2 or 4 wheel alignment? - Page 6

BigRuss · 28th October 2018, 10:43

On some it's a full tank depending on model year, or the appropriate weight added to the rear of the boot space or back seats to replicate any missing fuel in the tank

That's why it's essential to get the correct data for your year

Without doing that any adjustment is going to be incorrect, fancy alignment equipment or not

Russ

Ross R75 · 28th October 2018, 12:31

My take on this. It's not possible to buy a new 75 or ZT, therefore anybody buying one has no way of knowing if the alignment is in spec or not. Like others, I've had 4 wheel alignment carried out on a previous R75 that had no apparent issues. The rear was out of spec, meaning that the front could never have been properly adjusted on a 2 wheel alignment. The difference after having it done was unbelievable. It turned an OK handling car into a very sure footed one.

It makes absolutely no sense to have an alignment carried out on a system that assumes the rear wheels are in the correct factory alignment. They might be, but they might not be. If you use a two wheel alignment, you'll never know.

The simple and sensible way forward, is to use an alignment system that measures the alignment of all 4 wheels from a fixed reference point, like Hunter Hawkeye and others. If the rear alignment is good, you only pay for a front wheel adjustment. If the rear alignment is out of spec, you'll know about it and you can rectify it.

SD1too · 28th October 2018, 17:18

Quote:

Originally Posted by marinabrian

... I had the tracking set ... by an independent garage ... after collecting the car I drove home finding the steering wheel off centre and the car pulling somewhat to the right ... only one of the front wheels had been touched, and the rear ... tyres (brand new ..) were feathering after being driven fifteen miles.

"Pot calling the kettle black" springs to mind reading this.

Simon

hogweed · 28th October 2018, 17:46

Quote:

Originally Posted by clf

60mpg whilst accelerating up the M2 hill section is easily achievable (I remember the days having to stir from 3rd to 4th maybe 4 or 5 times driving up there in my R5.

Slow down approaching Sandyknowes and stop driving around at speed?

Well... that isn't necessary, because I go round the roundabout anticlockwise every other time, to equalise the wear. And I only moved back from the sleepy Cotswolds last year, so all my one-sided wear was accrued on country road with no roundabouts.

I do remember seeing 135 on the clock of a brand new 325i, back around 1980 or so, going DOWN past the Bellevue Bridge about 3 in the morning, with a very drunk police officer unconscious in the passenger seat, before almost tail-ending a car doing a normal sort of speed in front of me. I was only a little less drunk than the owner of the BM. In my defence, m’lud, I was young and foolish at the time, and haven’t had a drink for 11 years now

[QUOTE=clf;2681769]and fuel tank capacity. (approx 3/4 full if I recall)

not sure if this link will work, but for Roger, it gives a little extra confidence in their attention to detail.

https://www.facebook.com/ivankerrtyres/posts/1108562639319714[/QUOTE]

Yes it did thanks. Once I get some spare cash

Quote:

Originally Posted by BigRuss

On some it's a full tank depending on model year, or the appropriate weight added to the rear of the boot space or back seats to replicate any missing fuel in the tank

That's why it's essential to get the correct data for your year

Without doing that any adjustment is going to be incorrect, fancy alignment equipment or not

Russ

GAAAHHHH!!!!! Too much stress! Can’t cope! Errmmm… it was first registered December 2004 – does that help?

T-Cut · 28th October 2018, 18:00

Wheel tracking threads, especially long ones, always throw up some fascinating, sometimes wierd and wonderful stuff. And no less this one, so I'll add my take too.
Take Two
When I bought my Connoisseur, I soon became concerned about its tendency to drift left. I didn't think a big fancy machine like the 75 should do that, so it went back from whence it came to have the tracking checked. The MG Rover dealer did it twice in fact using their own gear (which failed to fix the effect) and using the 'latest' laser rig installed in a main MGR depot. That didn't fix it either. After testing the effect on different roads (accompanied by an MGR service tech, who couldn't really answer my questions) and doing a lot of reading, I concluded that no amount of wheel tracking would actually remove the syndrome. So, like many other 75 owners, I resigned myself to live with it.

I've no idea how MGR prepared the car for the laser gizmo.The tech guy didn't mention it, so whether they used a sack of sand or whatever I don't know. They didn't ask me to fill the tank beforehand, which would seem an obvious way of setting the datum. I guess they followed to RAVE manual, if that's where the datum is set - which raises an interesting point. In the thread I read:

On some it's a full tank depending on model year, or the appropriate weight added to the rear of the boot space or back seats to replicate any missing fuel in the tank. That's why it's essential to get the correct data for your year

Here's RAVE

Elsewhere, RAVE defines the Unladen Weight as the unoccupied car with a 90% full tank.

Shortly after my '4-wheel laser tracking' experience, I bought a Gunson TrakRite to see if I could do any better. Obviously a long shot, but for the cost of a tracking service, it's a neat way of testing for tyre scuff. Tyre scuff is the bottom line effect of tyre misalignment, but the Gunson gizmo doesn't get into the degrees and minutes gobbledegook but shows any scuffing as zero, good, bad or worse. Anyway, the Gunson said both rears had a small scuff, not much but that would slowly wear the edges. Obviously the toes were already in spec (MGR had said so - in duplicate), but I didn't want any scuff at all. So, a minor tweek of the trailing arm mountings brought the scuff pointer to zero. I checked the fronts and these were scuff-free, so a useful bonus. A drive straight after this tweek was surprising, it felt quite different, better. Basically, the Hunter had put my toes in spec but not on the sweet spot for my particular car. So a Brownie point to Gunson. Wonder what Mr Hunter would have said following the Gunson tweek? Interesting thought.

Which get's us into specifications. Over the years, I've noted for myself that tracking depots don't all use the same data. Quite where that leavesus is anybody's guess, but noting the following in this thread -

He was willing to change to the figures I got on this forum if the Hunter figures didn't work for me.

- only confirms my fears. I assume the 'forum figures' are the RAVE figures, but who know?

It's clear that some tracking parameters are interconnected, even though we can only adjust the front/rear toes. For example, the camber angle often changes after the front toe is changed. I've noticed it from the various printouts that members have posted. So it's fascinating to read here:

Cost for the alignment was £48 for 4-wheel alignment, but only charged £24 for the right (front side) as rear didn't need to be touched. But notice they changed slightly after front adjustment and a different reference input.

So another example of inter-dependency perhaps? But how can resetting a front toe alter a rear toe if using a different reference? What references are we talking about? Simplistically, I think we're seeing an example of operator and equipment variance - do the same test a dozen times and you'll get a dozen different anwers. It's normal and universal, even when working with stuff far more complex than a 4-wheel laser rig. So, my take on it all is to believe the degrees, but take the minutes with a grain or maybe a full pinch of salt.

TC

marinabrian · 28th October 2018, 19:06

Quote:

Originally Posted by SD1too

"Pot calling the kettle black" springs to mind reading this.

Simon

I don't quite understand this statement, have you forgotten to take your tablets again???

hogweed · 28th October 2018, 19:13

Quote:

Originally Posted by T-Cut

So, my take on it all is to believe the degrees, but take the minutes with a grain or maybe a full pinch of salt.

That’s it, I’m off – I’m going to jump.

Quote:

Originally Posted by marinabrian

I don't quite understand this statement, have you forgotten to take your tablets again???

I have some lovely tablets, if anybody wants some… white, yellow, AND blue. And green & white capsules. Best if all taken together, and always remember that doctors invariably understate the optimum dosage by around 80%

MSS · 28th October 2018, 19:44

Quote:

Originally Posted by hogweed

That’s it, I’m off – I’m going to jump.
................%

Don't despair. In Brian's terminology, it just means a roll of yellow string that doesn't stretch too much.

28th October 2018, 10:43	#51
BigRuss Premium Trader 75 CDT Tourer,2.5 Launch Saloon, Omipro MG/Rover (T4) Join Date: Jul 2007 Location: Liversedge, West Yorkshire Posts: 5,405 Thanks: 1,105 Thanked 1,340 Times in 661 Posts	On some it's a full tank depending on model year, or the appropriate weight added to the rear of the boot space or back seats to replicate any missing fuel in the tank That's why it's essential to get the correct data for your year Without doing that any adjustment is going to be incorrect, fancy alignment equipment or not Russ __________________ Replacement Key Service http://https://the75andztclub.co.uk/...d.php?t=244732 Full T4 Testbook diagnostics available. Diesel ECU repair and replacement. Options enabled or disabled as required. Diesel X-Power 135 and 160bhp, Rover 1.8T 150 to 160 MG 160 V6 to 177 upgrades available P.M. for details.

28th October 2018, 12:31	#52
Ross R75 Posted a thing or two Rover 75 Saloon Join Date: Apr 2007 Location: Edinburgh Posts: 1,535 Thanks: 137 Thanked 229 Times in 156 Posts	My take on this. It's not possible to buy a new 75 or ZT, therefore anybody buying one has no way of knowing if the alignment is in spec or not. Like others, I've had 4 wheel alignment carried out on a previous R75 that had no apparent issues. The rear was out of spec, meaning that the front could never have been properly adjusted on a 2 wheel alignment. The difference after having it done was unbelievable. It turned an OK handling car into a very sure footed one. It makes absolutely no sense to have an alignment carried out on a system that assumes the rear wheels are in the correct factory alignment. They might be, but they might not be. If you use a two wheel alignment, you'll never know. The simple and sensible way forward, is to use an alignment system that measures the alignment of all 4 wheels from a fixed reference point, like Hunter Hawkeye and others. If the rear alignment is good, you only pay for a front wheel adjustment. If the rear alignment is out of spec, you'll know about it and you can rectify it. __________________ Copperleaf R75 CDT 160

28th October 2018, 18:00	#55
T-Cut This is my second home Rover75 and Mreg Corsa. Join Date: Nov 2006 Location: Sumweer onat mote o'dust (Sagin) Posts: 21,753 Thanks: 341 Thanked 3,660 Times in 2,924 Posts	Wheel tracking threads, especially long ones, always throw up some fascinating, sometimes wierd and wonderful stuff. And no less this one, so I'll add my take too. Take Two When I bought my Connoisseur, I soon became concerned about its tendency to drift left. I didn't think a big fancy machine like the 75 should do that, so it went back from whence it came to have the tracking checked. The MG Rover dealer did it twice in fact using their own gear (which failed to fix the effect) and using the 'latest' laser rig installed in a main MGR depot. That didn't fix it either. After testing the effect on different roads (accompanied by an MGR service tech, who couldn't really answer my questions) and doing a lot of reading, I concluded that no amount of wheel tracking would actually remove the syndrome. So, like many other 75 owners, I resigned myself to live with it. I've no idea how MGR prepared the car for the laser gizmo.The tech guy didn't mention it, so whether they used a sack of sand or whatever I don't know. They didn't ask me to fill the tank beforehand, which would seem an obvious way of setting the datum. I guess they followed to RAVE manual, if that's where the datum is set - which raises an interesting point. In the thread I read: On some it's a full tank depending on model year, or the appropriate weight added to the rear of the boot space or back seats to replicate any missing fuel in the tank. That's why it's essential to get the correct data for your year Here's RAVE Elsewhere, RAVE defines the Unladen Weight as the unoccupied car with a 90% full tank. Shortly after my '4-wheel laser tracking' experience, I bought a Gunson TrakRite to see if I could do any better. Obviously a long shot, but for the cost of a tracking service, it's a neat way of testing for tyre scuff. Tyre scuff is the bottom line effect of tyre misalignment, but the Gunson gizmo doesn't get into the degrees and minutes gobbledegook but shows any scuffing as zero, good, bad or worse. Anyway, the Gunson said both rears had a small scuff, not much but that would slowly wear the edges. Obviously the toes were already in spec (MGR had said so - in duplicate), but I didn't want any scuff at all. So, a minor tweek of the trailing arm mountings brought the scuff pointer to zero. I checked the fronts and these were scuff-free, so a useful bonus. A drive straight after this tweek was surprising, it felt quite different, better. Basically, the Hunter had put my toes in spec but not on the sweet spot for my particular car. So a Brownie point to Gunson. Wonder what Mr Hunter would have said following the Gunson tweek? Interesting thought. Which get's us into specifications. Over the years, I've noted for myself that tracking depots don't all use the same data. Quite where that leavesus is anybody's guess, but noting the following in this thread - He was willing to change to the figures I got on this forum if the Hunter figures didn't work for me. - only confirms my fears. I assume the 'forum figures' are the RAVE figures, but who know? It's clear that some tracking parameters are interconnected, even though we can only adjust the front/rear toes. For example, the camber angle often changes after the front toe is changed. I've noticed it from the various printouts that members have posted. So it's fascinating to read here: Cost for the alignment was £48 for 4-wheel alignment, but only charged £24 for the right (front side) as rear didn't need to be touched. But notice they changed slightly after front adjustment and a different reference input. So another example of inter-dependency perhaps? But how can resetting a front toe alter a rear toe if using a different reference? What references are we talking about? Simplistically, I think we're seeing an example of operator and equipment variance - do the same test a dozen times and you'll get a dozen different anwers. It's normal and universal, even when working with stuff far more complex than a 4-wheel laser rig. So, my take on it all is to believe the degrees, but take the minutes with a grain or maybe a full pinch of salt. TC Last edited by T-Cut; 28th October 2018 at 18:02..