large nylon tie strap and pull the fenderwell forward
4. RIDE HEIGHT CONCERNS. it is normal to have the front end 10 to 15mm low. This is primarily a function of collapsed and damaged strut bushings, and collapsing, under-sprung coils. Our Pedders coils are designed for performance and still maintain a very fine ride quality. Our coils, on average, have a 50% increase in sprung weight. Plus each is bench tested to 2MM tolerance. Also the GTO is a old body design and the acceptable tolerances of the body are significant. It is not uncommon to have as much as 1/2 inch height variation in the body totally due to the assembly and tolerance variations in the body. 5mm variations are more common and there is little you can do unless you have adjustable coil overs
5. BRAKING ISSUES. With the exception of the 2004 brakes, the 05-06 work pretty well, However, there seems to be a detectable lag time in the brake application. To understand the solution, you need to understand the cause. When you jam on the brakes, if there is any looseness or softness in the suspension. Before you actually stop, the looseness must be absorbed first. This is primarily an excessively loose or soft bushing concern. Replacing the radius rod bushings seriously reduces the fore/aft suspension travel, thus causing the brakes to react faster. Also the coils are way too soft. Jam on the brakes hard, the front suspension collapses and the rear suspension grows, this reduces the effectiveness of the rear brakes and adds additional weight and stress to the front brakes, Adding upgraded coils and dampers seriously reduces this affect
6. EXCESS SUSPENSION TRAVEL. This is a function of collapsed and damaged coils, and weak shocks, especially the front oil only struts. Going with a Pedders coil and any one of the 6 or so damper options that Pedders offers will control this concern. The rear is the biggest concern. Watch a OEM GTO take off. Notice how the back end collapses, this also seriously increases negative camber, thus promoting tire wear as well as other negative handling issues.
One of the other issues with excess suspension travel is movement of the strut bushing, even on a new one. A great way to improve the control of the strut bushing is to install a Pedders strut tower brace.. Putting on th animal strut tower brace, I feel, does little but improve "impression ratio". He with the biggest, baddest strut tower brace wins" to be honest the OEM unit works just fine. So how why is the Pedders unit special and different? Pick up your GTO and look at the strut plate to see what it does, It moves down approximately 1/4 to 1/2 inch depending on the condition of the strut bush. Our Pedders strut tower brace eliminate this movement by the positioning of the mounting plate. It goes between the strut mount plate and the inner fender well. Thus eliminating the gap, and eliminating the movement. This makes the spring/strut more responsive and adds life to the strut mount bushing.
7. EXCESS BODY ROLE. Once shocks and coils and critical bushes are updated the sway bars are still under-rated. Now by replacing the sway bar end link bushes, and mounting bushes with our Pedders urethane bushes, will add approximately 10-15% improvements to the OEM controls. This is due to the poly bushes being more responsive. But also Pedders offers a very HD front and rear multi adjustable sway bar assembly that comes with HD end links and rear end link bushes. No other sway bar kit, like Hotchkis, comes with these components. The Pedders HD sway bar kit will offer more control improvement than all the other sway bar kits on the market
8. INSUFFICIENT NEGATIVE FRONT CAMBERS. This is a function of not having sufficient tire clearances and tires being very close to the strut. There are several ways to resolve or reduce this concern. One is to install our soon to be available eXtreme Xa Monotube 30 way adjustable coil overs, install upper strut adjustable mount bushings, or relocate the lower control arm, decrease wheel offsets. Pedders has tested and elected not to have an adjustable strut mount bushing due to what they feel is serious reliability issues especially in the strut upper shock seal. There is a serious increase in strut seal leakages due to this style of strut mount. Pedders has come up with an adjustable lower control arm bushing, that can add approximately .75 to 1 degree of additional negative camber without getting the tire any closer to the strut. Changes in offset wheels really add a lot of strut to tire clearances. There are very few wheels actually made for the GTO. Most are designed for a BMW, and relabeled for a GTO.
9. POOR STRAIGHT LINE STABILITY. There is lots of looseness in the OEM front end, but eliminating the looseness, and increasing spring and damping rates is not enough. Increasing caster is required. Installing the Pedders EP9166 front radius rod bushing not only seriously reduces the caster/toe change by keeping the tire from kicking back to the rear, but it also allows you to add up to 1.25 degrees of positive caster. You can get the front caster to the 10.5 to 11.5 range. The GTO can handle this without any negative affects, as long as your power steering is functioning. Adding caster seriously adds straight line stability and adds steering feel to the driver.
10. LOOSE STEERING FEEL. Once all the excess looseness is eliminated by bushings, springs/dampers, and making sure the tie rods are OK, which are a real pattern failing component, the steering can still feel loose, slow, and lacking feel. Adding front caster improves the feel, but may not be enough for all performance drivers. The OEM gear has a 3 turn lock to lock ratio for the GTO. The Z06 has a 2.6 turn ratio. Pedders offers a very limited supply fast ratio steering gear that has a 2.4 turning ratio. That is more than a 1/2 turn difference from the OEM gear. This also gives you substantial feel improvements, It is most noticeable during aggressive mountain type driving. It feels really great
11. FRONT END NOT CENTERED TO THE BODY. The Monaro in Au requires a front and rear cradle alignment process and supply their Holden dealers with alignment fixtures. In the USA for the GTO, Pontiac only supplies its dealers with a rear cradle alignment tool and does not supply, like Holden, a front alignment tool. Pedders dealers are the only ones that have a front cradle tool. Pedders dealers also align the trans mount to have all 3 cradles perfectly in line
Most of the parts and problems described above, especially strut bushings, can be viewed by checking out my webshots site listed below
Hope this gives all of you some room for thought and explanation of why your GTO is the way it is.