Previously Wrecked 06 M5, Front caster is out of wack. Any ideas what to do?

My wife's 2006 Mazda5 has a caster issue. We bought it about 6 years ago and It never seamed to have issues with it eating front tires, sway bar bushings and links, until an accident (on the front left side of the car) she had about 30k miles ago. We took it back to the body shop who did the work. Our insurance adjuster called me up and told me the frame is slightly bent, causing the caster to be out of spec on the passenger side. They ruled the damage was preexisting to when we bought/ insured the car with our insurance company 6 years ago. Submitting a new claim is not possible for preexisting damage. So now we can either pay out of pocket to have the car put on the frame rack to try and bend it back within spec or maybe find another solution.

Front caster specs Front Left 2.6, Front Right 1.9.
Front camber specs Front Left -1.1, Front Right -1.4.
Rear camber specs Rear Left -2.0, Rear Right -2.3.

It appears at some point (during one of the many re-alignments) a tech figured out the rear control arms are adjustable and re-adjusted them to factory spec. I believe I had the rear camber closer to -1.0 degrees on both sides.

Anyways, I was thinking about aftermarket caster/ camber plates for the MS3 (if they make them and they fit). If they don't make camber/ caster plates could I use camber plates rotated 90? Any input would be greatly appreciated.
 
Have you taken the car to a well-respected alignment shop? That's the first thing I would do to get their opinion as to what your options are.
 
How bad was the accident (speed of impact and what was broken as a consequence)?

What “frame” (or part of) are you/body shop referring too?

I would suspect bent Lower control arm or more likely a bent front sub-frame before a bent chassis-frame that would require pulling. The LCA and front sub-fames are modular parts that can be swapped for new/used parts for cheap. IMO, if the chassis is twisted, it must have been a REALLY hard impact and I wouldn’t want to own it… The camber plates only adjust camber, hence the name :)
 
I'm curious how the adjuster is determining that the out-of-spec caster is the result of a previous accident?

The LCA and front sub-fames are modular parts that can be swapped for new/used parts for cheap.
I agree, the damage is likely isolated to the control arm or subframe. I'd swap control arm first and check alignment. If unchanged, then get a good used subframe and, when trying to install it, if you can't get it aligned with the body mounting points, then there is chassis damage.

The camber plates only adjust camber, hence the name :)
There are plates that adjust for camber and caster, but not sure if these exist for the 3/5.
 
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Have you taken the car to a well-respected alignment shop? That's the first thing I would do to get their opinion as to what your options are.

Yes, we have taken it to two places and they both show the same values for front caster.

How bad was the accident (speed of impact and what was broken as a consequence)?

What “frame” (or part of) are you/body shop referring too?

I would suspect bent Lower control arm or more likely a bent front sub-frame before a bent chassis-frame that would require pulling. The LCA and front sub-fames are modular parts that can be swapped for new/used parts for cheap. IMO, if the chassis is twisted, it must have been a REALLY hard impact and I wouldn’t want to own it… The camber plates only adjust camber, hence the name

As for the accident that caused the damage, we aren't sure how fast it was going. I guess the car came that way, we put maybe 15k miles on it before another accident involving the drivers side door, wheel and fender. That's why the insurance adjuster is writing it off as being previous damage, because our most recent accident didn't involve the right side of the vehicle.

The guy at the body shop didn't specify what part of the frame was bent since they ruled it as being per-existing damage, they sort of left stopped investigating further than the alignment check. As a courtesy they said they did try to loosen the sub-frame and shift it around to see if they could make any improvements but the measurements seem to be the same as before.

The lower control arms have both been replaced since the original accident. Is it possible the recent accident could have jolted the car enough to bend the right side LCA or front sub frame?

I was hoping to find out if anyone has tried the Speed3 camber plates. I'm having difficulties finding anything that fits the 3/5's.
 
I'm curious how the adjuster is determining that the out-of-spec caster is the result of a previous accident?

They decided it was from a previous accident because the bent side is on the opposite side of the car from our accident. That's why they say its per-existing.


I agree, the damage is likely isolated to the control arm or sub-frame. I'd swap control arm first and check alignment. If unchanged, then get a good used subframe and, when trying to install it, if you can't get it aligned with the body mounting points, then there is chassis damage.

There are plates that adjust for camber and caster, but not sure if these exist for the 3/5.

I'll try installing a new LCA and see how that goes. I'll check for signs of damage to the lower sub frame also. How easy would it be to source a front sub-frame?

I feel like camber/ caster plates wouldn't solve anything if the bend is in the LCA or sub-frame. The caster measurements might improve but the suspension geometry would still be weird. Ideally we would get rid of the vehicle but It doesn't really have any resale value the way it is. I could part it out but I don't really want to do that unless I have to.

I really appreciate all the input you guys are giving!
 
I'll check for signs of damage to the lower sub frame also. How easy would it be to source a front sub-frame?
Hopefully you can spot damage, but I wouldn't count on it. If, say, the control arm mounting point shifted 1/4-inch, it might not be apparent. As far as availability, there has to be a 1st-gen Mz5 that was rear-ended, t-boned, or has a blown engine/transmission sitting in a junkyard somewhere. Call your local (and not-so-local, if need be) junkyards/dismantlers/auto parts recyclers.

I feel like camber/ caster plates wouldn't solve anything if the bend is in the LCA or sub-frame. The caster measurements might improve but the suspension geometry would still be weird.
You're right; caster plates would just be a band-aid, but could result in a car that tracks straight in most situations. It would be the easiest "fix"
 
Ebay has used Mz3 sub frames for cheap, some with free shipping (nobody buys this stuff, which works great for you). It’s a crap shoot, really not much different than a U-pull-it yard. However, you don’t need tools/time/money to pull it yourself or pay someone and it comes to your door. Also, seek a *free* second opinion. Check http://www.hunter.com/gsp9700 to find a local shop. Call and ask who offers a free alignment check (usually the smaller independent shops do). You can get peek at the number and can walk away but they won’t give you the specs sheet.


Is the car drifting or unstable for you? Caster is usually not an issue. See thread below, post 3 for factory specs for a ‘13 (ballpark it for your ’06, if not identical). Look at the caster value and the footnote. Per specs, caster angle tolerance from OEM reference of 2*57’ (or 2.95*) is +/- 1* and left/right difference must not exceed 1*30’ (or 1.5*). What you have appears to be ok concerning cross-caster but the right is at the extreme end of tolerable, out of spec by .05*. Your situation is not ideal but if you are having issue tracking or instability, perhaps have the toe setting looked at.
https://www.mazdas247.com/forum/showthread.php?123839466-What-are-your-alignment-specs


General alignment tech article.
http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=4
 
Ebay has used Mz3 sub frames for cheap, some with free shipping (nobody buys this stuff, which works great for you). Its a crap shoot, really not much different than a U-pull-it yard. However, you dont need tools/time/money to pull it yourself or pay someone and it comes to your door. Also, seek a *free* second opinion. Check http://www.hunter.com/gsp9700 to find a local shop. Call and ask who offers a free alignment check (usually the smaller independent shops do). You can get peek at the number and can walk away but they wont give you the specs sheet.


Is the car drifting or unstable for you? Caster is usually not an issue. See thread below, post 3 for factory specs for a 13 (ballpark it for your 06, if not identical). Look at the caster value and the footnote. Per specs, caster angle tolerance from OEM reference of 2*57 (or 2.95*) is +/- 1* and left/right difference must not exceed 1*30 (or 1.5*). What you have appears to be ok concerning cross-caster but the right is at the extreme end of tolerable, out of spec by .05*. Your situation is not ideal but if you are having issue tracking or instability, perhaps have the toe setting looked at.
https://www.mazdas247.com/forum/showthread.php?123839466-What-are-your-alignment-specs


General alignment tech article.
http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=4

I get what you're saying. I found a MZ3 at the local picknpull, it should be relatively cheap. I found a MZ5 subframe at another junk yard for $200 they pull it. I'm ok with pulling it my self at the picknpull. I assume the MZ3 and 5 subframes are interchangeable? I pulled up a parts diagram and they have different part numbers but look the same.

I appreciate you posting the link to that thread with the factory specs. My car seams to drive ok, it drives straight when coasting and put pulls to the right when accelerating. The more you accelerate the more it pulls. The biggest annoyance with the car is it needs an alignment every 5k miles or so. If we let it go for a while it develops a vibration and pulls all the time, thus balding tires. Also regardless of the alignment, it likes to eat sway bar bushings and links. I guess to sum it up I hate how its always seams to need another alignment, it eats front suspension parts and tires abnormally fast.
 
Hope the LCA or front sub-frame is the problem so you can do a proper fix.


IF it turns out the chassis-frame needs to be pulled for caster, I have a crazy (cheap) thought that may work. The principle is simple - shim it.

Buy two PASSENER side shock tower stiffener plates (driver side plate has bracket welded on and pass. bracket can be inverted to work on both sides). Shave down the Passenger side plate to have a VERY slight incline plane to allow for more caster (and camber too). Since only an ever-so-slight angle is needed (ensure smooth surfaces) should be a doable DIY. The OEM values have a decent amount of play. Just make sure to grind/shave in the right direction (plate position is fixed via the 3 mounting bolts). Or seek out a local machinist to do this but I think if don’t slowly, it can be DIY. The extra plate would go on top of the strut mount before securing to the chassis. The driver side would need to add the other blank plate to even out the Left-Rigth height, which will be slightly higher (1/8”?) than the rear. I think the OE bolts should be able to account for added depth. Worst case, can get longer replacements bolts at a local/online Fastenal store.


Steal pic from Phunky. Add permanent stiffener plate here (with slight angle to gain caster). Need extra plate on other side to account for L-R balance.
cache.php




Disclaimer: This is just a though. Do at your own risk.
 
Caster is not a tire wearing angle. The alignment or frame shop needs to check I.A. (included angle) and S.A.I. (steering axis inclination). These angles will tell you the difference between the front suspension left side and right side wheels when TURNING. These angles will help tell you what is bent. I have also seen cases where every front end part was replaced / subframe replaced and it car STILL pulled or wore tires! If I were you I would try to even up the Caster - make it more positive on the right side than left (a common practice because of road crown) and leave it at that. Don't think it's adjustable (??) but we would sometimes slot the tower plate holes in extreme cases.
 
Hope the LCA or front sub-frame is the problem so you can do a proper fix.


IF it turns out the chassis-frame needs to be pulled for caster, I have a crazy (cheap) thought that may work. The principle is simple - shim it.

Buy two PASSENER side shock tower stiffener plates (driver side plate has bracket welded on and pass. bracket can be inverted to work on both sides). Shave down the Passenger side plate to have a VERY slight incline plane to allow for more caster (and camber too). Since only an ever-so-slight angle is needed (ensure smooth surfaces) should be a doable DIY. The OEM values have a decent amount of play. Just make sure to grind/shave in the right direction (plate position is fixed via the 3 mounting bolts). Or seek out a local machinist to do this but I think if dont slowly, it can be DIY. The extra plate would go on top of the strut mount before securing to the chassis. The driver side would need to add the other blank plate to even out the Left-Rigth height, which will be slightly higher (1/8?) than the rear. I think the OE bolts should be able to account for added depth. Worst case, can get longer replacements bolts at a local/online Fastenal store.

I like your idea of shimming it. I think I might try this first and then the LCA and see what happens. I haven't gotten around to it yet, I've been working on the house lately and I'm having it re-roofed. Its killing my wallet. lol

but we would sometimes slot the tower plate holes in extreme cases.

I've read about slotting the tower holes for extra camber. It's something the Honda Civic guys do when they are on a $25 budget for lowering and stancing their cars. lol But slotting the holes to correct an issue would be something I could live with as a last resort. I'll try shimming first, then slotting if all else fails. The next alignment I get I'll ask them to check the I.A. and the S.A.I. hopefully they are able to do so.


So far all I've had time to do was get under the car and do some measuring. Everything measured out evenly and I saw no signs of bent or stressed/ chipped paint on the subframe or LCA. So no telling if they are bent. I saw the subframe had been shifted around by the alignment shop, in an attempt to correct the issue.

Thank you guys for the input!
 
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Update,

So I found a Mz5 at the local picknpull, It had some sort of engine failure or something. It had no impact damage what so ever so I figured it was safe to assume the K-frame wasn't bent. lol I bought it for $60 and Installed it. I also grabbed those strut tower stiffener plates like Silentnoise713 suggested (in case i needed to make those shims). I didn't have a chance to buy a new LCA but was excited to install the K-frame. So I figured whats could it hurt to go ahead and install it. After a test drive I did notice it drove a little straighter but it was hard to tell. I took it to get it aligned and received these results.

Front caster specs Front Left 2.3, Front Right 2.0.
Front camber specs Front Left -1.0, Front Right -1.2.
Rear camber specs Rear Left -2.3, Rear Right -2.3.

and the old specs

Front caster specs Front Left 2.6, Front Right 1.9.
Front camber specs Front Left -1.1, Front Right -1.4.
Rear camber specs Rear Left -2.0, Rear Right -2.3.


They aren't exactly the same on both sides but they are a lot closer than before. Next I'll throw a LCA at it and see what happens. After getting intimate with the anatomy of the front end I figured I could actually shim the K-frame its self with a very thin washer, I also noticed there is play in the 4 main bolt holes to allow a minor shift of the K-frame (probably to counter imperfections in the manufacturing process or something). I tried to look for damage to the old K-frame and thought the right side arm (the arm thing that sticks up and bolts to the frame rail) looked slightly off but that's just eye balling it. While installing the new K-frame that right side upper bolt was the most difficult to get in without cross threading it. Before torquing the bolts down I made a point to shift the frame straight back and as even as I could get it.

Unfortunately I forgot to ask the shop if they can check the I.A. (included angle) and S.A.I. (steering axis inclination) like CAmz5 suggested. But I will be back in there soon enough to see if anything has changed.

Thank you all for the help you guys!
 
Yet another issue arises. I didn't want to hijack anyone elses thread. The front end of my car seams to be bottoming out now. I've had this issue before and fixed it with a set of new Monroe struts and springs. For some reason the right side strut seams to be worse. The struts on it now have maybe 30k miles on them. When I roll over speed bumps it feels like the passenger side dips more than the drivers side. Its subtle but I can feel it. Any ideas on what could be going on?
 
Yet another issue arises. I didn't want to hijack anyone elses thread. The front end of my car seams to be bottoming out now. I've had this issue before and fixed it with a set of new Monroe struts and springs. For some reason the right side strut seams to be worse. The struts on it now have maybe 30k miles on them. When I roll over speed bumps it feels like the passenger side dips more than the drivers side. Its subtle but I can feel it. Any ideas on what could be going on?

Sounds like a blown strut... but I believe Monroe has a lifetime warranty, so they should replace it free of charge.
 
Wishmaster, I kinda thought that was the issue but was hoping it wouldn't be that because these struts have like 30k miles on them. I didn't know they had a lifetime warranty. I'll look for the warranty info and see what I can do. Thanks for the help!
 
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