Last update:

08/03/2005

  Front Suspension
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Replacing Front Shock Absorbers

Start by jacking up the vehicle and removing the wheels. You will be putting a lot of force into the suspension so make sure that it is very secure. My own standard is to have two separate methods of support, each of which will take the weight of the car if the other should fail. It is important that both wheels are off the ground or else the anti roll bar will be transferring compression force from the weighted spring into the strut that you are trying to remove. (A good example, incidentally, of how an anti roll bar does it's job when you go round the corner).
 
Mark the relative position of brake disk and hub and replace one wheel nut to stop the disk falling off.
In theory there should be the spring clip but these are often missing. Unbolt the caliper assembly (2 off 15-mm. bolt's) and hang it safely out of the way. Obviously you can't hang it on the suspension so I had prepared a Ty wrap loop and nipped it behind one of the Torx screws that hold the inner wheel arch. Make sure that the Torx screw isn't going to strip out of the plastic insert, you don't want the caliper falling on the floor. (I found several of my inserts were stripped and replaced them earlier in the year, they are quite cheap.) A second Ty wrap looped through the first and then through the caliper holds it nicely out of the way.  You will probably want to clean out the mud and Waxoyl the turret later on so remember to cover the caliper in newspaper before you do. Remove the disk.
 
In theory you need to remove the anti-lock brake sensor (shown with its bolt partly removed) from the spindle carrier but mine was so tight that I felt I would break it so I chose instead to unplug the sensor from the connector mounted on the wheel arch. Use a small screwdriver to "trip the catch". Tape up both ends to prevent muck getting in and unclip it from the brackets on the wheel arch and the strut. The downside of this method is that it leaves the wire somewhat vulnerable so keep it out of the way and protect it. The bracket on the strut can be removed at this stage. You will need to mount it on the new strut and there are two possible positions so note carefully where it goes.
 

Remove the two nuts from the link between the anti roll bar and the strut. The top nut is 15 mm. and the lower one 18 mm. As soon as they stop nipping, the ball joints will rotate. Fortunately Ford have thought of this and provided ways to stop them. Hidden in the end of the top stud there is a 5 mm Allen socket but you will need to clean the muck out to see it. The lower one has a fairly obvious 17 mm. flat so you'll need a suitably thin open-ended spanner. (The top one can actually be left until the strut is on the bench if access is difficult)

Remove the 3 off, 13-mm nuts and washers that hold the top of the strut and replace a couple of the nuts finger tight. Make sure that they are well on as the strut itself is very heavy, I could hardly lift it. Later on you will need an assistant to remove these nuts while you support the strut and remove it.
 
 


 

Next remove the nut from the track rod end. To remove the taper itself you'll need a suitable splitter. I have, in the past, managed without but it's just not worth the risk of damaging the gaiter. I bought the Sykes-Pickavant tool from Halfords for about £15, which seems to work well. To protect the gaiter after removal I cut out a piece of cardboard. At the same time I made a couple of "U" shaped cardboard masks to slip round the bottom joint and protect its gaiter. The bottom joint is not available separately from the wishbone (which costs about £75) so you don't want to damage it.
 
Remove the nut and bolt from the bottom joint. I found that the 18-mm. nut came off fairly easily but despite using a high-quality brand-new Torx bit I could not turn the bolt. Eventually, with about 150 pounds foot of torque, there was a crack as the spines sheared. Oh dear! More of this later.

Once the bolt is removed, the shaft of the ball joint is still a tight fit in the spindle carrier so I came up with a very useful trick. Place a washer and one of the old 13 mm nuts on top of the shaft and use the track rod end splitter to force it down. When the nut has disappeared inside, back it off, add another nut and repeat. This is much easier than trying brute force. Another tip is that the wishbone will definitely swing down far enough to clear. Originally, when I was struggling to get it out, I thought that this was the problem and tried jacking the strut back up but this is not to be recommended and is not necessary anyway.
 

With the assistance mentioned earlier the strut can now be removed and placed on the bench to separate it from the spindle carrier. Remove the 18 mm. pinch bolt and knock the casting off using a soft faced mallet and tapping each side alternately. If you open the gap gently with a cold chisel it will ease the job but be careful, cast-iron is brittle.


Now the bit I hate, compressing the spring. You cannot be too careful here, there is a huge force on the spring and you need to compress it further. Remember it normally supports over a quarter of a ton of car and perhaps twice that under load so there is an immense amount of energy stored here. The big danger (apart from a failure of the compressors) is that one of them will slip round the other side part way through the compression. It all happens very fast, there is a big bang and the spring ends up like a banana. All very frightening. Do not ever put your hands in between the coils or spring seats. I nearly lost my fingers.
 
I haven't a perfect solution. I bought a pair of new spring compressors and used them as well an older pair I already had but using four isn't ideal because one keeps coming loose as another takes the load. With hindsight, and I haven't actually tried this, perhaps three is the ideal number. Even with two it's important to keep them "in step" a little tightening of each at a time and don't be tempted to tighten one a lot or those narrowed coils become a ramp that the other compressor is all too keen to slip down.
 

Once the spring coils are safely restrained (check and double check, tapping gently) remove the nut from the top of the piston rod. You need to prevent the rod turning with a 7 mm Allen key so a ring spanner is called for, not a socket. This is an unusual size, 21-mm. I had to buy one specially.

It's now a simple matter to lift off the retainer, the top mounting, the thrust bearing, the upper spring seat, bump stop and gaiter. I found the last three stayed joined together, which is fine. Note how the spring fits into notches in both top and bottom seats. I marked all the bits with paint to enable correct reassembling.

All these (in reverse order) are placed on the new strut and the (new) lock nut retightened. You can now (equally carefully as this is where I got blasť and trapped my fingers) relax the compressors. Check everything seats correctly and start to breathe normally again.

Reassembling is pretty straightforward I replaced every nut and bolt with new ones, they are mostly locking nuts so shouldn't be reused and only cost about £4 a side for the lot. Strangely the spindle carrier pinch bolt's are supplied with the new struts but the lock nuts for the top of the piston rod are not and had to be ordered specially. I put plenty of grease round everything; in particular I packed the slots at the top and bottom of the spindle carrier where they clamp on to the strut and bottom joint shaft respectively. I think that these slots are the reason it gets so rusted up. Normally a bolt head is fairly well sealed, as is the thread, but these slots allow water into the middle section of the bolts. Unfortunately I'm not sure what to do regarding grease on those bolts which Ford supply preloaded with what I take to be thread locking compound?

Torque Settings (Nm)
 
Component Nm
Strut piston rod top lock nut 59
Spindle carrier to strut pinch bolt 85
Anti roll bar Link Assembly to Strut 48
Strut to wing turret (3off) 46
Lower arm (wishbone) to spindle carrier 80
Anti roll bar to Link Assembly 80
Track rod end retaining nut 28 (or 37 Needs investigation)
ABS sensor to spindle carrier 10
Brake caliper bracket to spindle carrier bolts
(
NOT caliper to bracket)
56
Road Wheel Nuts 85
   

 

Item/Code Description QTY  Unit Price My Notes
5030214 SHOCK ABSORBER 1 51.48  24 valve
5030217 SHOCK ABSORBER 1 51.48 24 valve
1138220 BOLT 2 0.49 Bottom joint pinch
6517149 NUT 4 0.36 Bottom joint pinch and Link bottom
1549071 NUT 6 0.29 Top mount
6194242 NUT-HEX . S/LOCK 4 0.49 Track rod and Link top
1668038  NUT-HEX 2 0.45 Strut piston rod top
6136989 BOLT-HEX . HEAD 2 0.95 Strut / carrier clamp
Last item was ordered but are no longer available as they are supplied with the strut.
Prices shown are each, excluding VAT and discount


Incidentals: -

The thrust bearing from the top of the strut seemed to be gritty so I stripped it down, cleaned it and re greased. The two plastic halves can be carefully prized apart leaving two (rather sharp edged) metal tracks, a plastic cage and 48 steel balls. These are loose so be careful that they don't go everywhere when you open it.)
 
And what about that seized bolt? I tried cleaning the rust off and drenching with Plus Gas. I tried belting the end with a big hammer but was frightened of damaging the lower joint, which I assume, is nylon inside. I didn't try heat because of the proximity of the rubber. I tried two lock nuts on the free end but they just spun back off. I tried force with a mole wrench, which of course destroyed the thread. I even considered removing the strut complete with the wishbone attached. (The bolt's that hold on the inner end of the wishbone seem quite accessible.) In the end I resorted to carefully drilling the bolt out from the head end. Start with a small drill and then increase in size. Don't make the steps in size too small of the drill will snatch. Use plenty of lubrication and take it very steady making sure you keep down the centre the bolt.  Eventually when most of the core had gone I sheared off the head and was able to knock out the remaining threaded bit. I did think at one stage that the bolt was threaded into the spindle carrier but it isn't, it's just a slide fit (at least when its new). The one on the other side of the car eventually knocked out after much twisting to free it up.
 
It took most of the day to do each side so was it all worth it? Yes, very much so, the car feels to respond much better to sudden maneuvers at speed (although obviously it's still a big car.) I've always been concerned about this aspect of my Scorpio, and changed the rear dampers earlier in the year, (which is just as well when we had a blow-out at high-speed on the French motorway.) Also there's now almost no overshoot at all on a bounce test.
 

 

 

 

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