Help with my a-arms
Thread Starter
Intermediate
Joined: Sep 2004
Posts: 49
Likes: 0
From: Philadelphia Pa
Help with my a-arms
Hello all.
I am unsure if one of the arms are bent. Posted pics. If someone could comment I would appreciate it. The pass side a-arm has much more spacing at the shock mount compared to the driver side. Is there a way to spec them out to tell if one is bent or if this is correct
Pass side
Driver side
Pass side
Driver side
I am unsure if one of the arms are bent. Posted pics. If someone could comment I would appreciate it. The pass side a-arm has much more spacing at the shock mount compared to the driver side. Is there a way to spec them out to tell if one is bent or if this is correct
Pass side
Driver side
Pass side
Driver side
Le Mans Master
Joined: Jan 2000
Posts: 8,918
Likes: 27
From: New Hill NC
Well there has definitely been some pulling and hammering on the tower supports and the arms. I can see dents and marks, So there is a high probability that something has been done up there. However, that big shim pack is probably the source of most of the difference in the distance from the shock to the arm. You can measure the frame, but a good alignment is about the only way to know what you got.
Pro
Joined: Oct 2005
Posts: 541
Likes: 1
From: Freeport FL
I too wonder about the crease on the inboard edge of each control arm, in the center by the tower support. However, I guarantee what you are looking at is caused by that big shim pack mentioned above. I just rebuilt my front suspension and had this same exact question when looking at mine, and couldn't figure it out until I had someone else look at it also. I know exactly what you are looking at, its amazing that that shim pack can make it look so screwed up, but it does.
The question we each must ask ourselves then, is: Why so many shims? Only an alignment shop can answer it, and I still dont have my new motor in to be able to wheel it over and ask them. But I will
I suspect in the end though, we are going to find out that its not near as serious as we might think.
PS my big stack was on the same side as yours, but on the rear bolt instead of the forward one.
The question we each must ask ourselves then, is: Why so many shims? Only an alignment shop can answer it, and I still dont have my new motor in to be able to wheel it over and ask them. But I will
I suspect in the end though, we are going to find out that its not near as serious as we might think.
PS my big stack was on the same side as yours, but on the rear bolt instead of the forward one.
Team Owner
Joined: Sep 2006
Posts: 31,278
Likes: 4,372
From: Westminster Maryland
The 71 AIM note says that the nominal shim pack is 3- .12" shims, plus a max of 1-.06" and 1-.03" shim. Does this mean that if more than that # of shims are needed it's a frame issue and not just an alignment issue?
Regards,
Alan
Regards,
Alan
Thread Starter
Intermediate
Joined: Sep 2004
Posts: 49
Likes: 0
From: Philadelphia Pa
Thanks for your replys. I am ready to rebuild the front of the car as the back is done. However, I am afraid to put all that effort into the a-arms if they are out of whack. I guess as you have stated it may look worse than it really is.
Do pros have some kind of jig or set of specs that they refer to before they rebuild your a-arms to determine their ability to be reused?
If the a-arms are out of spec will front end alignment resolve the issue? Or is this a crap shoot- do all the work and hope it aligns correctly?
Do pros have some kind of jig or set of specs that they refer to before they rebuild your a-arms to determine their ability to be reused?
If the a-arms are out of spec will front end alignment resolve the issue? Or is this a crap shoot- do all the work and hope it aligns correctly?
Pro
Joined: Oct 2005
Posts: 541
Likes: 1
From: Freeport FL
Thanks for your replys. I am ready to rebuild the front of the car as the back is done. However, I am afraid to put all that effort into the a-arms if they are out of whack. I guess as you have stated it may look worse than it really is.
Do pros have some kind of jig or set of specs that they refer to before they rebuild your a-arms to determine their ability to be reused?
If the a-arms are out of spec will front end alignment resolve the issue? Or is this a crap shoot- do all the work and hope it aligns correctly?
Do pros have some kind of jig or set of specs that they refer to before they rebuild your a-arms to determine their ability to be reused?
If the a-arms are out of spec will front end alignment resolve the issue? Or is this a crap shoot- do all the work and hope it aligns correctly?
Team Owner
Joined: Sep 2006
Posts: 31,278
Likes: 4,372
From: Westminster Maryland
Hi D73,
There are some frame dimensions in the Frame Section of the CHASSIS SERVICE MANUAL. Perhaps you can use them to determine if the front of the frame is tweaked or if it's the A-arms that are bent. Perhaps the A-arms were bent to make up for a bent or twisted frame.
Regards,
Alan
There are some frame dimensions in the Frame Section of the CHASSIS SERVICE MANUAL. Perhaps you can use them to determine if the front of the frame is tweaked or if it's the A-arms that are bent. Perhaps the A-arms were bent to make up for a bent or twisted frame.
Regards,
Alan
Drifting
Joined: Mar 2008
Posts: 1,900
Likes: 3
From: Nixa Missouri
This is just a suggestion but try to contact Dan at Van Steel and see if they have any Ideas about this subject. Dan helped me the other day with a question about my rear end and it was a big relief. May be they can help you out.
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Race Director
Joined: Mar 2006
Posts: 14,112
Likes: 28
From: Florida
99.9% that they are not bent. The marks are just from prying on it for placing shims.
The fronts are aligned from the rear wheels and if the rear is out a little the front will need more shims than usual. There are other reasons but that is the most likely from those pics.
The rear aligments were always a pain even back then and not many mechanics knew how to do them or even bothered to. Unless someone really bitched they sometimes just said they did the rears.
Before taking it in for an alignment, prep the trailing arm shims and bolts so they are free and the bolts loosen and tighten easily. Tell the shop that it is all prepped.
Shop around for an alignment shop with hands on trailing arm experience, few have it.
The fronts are aligned from the rear wheels and if the rear is out a little the front will need more shims than usual. There are other reasons but that is the most likely from those pics.
The rear aligments were always a pain even back then and not many mechanics knew how to do them or even bothered to. Unless someone really bitched they sometimes just said they did the rears.
Before taking it in for an alignment, prep the trailing arm shims and bolts so they are free and the bolts loosen and tighten easily. Tell the shop that it is all prepped.
Shop around for an alignment shop with hands on trailing arm experience, few have it.
Pro
Joined: Oct 2005
Posts: 541
Likes: 1
From: Freeport FL
Advanced
Joined: Jun 2008
Posts: 67
Likes: 0
I've done my fair share of suspension and alignment work however I have never replaced an upper control arm unless the vehicle had been in a severe accident. The lower control arm is more likely to receive damage; such as running over parking blocks and the like Even a sidewall curb hit is going to cause the lower arm to bend because the force is below the centerline of the spindle. The arm is creased because someone was try to pry it.
What would worry me the most is why are there so many shims on the back of the drivers arm. Someone was having a hard time obtaining enough positive caster. This could mean that the lower arm is bent backward; however I would bet that someone was trying to align the vehicle with worn out ball joints and bushings.
Norm
What would worry me the most is why are there so many shims on the back of the drivers arm. Someone was having a hard time obtaining enough positive caster. This could mean that the lower arm is bent backward; however I would bet that someone was trying to align the vehicle with worn out ball joints and bushings.
Norm
Le Mans Master
Joined: Jan 2000
Posts: 8,918
Likes: 27
From: New Hill NC
Oh, its more than that. Look at the hammer marks on the LH tower bkt. and also there are two types of upper shafts, and one is definitely bent. This indicates that someone pulled that front cross member on a machine and hooked up to the towers with the suspension assembled. Thats what bent the shaft. Even with that, It might not be a problem if the alignment can be done to specs.
Cruising
Joined: Jul 2004
Posts: 12
Likes: 0
A Frame/Alignment
On My 75, the rear lower a-frame mount was bent and had broken welds, probably fron a tire/curb misunderstanding.
Check these carefully as the lowers take a lot more guff than the uppers.
Hope this helps
Check these carefully as the lowers take a lot more guff than the uppers.
Hope this helps
Advanced
Joined: Jun 2008
Posts: 67
Likes: 0
Oh, its more than that. Look at the hammer marks on the LH tower bkt. and also there are two types of upper shafts, and one is definitely bent. This indicates that someone pulled that front cross member on a machine and hooked up to the towers with the suspension assembled. Thats what bent the shaft. Even with that, It might not be a problem if the alignment can be done to specs.
Norm
Le Mans Master
Joined: Jan 2000
Posts: 8,918
Likes: 27
From: New Hill NC