Confusion about Front Wheel Alignment Specs

Dear all,

during the last couple of days, I did some research on XJ alignment specs (official Workshop manual, Haynes manuals on XJ6 and XJ12, this forum, etc.). The reason for me doing this is that I had my XJ12 (1983) aligned back in late autumn after doing some maintainance on the front suspension, and the garage managed to align the front suspension in a way that the steering wheel was completely out of center. So, I went to another shop the other day, and they were able to roughly center the steering wheel; but they claimed that front camber was way out of spec on the right side, and that they couldn’t fix it, as they were supposed to remove shims where there are none.

All that raised my suspicion, and I got even more suspicious, when I realised that where the shop mechanic wasn’t able to find any shims to remove, there were actually three of them, adding roughly 7.3mm at the upper wishbone! So, I had my next DIY project, wheter I liked it or not.

To cut the long story short: After some hours of fiddling around, I managed to set front toe to approx. 0mm. Front camber I set to -.3° on the left side, with -.5° on the right side, respectively.

But, what about the specs?

The official Workshop manual claims, with respect to the XJ12, for +.5° +/-.25° front camber and 0-1.6mm toe-out for the front wheels. However, for the XJ6, it states +.5° +/-.25° front camber as well, but 1.6-3.2mm toe-in (!). To make confusion perfect, Jaguar changed the XJ6 specs for front camber to -.5° (!) +/- .25°, and for front toe to 0-3.2mm (!) toe-in in late 1983 (from VN 360146 onwards)! (I skip the specs given by the alignment machines at the shops I visited – they add even more colour to the overall picture.)

I don’t think that all these variations make much of a difference. I decided to go for 0mm front toe, which I think I was able to set-up and which fits all the specs given; and I went for a small amount of neg. chamber, which might provide the car with a slightly better steering in turns. Good news is, the steering has improved significantly, compared to being completely out of any specs before (not to mention the uncentered steering wheel), so I think I will leave it now the way it is.

However, I am still puzzled by the variation of the official specs:

  1. Why are there different numbers given for the XJ6 and the XJ12? Isn’t the front suspension/steering (more or less?) identical, regardless of the engine installed?

  2. What made Jaguar change the XJ6 specs in 1983? If a take a look at the parts catalogues, there was no change whatsoever on the front suspension in 1983 – or do I miss something?

What’s the reason behind all this? I realise that there has been ample discussion on the topic in the forum, but I couldn’t find answers to these two questions. Are there any?


If you want to do something right do it your self they say.
I gave up with alignment shops long time ago…
Alignment specs are a compromise, as with anything in life, and it’s a matter of what suits best.
It’s also the advent of Radial Tyres that changed the geometry and specs required as they behave differently. I always used the latest specs.

How did you measure it?
Here is what I did:

Did you use the ride height tools?
It’s imperative for the rear (info on Kirby’s book) and highly recommended for the front.

Toe-in is a good thing and I suggest you dial some in.

Did you took measurements on the rear wheels? They are as important as the front.

0.2° difference is precise enough and your values in range.
Some deliberately put a bit more camber at the right side to compensate road inclination (on LHD cars) but ideally the should be the same.

You should also measure Castor.

Here are some useful specs and the values I used with good results, i.e. good handling and no tyre wear.

Front: 1480mm - Rear: 1495mm


Camber: -0.5° +/- 0.25°
Castor: +3.5° +/- 0.25°
Toe In: 0 to 3.2mm – 0 to 0.25°

Castor Measurement:
C1+C2 x Z

C1: Camber absolute value at +X°
C2: Camber absolute value at –X°
Z: Angular value constant:
27° = 1.0 (Approx. one full turn of steering wheel)
20° = 1.5
15° = 2.0
10° = 3.0

Car will pull on side with less positive Castor
Car will pull on side with less negative Camber

Camber: -0.75° +/- 0.25°
Toe In: +/- 0.08mm +/- 0.03°

Ride Height
Front 152mm to bottom of Sub Frame - 611mm to centre of Headlights
Rear 162mm to Rear Edge of Wishbone - 189mm +/- 6mm to Sub Frame Differential Plate

Front Ride height Tool:

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Hi Aristides! Thanks a lot! No, I didn’t use ride height tools – both shop provided the same measurements for the rear suspension, both were within specs (toe and camber), so I thought I could skip that one. :slight_smile: But, you are right, I maybe at least should get me a tool for the front alignment and remeasure camber – should have checked the books first! However, I am optimistic that the setting is quite good now, as the car is of equal height on both sides.

The toe measurement I did with two strings along the car, one on each side. I adjusted the strings to the hubs, and took into account the difference between front and rear track, that is: 40mm distance to the front hubs, 32.7mm to the rear hubs. However, when I measured the distance between the strings at the front and at the rear end of the car, I realised that they weren’t parallel. The configuration improved with equal distance to all four hubs (I used 40mm), which means that there isn’t much difference between front and rear track. Any ideas on that? Does this relate to the car being unladen and me not setting the rear end at the correct height by means of JD25B (or equivalent)?

Anyway, I set toe with the strings exactly parallel to the car. Rear toe is negligable on both sides, front toe as said above, more or less 0mm.

You miss something :slight_smile:

Early 6-cylinder cars had different lower control arms versus the V12. Later 6-cylinder cars had the same lower control arms as the V12. Different geometry, different alignment specs. This change was made towards the end of the 1983 model year…although “model year” itself can be confusing. This was done to improve the steering and driving characteristics.

This was discussed at length some years ago. Here’s a summary in chart form:

I might add that, as the years went by, alignment specs changed a couple more times. These changes are shown in Jaguar TSBs. The repair manuals might not show them. This perhaps accounts for the unfamiliar specs provided by the alignment shops; it might be they are using the “TSB” specs rather than the service manual specs.

Or it might be that they are simply wrong.


The absolute necessity of using the height-setting tools has been debated since…forever. I’m in the “you don’t need 'em camp” but it isn’t a hill I choose to die on :slight_smile:

These cars seem to be quite forgiving with respect to alignment settings. And, remember, the specs don’t show a single precise setting but, rather, an acceptable range of settings which will provide a satisfactory result. That said, the difference between satisfactory results and optimal results is not lost on me. For optimal results a person my want to try using the height-setting tools and see what happens.

Personally, I ask the shop to make the adjustments at existing ride height and get as close as possible to 0.5º negative camber, 3.5º positive castor, and 3mm toe-in…which are the specs shown by Aristides. I’ve always been happy with the results on my old Jags.

All of the above “IMO”. :slight_smile:


Thanks, Doug, for the clarification! I’m still confused: They changed the XJ6 front suspension, and after that change it was identical to the XJ12 suspension. However, camber specs were the same for all XJs before that change was made, and they differred afterwards. Isn’t that weired? Or is the reason for this to be seen in the discrepancy between toe-in (XJ6) and toe-out (XJ12)? Which would imply for all later SIII cars: either give them neg. camber and toe-in, or pos. camber and toe-out?

As for the practical aspects, I also think that this setup, which is the same I used (albeit with zero toe-in), works well. I went for a longer drive today, quite happy with it.

  1. Watch the front tires. Any side scuff? A bit of a lip formation denoting it.

  2. At one time alignment shops set the castor a bit different on each wheel as a counter to road crown. Road crown nowadays less pronounced or non existant. Highways and freeways with none. Locals with ess than at one time.

I set the toe on my F150 4x4 by the string method. it worked…

I have a couple of comments, mostly footnotes to DD. And all IMHO.

To get proper alignment AND center the steering wheel, begin by centering the rack within its housing (see archives if you don’t know how it’s done). This ensures that the inner tie rod ends are in the same vertical plane as the lower wishbone inner pivots, minimizing bump steer. Then, adjust the upper steering shaft splines so that the turn signal cams are symmetric left and right. Then adjust the steering wheel splines so that it is centered. Independently, set camber and toe while the rack is still centered. Caster setting last, turning as needed.

I don’t know why they ever specified toe out; I thought that was only for some front wheel drive models.

There was a trend towards negative camber, both front and rear, around this time. Performance trumped tyre wear considerations, and the then-new radial ply tyres benefited especially. Early Jaguars tended to lack alignment range adequate to get specified (or greater) positive caster whilst having enough negative camber. The adjustments interact for reasons beyond my pay grade. People can cheat by setting the front and rear camber shims differently, also beyond my pay grade, and considered not cool. At the time DD mentions, the lower wishbone was changed; the difference was that the lower ball joint, previously centered, was moved in the front-to-back direction to “bias” the caster in the positive direction. This helped to get the proper caster and camber simultaneously. I think it also improved the anti-dive characteristics.

Waaaay back in the day, “toe out” was a toe measurement taken at full lock. But pretty much everyone on the planet just presumed that “toe out” = -“toe in”, to the point that that now is the accepted meaning of the term.

Yes, this was a point of confusion for me as well.
That’s why I used two bars, one in the front and one in the rear that set the strings parallel by default.

I would still dial some toe-in to minimise tyre wear.

I did measurements with and without the ride height tools.
The front gives a very slight increase on negative Camber with the tool, but otherwise, at least in my V12, the actual ride height is very close, the height tool raises the suspension only by a few mm.

On the rear though the difference was much greater, the suspension gets compressed by a couple of cm and there as much as 0.5° difference in rear Camber.
Rear Track also changes slightly as the wishbones are much closer to parallel with the ground.

What surprised me most was that toe ‘out’ was specified, Florian, or at east accepted on the V12.

Toe in is essentially the approved way of keeping the car on a straight line - together with wheel castor. With toe in; deviation from straight will 0 the toe on one wheel reducing its the rolling resistance - the other wheel will have higher rolling resistance - pulling the steering towards straight ahead. With toe out - the opposite occurs; the car feels ‘nervous’. Done deliberately; the steering is more responsive - but requires constant attention to keep the car going straight…

The castor again enhances the straight ahead, but it is also sensitive to road camber; the front tends to 'fall off" downslope - requiring steering inputs to counter veering off course. Sometimes castor angles are deliberately reduced on the kerbside wheel to counter this effect - which is counterproductive on a flat road…:slight_smile:

All alignments are compromises as angles constantly changes with suspension movements. Setting ride heights with appropriate setting tools will increase potential setting precision - bringing the car to the speck ride height. However, overall precision still depends on the setting tools used - and care of the setter…:slight_smile:

The effect of small deviations is not very noticeable, and for special effects; deliberate deviations from spec is not unheard of - though any ‘improvements’ are arguable…

xj6 85 Sov Europe (UK/NZ)

Dear all,

thanks for all the help! In the meantime I set front toe to 1.5mm toe-in (yep, that’s good!) and continued with my measurements.

Caster is low on both sides, was around 2,6°, is now about 2,85° (did a little adjustment), but I can’t set it further to pos. on the right side (all four shims in front of the ball joint), so I’ll leave the left side as well. I think I’ll have to simply accept that.

The same might apply to the following issue: Even though steering significantly improved, it’s still not perfect. That is to say, there is a very slight pull to the right side (no, it’s not because of road camber – did sufficient test driving). The pull is barely noticable, but it is there. I was wondering, could that relate to the fact that rear toe is a little asymmetrical? Shops measured left and right toe to be within specs; however, their measurements show that there is some toe-in on the right side, with the toe being a little negative (toe-out) on the left side. I measured about 0,5mm toe-in on the right side and -0,7mm on the left side of the rear suspension. I know, it’s not much, and it’s nearly within specs; but wouldn’t a little toe-in on the rear right and a little toe-out on the rear left lead to at least some steering to the right hand side of the car?

As I understand it, there is not much I can do about it on the rear suspension. But what about compensating for the rear steering, if this is what I experience, by adding some neg. camber on the front/right?


There are those who advocate a tad more caster on the driver’s side – whichever side that is – to help deal with crowned roads.

More than anything it’s important that Castor and Camber are equal on both sides.

Assuming Toe is correct:
If the steering wheel has a tendency to turn to the right it’s Castor.
Car will pull on side with less positive Castor

If the car just wanders to the right it’s Camber.
Car will pull on side with less negative Camber

Yes it would.

You mean 0,5mm toe-in on the right side and 0,7mm toe-out on the left side?
If this is the case the rear will be puling to the left so the car will be pulling to the right.

This is how I fixed my rear toe issue.
Brutal, but it worked…
Heating and squelching is an other option.

How about rear Camber? Also very important.
Did the shop settle the rear before taking measurements or it just dropped the car?
If the later, all rear measurements are off.

The car will drive straight but plane towards the left, good if there is road camber, bad it the road is flat.

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Just as an aside, I’d recommend swapping tires front-to-rear on both sides just to see if it makes a difference. It’d be a shame to do all this fiddling to get the steering to feel right only to discover it’s all due to the front tires being worn a little wonky by the way the alignment had been set up before.

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So did I, about all they can do is toe in. Many new cars have no facility for other than toe in - this is what “alignment” means now. Shims required for other aspects for us. Have made my own shims, have my own jigs and a have a nice level garage floor. Paul.

Toe ‘in’ on the right and toe ‘out’ on the left will push the rear of the car continuously to the left, Florean. And if the front is biased ‘straight ahead’, subtle ‘left’ steering input is required to go straight - the car is then subtly crabbing sideways.

Compensating for this with front geometry adjustments is virtually impossible?

xj6 85 Sov Europe (UK/NZ)

Guys, just let me say in-between, you are great. I very much appreciate your help, it does help me a lot when working on this car; this forum is just a great place to be – and, if I may say so: just as gentle as the cars we drive.

Now, back to my little woes. The tires it was! Thank you, Kirby, for pointing me to the obvious. I should have checked that earlier – how embarrassing. In German we use to say: Sometimes you won’t see the wood because of all the trees blocking your sight. The pull-thing vanished, at least that’s my impression after a little drive. Will do some more test driving in the days to come (weather is fine, Easter’s coming). Btw, it is no surprise at all that the tire wear is uneven left/right, as front camber was way out of spec, and highly asymmetrical. I should have concluded that!

One more question on caster: If I get it right, the car will pull to the side where caster is less positive. So, less positive caster on the left hand side >> car tends towards the left side. Shouldn’t then the driver’s side have a little less caster in general? The driver, no matter if LHD or RHD car, will always be near the crown, and you would want the car to steer towards the crown to counter the road camber, wouldn’t you? At least, that’s why I set my caster a little lower on the driver’s side (left). I could easily move another shim there, but then I would have a little, little bit more pos. caster there, when compared to the passenger’s side (right). (It’s just impossible to achieve total balance.)

Aristides, thank you especially for your remarks on the rear suspension. I feel that I sould build me a proper tool for a serious rear alignment. Of course, the shops did nothing but put the car on their expensive (as they wouldn’t forget to mention) high-tech stand, so I don’t know how reliable those results are. Without any height adjustment, toe is (as I already stated) a little asymmetrical, and camber as well: -0,41° left, -1,09° right. So, camber is slightly out of spec on both sides (should be between -0,5° and -1,0°), but just by a tiny tad. Don’t know if it’s worth the effort – I should definitely confirm the measurements first by setting the ride height to specs.

Does your car dog track with the rear steering slightly right?

Dog track from front steer unintended as well. .