Replacing front suspension bushes.

[djm16]

I have already posted questions about the bushes, whether to use urethane or not. Here is my answer, and how to do it.

It is possible to replace all the bushes without removing the front wheel hub from the stub axle or detaching the ball joints.

First, the following are urethane bushes from Whiteline, sourced through my local suspension workshop Wilkinsons. I am told that Whiteline also own Nolothane, and that the magenta / black coloured bushes are "better" than the red Nolothane. They certainly feel more malleable to me than the red Nolothane I have used elsewhere.

Radius rod front end: W52400 (warning, these are pricey!).
Radius rod rear end: sorry, I did not get a part number for these, but they were a standard Range Rover part.

*Upper arm: W71600
[edit 07/23: I have just tried the KCA399 set and this will not work] *Lower arm: KCA399 if you want to use offset bushes to reduce the positive camber or W53404 which is straight.

*in the end I did not use these, but bought a set of bushes from Scotts Old Rubber. He does not do the radius rod bushes in urethane, hence the ordering them from Whiteline.

The first step is to remove the shock absorber and the two triangular plates that secure the lower end of the shock absorber to the lower arm. (Those shocks are Konis. Unfortunately I do not remember what part number, but Koni Australia were very helpful in finding something that is usually fitted to a Falcon or similar, but would have the correct rebound, lenght and throw).

[djm16]

The next step is to remove the brake caliper, feed it through the gap where the shock absorber was, and hang it up out of the way so that the brake line is not under tension. The two caliper bolts have a lock plate behind them. If you are going to reuse it, then it will need annealing by heating to a red glow and allowing to cool slowly, without permitting any infinitives to split. I know, bad practice, but part from the UK are taking over a month.

[djm16]

The next thing to come off is the track rod. This make room to get at the radius rod, and allows the lower arm to drop a lot further. I took the track rod off completely after I got tired of it swinging back down and into the way. I have a black eye where it swung down with be underneath.

[djm16]

I did try dropping the lower ball joint just for the hell of it, and to see if it was still free after being on the car for several years since I last did this job. I wedged up the upper arm with a block of wood, and allowed the wheel hub to dangle. I don't know what the "usual" method of getting the ball joint loose it, but slackening off the two retaining nuts, and then a hearty blow or two on the lower arm with a lump hammer did not do it, so I gave up at that point, and then just dropped all the tension off the torsion bar.

[djm16]

The most difficult part of the disassembly is getting the nut off the rear end of the radius rod. It is bad enough removing the split pin, but he nut will only clear the chassis when the radius rod is at a certain angle, which means jacking up the lower arm with a trolley jack and block of wood under the ball joint. So nuts off both ends of the radius rod.

[djm16]

With the reduced tension on the torsion bar, and the lower arm supported (raised a little) by a trolley jack, we can now remove both upper arms safely, and then hang them up. At this point the lower arm can be dropped way below the usual limit of travel so that there is close to zero tension on the torsion bar, and the lower arm can be disassembled safely.

[djm16]

Now we get a good look at the lower arm bush. It is not the greatest design, as the bush has no shoulders to take the pressur of braking, causing the lower arm to drift backwards, destroy the projecting bit of rubber bush and start fouling the three bolt heads holding the lower arm bush pin to the lower arm. Of course, engine oil and steering box fluid dipping on to it do not help either.

Before you can drift the lower arm off the pin, you have to remove the three bolts (2 long, 1 short) holding the Lower Arm Mounting Pin Housing to the chassis. The the set of the torsion bar was preventing the housing from clearing the steering arm, hence the wedge of wood between torsion bar and chassis.

[djm16]

With the Lower Arm Mounting Pin Housing out of the way you can see and get to the three bolts holding the pin to the lower arm. I suppose strictly speaking, it is not actually "necessary" to remove the pin, but it does make it easier to clean up the corrosion on the pin and also check the positioning of the torsion bar in the lower arm.





We are looking at the driver's side suspension here. In this case the torsion bar comes to a few millimetre short of the backside of the pin. The passenger side was different. I have already posted about the difficulties I had with it. The lower arm was fouling the pin mount bolts quite badly as the torsion bar was too long. There was no way it was all going back together again gracefully with new bushes that had shoulders on them. So with the passenger side, I removed the torsion bar a cut 7mm off the end of the bar with a cutting disc on and angle grinder. That is tough metal. I didn't time it, but it felt like 20 mins.

[djm16]

The lower arm bush is relatively easy to press out of the Lower Arm Mounting Pin Housing, a vise and some large sockets are all that is needed.

As I had bought the new bushes from Scotts Old Rubber, they came with new crush tubes, so it wasn't actually necessary to strip and reuse the crush tube for the lower arm bush. However I did need to rescue the crush tube from the radius arm front bush. This bush was quite awkward to remove. I could have lifting the whole assembly (wheel bub, ball joints and lower arm) onto the bench and done it there. Instead I left the lower arm supported by the torsion bar and use a G clamp to push out the bush.

The rubber bushes had become bonded to their crush tubes. By making a single cut to the bush, peeling away as much as possible, shaving back the rest with a box knife, I eventually got back to some metal. Then a couple of grades of sand paper to complete the clean up.

[djm16]

That is the disassembly complete. Time to play with the dog, and then start by pressing new bushes into place. The lower arm bushes are two piece. The upper arm bushes are single castings, with lips or shoulders on them that makes it quite tricky to press them into the upper arms. One went in first time, the other ricocheted around the shed a dozen times before submitting. The instructions probably say somewhere not to grease the outer surface of the bushes, as only the inner surface is meant to rotate on the crush tube, but honestly it is very difficult to get them sited without a trace of grease.

Reassembly is just the reverse of the disassembly, finishing with winding the tension in the torsion bar back up. It is a good idea to tighten the castellated nuts pretty firmly against the crush tubes, as the crush tube is not meant to rotate on its pin, and if it does, it will cause wear.

As all the pins were partly corroded, after cleaning them up, I applied a coating of rust preventer (Waxoyl for UK types) before remounting.

Remembered to add split pins, and then re-adjust the toe-in on the steering link rod.

[Ken Nelson]

Wow djm16, that is an impressive writeup and set of pictures. You should send that to the editor of Take Five for him to print. Having just done this job including regreasing my ball joints I know how labor intensive this all is. In the future replacing bushings only would be much easier if the hub and ball joints didn't need to be removed and taken apart. The radius rod bushings are especially difficult to replace and I wish I had known about the Whiteside urethane bushings to use instead of the rubber ones. I must say that I hope never to have to do the job on my car again (fingers crossed!) Thanks for the excellent writeup.

[djm16]

Thanks Ken. The Offside took the best part of a week (partly because of the oversized torsion bar) and because I was feeling my way around the technique. The drivers side took little more than a day to strip and re-assemble. The radius rod bushes were a major reason to be doing the job in the first place, and like you I never want to do it again so was determined to use urethane all round.

[MK IA Norway Viking]

Good evening - what an amazing job done ! And thanks for sharing, very very useful for guys like me who also do the mechanics myself in my shed. No electricity there so I work with battery lamps. I presume they will go through many charging cycles before I could complete this job ...

My car is an MK IA and, fortunately, the bushes are OK. Just replaced the shocks yesterday (front and rear) which was quite easy, actually. As always, the first shock to replace ate 80% of the total time ...

How often do you lubricate the balls on the front suspension and is there a particular trick to it ? Which grease would you recommend ? How to check if the balls are bad or not ? Difficult to replace the rubber "bellows" (on of mine is ruptured) ?

Kindest regards,
Christopher
Oslo
Norway

[Ken Nelson]

There's a lot written up on the forum about ball joints and how to remove and take them apart to regrease them. Use the search feature to find them. The ball joint are exceedingly robust and mine had obviously gone years without servicing and were all in generally good shape. The rubber boots protecting them perish fairly quickly though and you should use either urethane or silicone boots for replacements. But the torsion bars must be released fully to work on them (can be dangerous) and the front spindle and hub need disassembly to replace them. It's a rather involved job. Again, look up "P5B/P5 MK3 Lower Ball Joint Assembly" (https://roverp5.proboards.com/post/95552/thread) although I believe the MK1 Rover has an older style ball joint that uses different lubrication perhaps.

[MK IA Norway Viking]

Hello Ken,
Thank you, I shall check this when I get 'round to servicing the balls. Meanwhile wishing you a fine day.

Best regards
Christopher

[Phil Nottingham]

I fully endorse Ken's comments! Read up and be careful - mistakes could be fatal