Wheel Alignment.

[EFLImpudence]

OK, so that doesn't look too bad to me at all. If I'm reading it correctly, (and assuming the sign convention is the same in the country it came from as it is here), toe-in is positive and toe-out is negative. So you're looking for a total front toe-in of 1.1mm, give-or-take 0.5mm, which means a total toe-in between 0.6 and 1.6mm. Your "finished value" has a total toe-in of 0.5mm so it could do with an absolute smidgen more toe-in. Frankly, I wouldn't expect to be able to feel that if I were to drive it. Your front tracking is set a bit closer to parallel than specified, so I guess the tyre wear will be minimised, but it might feel a bit vague in the straight ahead position?

Ok. It does not feel perfect but not too bad; it tends to pull in the direction of the road camber either way - obviously nearly always to the right here.

The next row, just shows the figures "per side" - which, perhaps unsurprisingly, should be equal. In practice, of course, to go straight, you'll just end up tuning the wheel until they ARE equal.

Agreed but surely it denotes poor workmanship.

You have 9 minutes of a degree more positive camber on the right than on the left. Is it a left hand drive car, by any chance? It's unusual to see a car with positive camber (wheel leaning outwards at the top when viewed from the front), but if that's what they specify, then fair enough. On most suspension geometries, it goes more negative as the wheel moves up on its spring, so it's possible that the left hand side is sat fractionally lower than the right? In any case, camber might not be adjustable on that car? You can see that the specification is for anything between half a degree positive and half a degree negative, so it's within spec. Likewise, caster and kingpin inclination (which is just as well, because they're unlikely to be adjustable).

Yes, it is left hand drive.

Your rear toe, is worrying though. You're running a LOT more toe-in at the back than specified. Did they not say something about that?!

I have only just bought the car and found the details in the documents.
I had not paid much attention to the rear.

I suppose the document could be a red herring and things have been altered since. I was just unhappy with the position of the steering wheel.

Your total toe-in at the back, should be just less than a millimetre, (0.9mm +/- 0.5mm) and it's actually nearer 3mm! If it were my car, I'd start trying to sort the rear toe before I did anything else. I'm not familiar with the rear suspension on a mid 1990s Previa, but is it semi-trailing arms? Sometimes, they have "snail cam" bolts that can be slackened off and rotated so that they twist the arm on its rubbers to face more inwards or outwards to change the toe. Make sure that the rubber bushes in the arms aren't worn out, before you do anything else, because otherwise, you'll be wasting your time trying to set the toe.

Not sure. I thought it had a live rear axle. Getting confused now.

I think that's where I would start if it was my car. Sort the rear toe and then see where the steering wheel sits. If it's still crooked, a small tweak on the front toe-settings should sort it.

Ok.

I will have a look tomorrow.

 

[DiyNutJob]

I suppose the document could be a red herring and things have been altered since. I was just unhappy with the position of the steering wheel.

Get it fixed at laser shop. It will pay for itself in 30 minutes. Ask them to give you a report of before and after. Then you will be better placed to make a judgement on the red herring. The wonky steering wheel is most likely to do with suspension work done before they sold the car to you. This means they didn't bother to align it.

 

[Avocet]

In the past, as an experiment, I've driven to three different (large national chain) outlets who were offering free wheel alignment checks, and asked them to check but not adjust. Disappointingly, all three gave me different figures for the same car, on the same day...

...which is why I prefer to do my own...

 

[DiyNutJob]

...which is why I prefer to do my own...

This certainly explains why your investment took a whole year to pay for itself. I suspect it's to do with the non-flat ground you thought was flat.

 

[Avocet]

This certainly explains why your investment took a whole year to pay for itself. I suspect it's to do with the non-flat ground you thought was flat.

Indeed, but as someone who has designed vehicle suspension components in the past, and spent several years working as a development engineer for a sportscar company, I hope you'll understand that I don't place a great deal of credence on your views on the matter?

 

[DiyNutJob]

Indeed, but as someone who has designed vehicle suspension components in the past, and spent several years working as a development engineer for a sportscar company, I hope you'll understand that I don't place a great deal of credence on your views on the matter?

You may have all that, and able to quote from text books. But, you just don't have the "feel" for it. If I were to do a test drive on your self-aligned car, doing one lap round the block. I would probably come back and tell you your steering precision is loose like that proverbial thing in a bucket.

 

[Avocet]

You may have all that, and able to quote from text books. But, you just don't have the "feel" for it. If I were to do a test drive on your self-aligned car, doing one lap round the block. I would probably come back and tell you your steering precision is loose like that proverbial thing in a bucket.

I expect your phone is practically melting with all the calls from McLaren and Ferrari, wanting you to come and sort their cars out before each F1 meet...

 

[EFLImpudence]

Not sure. I thought it had a live rear axle. Getting confused now.

Nope. Not a live rear axle.

The online manuals do not seem to be very accurate.

 

[Avocet]

Nope. Not a live rear axle.

The online manuals do not seem to be very accurate.

Can you post up some photos of the rear suspension? Also, is yours definitely a Previa? (I think the same vehicle was sold elsewhere in the world as the "Estima"?

 

[EFLImpudence]

Can you post up some photos of the rear suspension?

Yes, will do but it looks like this.

Definitely had the lower offset washers (toe) and presumably the top ones (camber) too but did not notice when I lookeed.

Also, is yours definitely a Previa?

Yes. TCR11L-RRSGKW

(I think the same vehicle was sold elsewhere in the world as the "Estima"?

It was. A slightly shorter and narrower version for Japanese tax rules.

I used to have an Estima Emina - not generally marketed in UK but specially imported; and no left hand drive option.

 

[Avocet]

Yes, will do but it looks like this.

View attachment 280183

Definitely had the lower offset washers (toe) and presumably the top ones (camber) too but did not notice when I lookeed.


Yes. TCR11L-RRSGKW


It was. A slightly shorter and narrower version for Japanese tax rules.

I used to have an Estima Emina - not generally marketed in UK but specially imported; and no left hand drive option.

OK, it looks like 48409 might be one of those "snail cam" bolts that I mentioned, and I think that will be for adjusting the toe. There looks like there might be another one right at the top for camber. I can't make out the part number.

No photos needed. That's good enough!

 

[Millwright]

I use one of these, and have been very pleased with it:

Trackace Laser Wheel Alignment Gauge

The Trackace Laser Wheel Alignment Gauge is the World's first auto-calibrating, laser accurate tracking gauge, designed for home use and simple storage. Suitable for use with wheels ranging in size from 10” to 22” and accurate to 1' (0.0166 decimal degree), it gives fast, very accurate readings...

www.demon-tweeks.com

It paid for itself in the first year I had it.

However, it does have a number of limitations. It can only measure total toe, so it's fine for front wheels, but can't really be used for rear wheels. It's also quite labour-intensive to set up each time. Typically, I will check, make an adjustment, driver the car round the block, coming to a gentle stop rolling forward and with minimal braking, and then set up again and re-measure. I might have to do that 2 or three times before I get it right, so it takes a good while. Also, make sure it is set up with the laser on the side of the car that is specified in the instructions. If you put it on the other side, it works, but you need to reverse the scales (i.e. toe-in becomes toe-out and vice versa)! Obviously, level ground is important too.
In general, I don't trust run-of-the-mill laser alignment places. Some will be fine, but others, not so much. Places that set up racing cars are more expensive, but generally know how to use the equipment a bit better.

I've got one of those, never gave the same results twice, so put it back in its box and haven't touched it since, for some reason I couldn't make any sense out of it. My friend has a better one which I use instead, his one uses equipment which fits to both wheels, rather than the one which this does, so his gives the same results each time you reset up again.

 

[Avocet]

That's strange? One of the first things I did when I got it, was set it up and then take it off and set it up again three times consecutively, without moving the car. I found it very repeatable indeed. The readings only varied by a couple of minutes each time, and to be honest, the laser "spot" is actually quite diffuse, so it's hard to read the thing with certainty to within a couple of minutes of a degree. My only real criticism, is that it takes longer to set up than other gauges. I'd love a simple, old set of Dunlop optical gauges, but they're too much money and take up a fair bit of space.

 

[Millwright]

I think my problem with it and why I don't understand it, is that the board with the minutes and degrees on it, doesn't fit to the other wheel, so how can it know where the toe is? My friends kit fits to both wheels, so there is a physical connection to each wheel.

 

[DiyNutJob]

I think my problem with it and why I don't understand it, is that the board with the minutes and degrees on it, doesn't fit to the other wheel, so how can it know where the toe is? My friends kit fits to both wheels, so there is a physical connection to each wheel.

The front wheels are connected by the steering rack. The toe at each wheel is modified by the suspension height at that wheel. Unless you have perfectly flat ground, the toes will be all over the place every time the suspension is moved.