Alignment Discrepancies?

Alignment Discrepancies?

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Strudul

Original Poster:

1,585 posts

84 months

Tuesday 16th January 2018
quotequote all
Car was pulling to one side slightly, so had it 4-wheel aligned using a Hunter system. Everything was within spec except one of the camber settings, but only marginally and they aren't adjustable.

Was still pulling to one side, so popped into another shop a couple of weeks later that also uses Hunter for a free alignment check. All the toes are out of spec, but the camber is now fine. rotate

What's going on?
Is my car borked?
Is one of the systems not calibrated correctly?
Do I need to try another shop for a 3rd opinion?

frown


InitialDave

11,851 posts

118 months

Tuesday 16th January 2018
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"In spec" includes tolerances. The tolerance stacking of several aspects being off nominal - but still "in spec" - could have a cumulative effect that's noticeable.

Did they give you actual numbers rather than "it's all green lights on the display"?

The Wookie

13,909 posts

227 months

Tuesday 16th January 2018
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It's not really enough to just have a Hunter unfortunately, a garage needs to keep it calibrated and have someone with more braincells than stubby mechanic fingers to work it properly

If your car is pulling to one side and there's a shop that has shown you a printed sheet showing that the toes are out of spec, I'd tend to believe them!

Strudul

Original Poster:

1,585 posts

84 months

Tuesday 16th January 2018
quotequote all
InitialDave said:
"In spec" includes tolerances. The tolerance stacking of several aspects being off nominal - but still "in spec" - could have a cumulative effect that's noticeable.

Did they give you actual numbers rather than "it's all green lights on the display"?
Yeh, got print outs.

E.g. There's a discrepancy of 7 minutes between the OSF toe values.

Edited: Forgot how to count to 60.

Edited by Strudul on Tuesday 16th January 17:58

DaveCWK

1,978 posts

173 months

Tuesday 16th January 2018
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It could be worn bushes causing the car to sit differently each time, or play in ball joints/steering rack etc.

SonicShadow

2,452 posts

153 months

Tuesday 16th January 2018
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A difference of 7 minutes in toe is quite a bit.

42 minutes is about 0.7 degrees camber, which again isn't a completely insignificant difference.


Strudul

Original Poster:

1,585 posts

84 months

Tuesday 16th January 2018
quotequote all
SonicShadow said:
A difference of 7 minutes in toe is quite a bit.

42 minutes is about 0.7 degrees camber, which again isn't a completely insignificant difference.
Oh wait, 60 minutes in a degree. NSF Camber has only changed 2 minutes. My bad.

OSF caster has changed 39 minutes though.

Toyoda

1,557 posts

99 months

Tuesday 16th January 2018
quotequote all
In my experience most alignment places are hopeless. All the gear no idea.

If you've got the cash just keep trying different places till you get a satisfactory result.

Strudul

Original Poster:

1,585 posts

84 months

Tuesday 16th January 2018
quotequote all
Toyoda said:
In my experience most alignment places are hopeless. All the gear no idea.

If you've got the cash just keep trying different places till you get a satisfactory result.
How can they do it wrong though? The Hunter system gives on-screen step-by-step instructions on how to set it up (rolling it forward, turning wheel etc).




Jaguar steve

9,232 posts

209 months

Tuesday 16th January 2018
quotequote all
Strudul said:
Toyoda said:
In my experience most alignment places are hopeless. All the gear no idea.

If you've got the cash just keep trying different places till you get a satisfactory result.
How can they do it wrong though? The Hunter system gives on-screen step-by-step instructions on how to set it up (rolling it forward, turning wheel etc).
Alignment is done with the vehicle static and doesn't account for changes in dynamic loading from acceleration braking or cornering. If there's any excess movement outside of the manufacturers tolerances on any suspension components under dynamic load then it's quite possible to set up to achieve a sea of green on the print out with the car standing still on the ramp but actually on the road geometry may still be out or drift in and out of tolerance as suspension load changes.

I'd go right through all front and rear bushes, links and ball joints with a pry bar looking for any anomalies or weaknesses before I'd spend any more on alignment. Tyre wear patterns will often give clues as to what's not right.



Strudul

Original Poster:

1,585 posts

84 months

Tuesday 16th January 2018
quotequote all
Jaguar steve said:
Alignment is done with the vehicle static and doesn't account for changes in dynamic loading from acceleration braking or cornering. If there's any excess movement outside of the manufacturers tolerances on any suspension components under dynamic load then it's quite possible to set up to achieve a sea of green on the print out with the car standing still on the ramp but actually on the road geometry may still be out or drift in and out of tolerance as suspension load changes.

I'd go right through all front and rear bushes, links and ball joints with a pry bar looking for any anomalies or weaknesses before I'd spend any more on alignment. Tyre wear patterns will often give clues as to what's not right.
But that doesn't explain why one Hunter system says my alignment is fine and another says all my toes settings are wrong. frown

Jaguar steve

9,232 posts

209 months

Wednesday 17th January 2018
quotequote all
Strudul said:
Jaguar steve said:
Alignment is done with the vehicle static and doesn't account for changes in dynamic loading from acceleration braking or cornering. If there's any excess movement outside of the manufacturers tolerances on any suspension components under dynamic load then it's quite possible to set up to achieve a sea of green on the print out with the car standing still on the ramp but actually on the road geometry may still be out or drift in and out of tolerance as suspension load changes.

I'd go right through all front and rear bushes, links and ball joints with a pry bar looking for any anomalies or weaknesses before I'd spend any more on alignment. Tyre wear patterns will often give clues as to what's not right.
But that doesn't explain why one Hunter system says my alignment is fine and another says all my toes settings are wrong. frown
It might do if your toe is varying between checks because of something like weak wishbone or TCA arm or strut top bushes for example.. It's a tricky one to resolve as you potentially have two problems.- either its a random variation on your car or a random variation between Hunter machines or possibly even a combination of both.

I'd still have a good poke about the suspension to see if you can spot anything obviously wrong.

Ninja59

3,691 posts

111 months

Wednesday 17th January 2018
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Something like an MX5 according to a dealer can be within "specification", but still drive like a bag of crap (or downright dangerously). When I first got my MK3.5 NC the car was "technically" within Mazda specification. But, what concerned me was on the odd occasion in the damp the back would step out without much warning.

Eventually took it to Blink Motorsport, they shoved it on their Hunter (a well looked after one no less) and set it up. The car was a different beast after far easier to drive and none of the back stepping out happened ever again. Downside it set me on a path of having it lowered and quite a bit of other suspension work.

They did 640D last year as well which changed it completely and made it far more enjoyable to drive.

But yes regarding bushes etc. then a Hunter or any alignment tool necessarily won't give that information and that is down to the person doing the alignment to look properly and also so is the above.

Strudul

Original Poster:

1,585 posts

84 months

Wednesday 17th January 2018
quotequote all
Righto, got a service due so will give them all a check then.

996TT02

3,308 posts

139 months

Wednesday 17th January 2018
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Pulling to one side is not generally a symptom of bad toe settings. Look at why camber is out, as others have said, possibly some worn rubber bush, bent wishbone, or the like.

Maybe your next port of call should be an MOT tester so the wheels can be put on shaker plates to check for any movement, if none then something is bent.

curlie467

7,650 posts

200 months

Wednesday 17th January 2018
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I sadly think a lot of garages have a "that'll do" policy.

There's only one garage in the town I live in that I'd bother with for alignment, the rest are crooks and liars in my opinion (5 garages).
Ranging from charging you and not eve putting a spanner on it to knackering stuff.

RedSwede

261 posts

193 months

Wednesday 17th January 2018
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Really, I've never, ever had any problems fixed by a £40 tyre place "alignment". I think I read the phrase "set the toe and let it go" somewhere - and that seems exactly what they do.

This is my understanding - maybe use it as the basis for further research:
-- First, front camber is probably number one for a pull. Front castor could give a small pull, but toe cannot. Toe should ideally be zero when driving - slightly toe in static on RWD, toe out static FWD I believe.
-- Rear toe could cause a pull, but I imagine rear castor/camber would have little effect.

Honestly, as a general rule, if I've had major suspension rework on a regular production car, only main dealers have ever set the car up to drive straight and right afterwards. It might cost 5x more, but it's worth it. There are other specialists knocking around who will do a good job, but it will be in the £100-£200 mark. I've also had a lot of garages say castor or camber cannot be adjusted on a particular car, when it can. And if it really can't, then there are usually eccentric bushes available (cheap, but a pain) or for MacPherson strut, adjustable top plates.

EDIT: As posts above - if the pull has spontaneously occurred without prior suspension work, it has happened because something is worn or damaged. Something needs to be replaced before spending time/money on a good alignment. Alignment doesn't just "drift" out, like these £40 places say...

Edited by RedSwede on Wednesday 17th January 09:33

steveo3002

10,493 posts

173 months

Wednesday 17th January 2018
quotequote all
agree with above 90% of places cant be bothered or dont know any better

readings can be made to go into the green zone by leaning on a tyre while pressing the button , ive seen it done and hade the lies about camber being non adjustable

a decent place will spot worn bushes and suggest theyre replaced before tracking the car

datum77

470 posts

120 months

Wednesday 17th January 2018
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A little trick that we discovered many, many years ago when I was an apprentice mechanic.

Having determined that all the technical specifications were correct - we carried out a little trick that we never had explained or found out why it worked.

Swap the front wheels over - side to side. I would guess that the "pulling" problem was something to do with the tyres. But even if we took the front wheels off and thoroughly inspected both the wheels and tyres, there was no logical explanation as to why it worked - but it often did.

Mr2Mike

20,143 posts

254 months

Wednesday 17th January 2018
quotequote all
steveo3002 said:
agree with above 90% of places cant be bothered or dont know any better

readings can be made to go into the green zone by leaning on a tyre while pressing the button , ive seen it done and hade the lies about camber being non adjustable

a decent place will spot worn bushes and suggest theyre replaced before tracking the car
Totally agree with this.

My local "professional tyre" place has a Hunter machine and the last time I went there with my wife's car to get the toe adjusted (I'd replaced wishbones and dampers and TREs) they showed me the before and after print outs showing how they had needed to adjust the rear camber and toe, and so were charging for a full four wheel alignment. I queried this since the car had a completely nonadjustable rear beam axle, and they were unable to show me the adjustment points. The guy on the desk made some excuse about the technician being confused and adjusted the pricing back to two wheel alignment.

Previously the same BS merchants tried to convince me to buy some horribly overpriced Toyo T1Rs instead of Goodyear Eagle F1s as they were apparently much better tyres. Better for their profit margins...