Lower Control Arm replacement - Notes & what the manual misses out...

[haydent]

Symptoms (Im not 100% LCA are the problem, but it seems the first port of call), Car has 100k on it.

-Bumps/Dips cause car to veer or have reduced tracking.
-Soft breaking at high speed induces a wobble in the steering wheel if not resisted.

TDV8 Engine so specific LCA

Parts
LR029303
LR029305

I know non-genuine gets rubbished by some people, but its not always the case so I thought Id give these a try seems its a simple job I can do myself (if i have to do it again), and then I have a spare genuine set I can look at bush replacement with.

Ordered from bcionlineaustralia (https://www.ebay.com.au/usr/bcionlineaustralia) ebay $259 each including fast courier delivery, Box says "recovery" brand/logo on it, arms have part number label but no brand markings, so generic.


Pretty much just follow the workshop manual so far except one big hold up due to something they missed out.


Now im not sure if this is a TDV8 specific thing and they didnt tailor this procedure for their specific arms, but you cannot get the ball joint out of the knuckle with the half drive shaft in place !! maybe D3/D4 but not this variant.

Luckily not a big problem, just remove the axle nut (230 Nm when refitting), 32mm socket, and tap in wards, make sure though the LCA is already released from the chassis and knuckle supported by jack, so you can move the knuckle about, and pull it away from car a little then tap the shaft inwards, repeating in small amounts, as id be worried about hitting the half shaft if theres no where for it to go, so pull out a little, then tap back in, until the larger sprocket abs tooth wheel is out of the way enough that there is a bigger gap for the balljoint to move through.

- Nice video showing the axle retracted How to Replace the Front Lower Control Arms on a 2004-2013 Range Rover Sport - YouTube
(https://youtu.be/YcwlhE-spFs't=268)
- You need a 'bigger than normal' torque wrench, capable of 300 Nm but go for 350Nm

- The "washer" on the lca/chassis bolt head end is actually fixed and part of the bolt, so cant undo or torque from this end, the big washer on the nut end is fixed orientation to match the head end by 2 offset grooves along the bolt.

- When marking orientation you only need to do one end, but both wont hurt, but make sure you continue your mark out wide as when the big offset washer spins during removal it can rub off your mark.

- I used a jack to hold the lca up (if) when tapping to separate the ball joint as otherwise you wont even know it separated, as otherwise the knuckle wont fall away as already at lower extreme of hanging movement.

- You need a 24mm deep socket for the arm and shock bolt nuts due to length of bolt.

- Support hub at 462mm from axle center to guard lip before torque of to lca bolts (275Nm)

- I had to use a small bottle jack to 'gently' lift the catalytic converter up a little to get my torque wrench on the rear lca bolt's nut.

- I had to use a small bottle jack with 2 pieces of wood chocking it at the same angle as the shock, to push the shock back up so I could put the lower bolt (300Nm) on it and the the lca once all other torques done.

[haydent]

Update, it didnt help my problems, oh well, not a big loss as now just have a spare set of LCA. Going to look into brakes and wheel alignment and general research.

Here are some photos of things not mentioned in manual.

175624 175625175626 175627

[haydent]

getting front discs skimmed for $50 total fixed fixed the wobble !!

[Sascha]

Hi,

I'd be really keen to hear a bit more about this topic. I'm now on my third set of LCAs (ca. 160k km) since I bought the car and the wobbling is reappearing though the current LCAs have done only about 15k km yet. Leaving aside that it is concerning when this happens on the highway, it also is an expensive exercise when you need the workshop to do it.

Last fix include new LCA plus new brake discs and pads.

What is the expected lifetime> I drive 90%+ highway kilometres. Very little city driving. I saw 80k km+, sone stating close to 200k km.

Is there anything else that might contribute to the LCAs wearing out? I read in another post about sway bars?

Also, what products are favoured? The genuine parts or are the better quality aftermarket parts?

Appreciate any thoughts and advice on this topic.

Regards
Sascha

[haydent]

getting front discs skimmed for $50 total fixed fixed the wobble !!

this came back several times, and went away with skimming, so decided the pad must still not be retracting fully on one side, (which did appear to have noticeable more dust buildup on rim) , or there is something soft about discs (less likely)

so i put on new pads and discs, and second hand callipers, so far hasnt come back


Hi,

I'd be really keen to hear a bit more about this topic. I'm now on my third set of LCAs (ca. 160k km) since I bought the car and the wobbling is reappearing though the current LCAs have done only about 15k km yet. Leaving aside that it is concerning when this happens on the highway, it also is an expensive exercise when you need the workshop to do it.

Last fix include new LCA plus new brake discs and pads.

What is the expected lifetime> I drive 90%+ highway kilometres. Very little city driving. I saw 80k km+, sone stating close to 200k km.

Is there anything else that might contribute to the LCAs wearing out? I read in another post about sway bars?

Also, what products are favoured? The genuine parts or are the better quality aftermarket parts?

Appreciate any thoughts and advice on this topic.

Regards
Sascha

id be surprised that they would wear out that quick, even thinking maybe a miss diagnosis, what symptoms and how often would they occur ?

[Sascha]

this came back several times, and went away with skimming, so decided the pad must still not be retracting fully on one side, (which did appear to have noticeable more dust buildup on rim) , or there is something soft about discs (less likely)

so i put on new pads and discs, and second hand callipers, so far hasnt come back

I had that previously, new brakes/discs, machined them, still there. The mechanic explained that the wobbly control arms impact the brake discs and they need to be replaced together.

id be surprised that they would wear out that quick, even thinking maybe a miss diagnosis, what symptoms and how often would they occur ?

Yes, can't believe it myself. Symptom is steering wheel wobble when braking, most pronounced at speeds above 80km/h. Wheel balancing and alignment didn't fix it either, usually try that first.

[haydent]

that is not lca, ive been through all this replacing them too. its a warped disc from over heating, as mentioned earlier most likely the calliper is not retracting enough possibly from sticking guide pins or other calliper problems. there are service kits which i tried first but that didnt work, so i picked up some used front callipers.

you can get a disc skimmed for under $100 and it will go away proving the point.

another less likely culprit is that the disc material is too soft and not up to the heat generated via normal use, but this is just a theory and untested, as i didnt want to test brand new discs on my old calipers to find out so just swapped pads/callipers and discs

[BradC]

this came back several times, and went away with skimming, so decided the pad must still not be retracting fully on one side, (which did appear to have noticeable more dust buildup on rim) , or there is something soft about discs (less likely)

so i put on new pads and discs, and second hand callipers, so far hasnt come back

Different car, but my Volvo 740 was prone to a shudder under braking. A new set of front bushes ($50 and half an hour) fixed it for a while till they were shagged out again. It turned out to be a sticky caliper. A good dismantle, clean, new seals and it was good until I sold it. It did take me 2 years and 3 sets of bushes before I actually fixed it.

Uneven braking load on a front end can cause all sorts of issues that look like (or cause) something else. Now, If I'd had the forethought to go for a long drive and put the IR thermometer on each disc, I'd have picked it up earlier. The caliper at fault resulted in a noticeably warmer disc on that side. Not cooking enough to smell, but about 25% warmer.

[haydent]

ah yes i forgot that too, i do carry an ir thermo now in my car, as use it for checking the car and caravan brakes

[BradC]

ah yes i forgot that too, i do carry an ir thermo now in my car, as use it for checking the car and caravan brakes

I use my hand for the carvan brakes. If it smells like bacon I've got them adjusted too tight.

[Sascha]

Thank you Haydent and Brad, very much appreciated.

I suspect (and sincerely hope) you are right on the money with the caliper. Purely because machining discs, replacing pads alone never solved the problem. Like both of you I've tried this a few times.

What solved the problem was new LCAs and discs, but I suspect as part of the process the calipers get 'unstuck" (technical term...) for a certain period. I will try new calipers for the front including new disks. I hope I'll be able to report back with good news.

The car is just too good to give up on it :-)

Thank you again,

Regards
Sascha

[BradC]

What solved the problem was new LCAs and discs, but I suspect as part of the process the calipers get 'unstuck" (technical term...) for a certain period.

What I found was the vibration/shudder was caused by shagged bushes. The shagged bushes were caused by a sticky caliper. So the continuous excessive braking force on the bushes wore them much faster on that side.

[Sascha]

What I found was the vibration/shudder was caused by shagged bushes. The shagged bushes were caused by a sticky caliper. So the continuous excessive braking force on the bushes wore them much faster on that side.

That makes a lot of sense. And the worn bushes in turn also apparently, according to the independent LR mechanic, damage the discs through the shuddering.