I am having the lower control arms replaced on my 2006 LR3 SE that has 102K on it. I assume I will need an alignment.

What I don't understand is the "tight tolerance" mode that is needed to do a proper alignment. What I have been told is that the vehicle is put in this mode to limit the suspension travel so the alignment can be accurate.

Makes sense to me. Is the alignment always done in normal ride height? If the ride height changes, won't the alignment change too - not that I use off road at all, and only use access height for...well, access.

How is the vehicle put in this mode if the dealer is not doing the alignment? Is it absolutely necessary? Are there any options to the dealer process?

Thanks for your responses.

 

Below including the links should provide a bit of info re changing your lower A arms. I regard this as a good idea and presume you are doing it to get new ball joints etc - a good solution.

Yes, you have to do a four wheel alignment in tight tolerance mode. Take your 3 to a LR dealer or someone who has the computer equipment to put the 3 into tight tolerance mode, particularily if you have installed new tyres or do so once you have the new tyres installed.


Front control arm replacement forum links.

http://www.aulro.com/afvb/d3-d4-rrs/133172-suspension-front-control-arms.html


The 7 page good link with part numbers

http://www.aulro.com/afvb/d3-d4-rrs/101399-lower-ball-joint-issues.html


This is an early discussion on disco3.

http://www.disco3.co.uk/forum/topic23906.html


Link on LR repair forum with my part numbers etc.

http://www.lrrforums.com/showthread.php?19057-Replaced-Lower-A-Arms-rather-than-ball-joints.


Below is my experience re total replacement of the A arms. The cutting the bolts is because it is easier than trying to undo the rusted ones - well maybe they will un thread, but you want new un rusted bolts as they are cheap and everything else will be new. Basically for the cost of the A arms, you get the newer updated, (2008?), ball joint design, (greater articulation), plus new rubber bushings and less changeover labour.

A couple of years back, I had my Dealer replace both lower A Arms, (left LR028249, right LR028245), rather than just replacing the ball joints, (part number RBK500280). Also changed were some steering tie rods ends and both rear stabilizer bar rubber bushings, (part number LR015336, jpg below).

My 3 had 127,000 km, (79,000 miles), on it then, and this was the first time for ball joints, (city type pavement driving, no off road).

I wanted the apparently newer improved design of the ball joints, (part number RBK500280), so all new assemblies seemed the best route to achieve that goal. I therefore also got new lower control arm bushings as well.

In terms of labour, well flat rate does not help much, but if you were to do the job yourself, buying the new assemblies is I think the route to go.

Instead of much banging and pounding and then cutting each of the three bolts off that hold the assembly on so you can press out the ball joint, you instead just plan on cutting the three bolts and install all new A Arm assemblies. In my case, the dealer only had to cut one bolt on each side, the other two unthreaded, and the job was done. Also you will have purchased all the needed parts instead of running around getting more bolts etc and the job is relatively straight forward.

Yes, you will need a 4 wheel alignment, and you will have to get someone to do that for you but the using all new parts, the front end replacement is relatively doable.

There is also the view that a lower arm is only good for one replacement ball joint as there is some thought the hole can get distorted from repeated replacement. I am hoping to get closer to 200,000 km, (125,000 miles), out of these new ones - we will see.

After a few days of driving around, I was happy to say that my 3 is now quieter inside, (less suspension banging and road noise from pavement joints coming into the cabin), so at least that part of the plan has succeeded.

New bolts, nuts, and washers, (2 of each per side), to hold the A arms back on should also be purchased. Even if one does not have to cut the bolts and they appear reusable, nice new smooth clean ones are preferable to mate up with the new rubber bushings, (no internal tearing). RDI000034, bolts; RYF000203, washers; FX116056, Nut -Flanged, are the part numbers.

You will require a total of 4 of each for the two arms, and that assumes the bolts that ties each shock assembly to each arm are still OK, which they probably are.

 

I also had an alignment done after replacement lower control arms. As my LR was long out of warranty, the independent shop that did it farmed the alignment out but they used their auto logic tool to enable the tight tolerance mode before dispatching it to the tire shop.

If they're a good alignment shop they may already know what needs to be done - no harm in asking them if they know or have experience of LR vehicles. They may already carry the tooling to do this. There's no "user" controls I know of to achieve this, has to be done with the right diagnostic tools either at the dealer or you buy yourself (IID, Nanocom, Faultmate etc).

I was told the alignment is less accurate if not tight tolerance, but no idea how bad that is.

 

Fortunately there are lots of RR Sports around now so getting a wheel alignment on a 3 so not so much of a near impossibility any more.

At least independent alignment shops know what you are talking about now when you request tight tolerance mode even if they cannot do it - and yes, it matters.

Also make certain the steering wheel is straight ahead as the steering wheel angle sensor will pick it up if not and throw a suspension light as the yaw sensor says the 3 is going straight down the road and the steering wheel sensor says the 3 is turning, and well, the baby cries.

 

Tight tolerance mode is really not needed, and in my opinion will actually do more harm then good when doing an alignment on these.

It changes the sensor offset tolerances to +/- 5mm, instead of 10. In theory this is great, a better alignment, however in practice there are two major downfalls.

First off, as soon as the vehicle is released from this mode, it goes back to the 10mm tolerance, so the tighter tolerance when setting it doesn't mean too much, as that is not how you will actually be driving the vehicle.

Secondly, and far more important, is that when making the adjustments, there is a chance for the vehicle to level itself(changing any geometry settings already made, which in turn changes everything still needed to be made) more easily.

The two big things that need to be addressed when having an alignment preformed on these are that the vehicle is raised, and then lowered to normal height, while in motion, directly before pulling onto the alignment lift, this will get the heights as close to normal as they will be while you are driving, and secondly, again, more importantly, that a machine capable of rolling compensation is used. Older machines used jacking compensation, which will dramatically change the height of the vehicle, and if not allowed to properly level itself out after compensating, the settings can be made incorrectly.

A jacking comp. machine can properly do one, but it takes some getting used to on the part of the alignment tech, so your standard tire shop that doesn't do these everyday may not get it right.

 

I agree with Roverguy7. We didn't get tight tolerance mode for almost a year and even then we understood how to do it correctly. The reason the indys put it into tight tolerance is because they don't understand how the system works. Plus its easiest and better for the vehicle to leave it in park idling so the system compensates after it gets jacked up and moved back and forth. Finally settling in to the optimal height that the vehicle sits at while driving. That way the alignment comes out true to form. I have seen more issues with tight tolerance then not using it. Plus when you install new arms you are supposed to drive it ten miles or let it sit overnite for twelve hours or more. Check the bulletins it states drive ten miles to allow them to settle. Otherwise they chew the tires off.

 

Rovin - so what you're saying is I can take it to a "standard" alignment shop and they don't need to put it in tight tolerance mode. They should let it idle in park and have it set at the ride height that I use most of the time. I should not attempt to have it aligned until I have driven it at least 10 miles or let it sit overnight.

Is that an accurate summary? What about Roverguy7's requirement that a rolling compensation rack is used? Is this a common type of alignment rack?

 

Resurrecting as I'd like to know the answers to these questions as well....

 

Hey guys, I changed my lower control arms awhile back on my own and did the alignment on my own as well. I used a laser machine and all to do the alignment and all i did was raise the 3, then lower, then normal height. Drove it onto the alignment machine and did it. It runs straighter then an arrow. Yes I did all four wheels too. I wouldn't worry too much about the this.