The Mitsubishi Pajero Owners Club®

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Changing your rear coil springs is actually an easy job which most DIY mechanics can do at home and many people are actually put off by thinking it is difficult when in reality it is simple; many modern coil springs crack and this is the usual cause for replacement and this is for original factory fitment springs. This does NOT cover uprated springs or lift springs which raise the vehicle, but the process is similar. Much of these procedures also apply to the MK III models.

Tools you will need:

Good quality heavy duty coil spring compressors. (cheap online items don’t cut it as they are not strong enough)

19mm socket and ratchet, power bar to fit the socket and possibly an extension pipe for leverage.
19mm ring spanner.
17mm ring spanner.
Short extension 2” long is preferred but not essential.

Chain wrench, Stilsons, or similar to hold the shock absorber and stop it turning.

Small 2 tonne hydraulic jack, the shortest you can find.

Mole grips or small heavy duty G cramp or similar.

Large trolley jack.
Various wooden blocks, I have chock blocks which are 4” square and 24” long.

Thread lock, I use Loctite 242e but any can be used.
Copper grease or similar

Park the vehicle on flat solid ground and chock the front wheels.

Raise the rear of your vehicle with your trolley jack under one of the suspension arms jacking points until you can jack no higher and put chock blocks under your wheels to raise your car and drop your wheels onto the blocks so it is raised off the ground and weight is still on your wheels.

Crack all your wheel nuts with your breaker bar and 21mm socket, alternatively use the vehicle wheel brace and unlocking tool if you have locking wheel nuts, do NOT remove the wheel nuts yet.

Raise your vehicle again using the trolley jack under the lower suspension arm and you can put some packing timber under the opposite suspension arm and use your small hydraulic jack if needed to assist in raising your vehicle.

Get plenty of your chock blocks and put them under the rear of your vehicle and note the inverted U shaped mounting channel which the lower suspension arms mount onto; build your wooden pack under this going North/South with your first layer, East/West with your next layer and ensure they are fully spaced to give the widest footprint possible. As you near this U channel ensure you are NOT binding or under your lower suspension arms and put thin pieces of wooden boards under if needed.
Lower your jacks slowly and evenly until your vehicle weight is fully on your timber pack and is solid; once you are satisfied it is safe fully lower your trolley/hydraulic jacks and remove them from under your vehicle and undo and remove your wheels, you will be glad you cracked your wheel nuts now.

Begin working on the nearside of your vehicle (RHD models) as it has the exhaust this side and it is the most difficult to do; follow your lower suspension arm to the outside of the vehicle and at the outer end you will see two nuts and bolts, the inner one goes through the bottom of the shock absorber and the outboard one goes through the hub carrier.

Clean both the nut and bolt if necessary and I use a rotary wire brush on an angle grinder and put your 19mm spanner on the bolt head (front of the arm) and 19mm socket on the nut (rear of the arm) and fit your power bar to the socket and just crack the nut and bolt until they are loose.
Repeat this with the outer nut and bolt which goes through the hub carrier; do NOT fully remove the nuts and bolts yet. On some models you may need an extension pipe adding to your power bar and if you do I suggest you get replacement nuts and bolts, Milners do them.

Put your trolley jack under the lower suspension arm and lift until it just begins to lift off your timber pack and you have compressed your spring as much as you can the easy way; fit your coil spring compressors to the coil spring and tighten up just enough to hold your coil spring in the compressed position. Be aware of the exhaust and the shock absorber as they can become bound up by your spring compressors.
Lower your trolley jack and your coil spring compressors should hold your coil spring in the compressed position and check; lift your trolley jack again so the lower suspension arm is lifted by 3-6mm as the shock absorber is now holding it and you release this tension. Fully undo the shock absorber bolt and remove it followed by the hub carrier bolt and note that both nuts and bolts are the same size but the hub carrier bolt is longer so do not get them mixed up during reassembly.

You can prise your shock absorber up and release it from the lower suspension arm but the hub carrier usually needs a pry bar, screwdriver, or brute strength to release if from the bottom arm and once removed the bottom arm will pivot on the inner suspension bush. This inner suspension bolt and bush is never removed as they are offset bolts which set the rear camber and rotating the bolt will throw the rear camber out and wear your rear tyres excessively and affect the vehicle handling adversely.  
With both your shock absorber and hub carrier free you can push the bottom arm down and free but the nearside often binds and doesn’t go down easily and you now need a bar to prise it down far enough to release the spring, note that the top arm and hub carrier should NOT be forced down.

If you force the top arm and hub carrier down it can exceed the designed angles of the drive shaft joints and permanently damage them both so avoid prising down the top arm and exceeding the designed drive shaft joint angles.

Once you lower the bottom arm sufficiently the coil spring will often fall out on its own and note you have top and bottom rubbers for the spring to seat on and these can also fall out so note them and any coil spring coverings such as plastic sleeving as this is an anti friction sliding item. If you need more room you can undo the shock absorber top nut using the 17mm spanner and you will find that as you release the nut it suddenly becomes tighter so never try to fully remove it as just releasing it will allow you to move the shock absorber to one side sufficiently far to give more room.

With your coil spring removed it is time to prepare for its replacement and this begins with your rubber insulators so remove the bottom one and clean up any rust and potentially repaint the bottom arm if necessary and note the spring carrier and rubber have stepped stops so align them.

This next step is purely optional and maybe ignored, but if you are an engineer or a perfectionist you may well do it. Over time rubber and predominantly rubber components deteriorate and this is due to their natural oils drying out which allows them to fail and while you can get replacements they are often expensive and not readily available but you can get various spray rubber treatments. These revive rubber components by having a synthetic from of their natural oils in a synthetic carrier and you spray the components and it absorbs these oils back into them; some go even further and I use one which also has a PTFE additive which is attracted to metals and this lubricates them and prevents them corroding.
You spray these components in their decompressed state so remove the bottom rubbers and hang them up. Spray the top rubbers in position as they may be difficult to remove, become damaged when removed, or be too difficult for some people to remove; spray the hung bottom rubbers as many need leaving from 3-20 minutes to allow their oils to be absorbed and then refit.

Put your spring compressor on your new spring and compress it slowly and evenly until it is compressed by 50mm or there abouts and do this slowly and evenly as they have tremendous tension and can often bend the threaded portions of the best spring compressors.
Refit the new spring and rotate it until it is up to the stops and in the correct position, check the new spring is the right way round and not upside down as many are actually different top and bottom and when you remove your old spring this is best checked for position.

Put your trolley jack under the lower suspension arm and jack it slowly until the hub carrier is just above its mounting position as it will often need jiggling to get it to correctly align with the bush and pump your jack a little more to see if it engages in the slot, if it lifts the upper arm you need to stop this. On top of the upper arm at the outer end is a semi circular section and above it is the chassis bump stop plate and you can put the bottom of your jack inside this semi circular section with the top of your jack under the bump stop plate and you will need either Mole grips or a G cramp attaching to this plate to stop the top of the jack sliding off. Remember the hub carrier will turn as well as go up and down on the upper suspension joint and it is crucial to get this aligned until the bolt can pass through easily and once this is achieved you remove the bolt.
Coat ONLY the shank of the bolt and NOT the threads and insert the bolt; fit the nut and tighten up and just nip it, do not fully tighten it yet and repeat this with the shock absorber bottom bolt so they are both installed nut not tightened and you tighten the shock absorber top nut.
Remove both the shock absorber and the hub carrier bolts nuts and put threadlock onto the threads and refit the nuts and correctly tighten

You can now remove the spring compressors and the spring will remain in position and the shock absorber will stop it dropping too low and this side is now done.

Repeat this on the offside and in most cases this side is easier and you have replaced your rear coil springs.

Many people simply want to change their shock absorbers and these are fairly easy and they need changing either before or after changing the coil springs as they rely upon the shock absorber to limit the amount of suspension travel it has, and to prevent the suspension from dropping too far and damaging the drive shafts and their universal joints.

I would suggest buying a shock absorber kit rather than a single shock absorber as a kit contains new rubbers, bolts and nuts so everything to do the job and with new fittings, Mitsubishi Shoguns/Pajero’s from 2000onwards only used gas filled shock absorbers and I would recommend replacing them with gas filled shock absorbers. These are large and heavy vehicles and their shock absorbers have to work hard and gas filled shock absorbers work to transfer the heat from the oil to keep them cooler and this gas cushion stops the oil from frothing and as they constantly work, even on the smoothest roads and this means they constantly generate heat.
Heat is conducted away through airflow and as the gas conducts the heat from the oil to the steel body the passing air removes the conducted heat from the steel body which is fine at normal road speeds but put a heavy towed load on the back or go off road and this all changes as you haven’t got fast flowing air to remove this additional heat.
This constant excess heating and cooling does them no good and the oil soon deteriorates due to them working at the top of their working heat range or even regularly overheating and shock absorber oil is like most other oil in that overheating rapidly accelerates its wear. Try getting frothing or poor oil when off roading and it’s like having suspension made of jelly and blancmange and your vehicle becomes inherently unstable and your stopping distances increase massively.  

If you are doing, or have changed your coil springs then changing your shock absorbers at the same time makes sense as you have new rear suspension and you have most of the tools out that you need and we begin with the layout of the shock absorber which is that the body of the shock absorber is at the bottom and the piston rod goes through the shroud to the top. This shroud is a larger diameter than the piston body and slides down over it to give the piston rod some protection from the elements so now we know the shock absorber body bolts to the lower suspension arm while the piston rod bolts to the upper mounting point and this is critical information.
Most shock absorbers piston rods go up and down but also rotate and this is a problem when removing them as often the tight top nut makes the piston rod rotate and to get the nut off this needs to be prevented from rotating.

If our old shock absorbers are scrap we can cut them but we don’t want to be cutting into the body as the gas and oil can spray all over you and this is to be avoided; this means we must cut the shroud so we can access the piston rod to either hold it to prevent it from spinning while we undo the nut; or we can cut it safely rather than cutting the body. I prefer to cut the upper shroud first and access the piston rod and this can often be clamped with Mole grips and if they are in good condition they will prevent the piston rod from spinning while you undo the top nut.  
Allow the suspension to fall to its lowest level and the shock absorber is fully extended and holding the suspension, place a jack underneath the lower suspension arm and jack until it just begins to lift the suspension and your jack has the weight and your wooden pack is still under the real suspension arm carriers. Cut your shroud with a hacksaw, tin snips if it is thin or a chain type tube cutter and this only needs to be large enough to access the piston rod with your Mole grips. Grab your piston rod and undo the top nut and hopefully it should come loose and come off; if not you need more holding power on your piston rod and I find quality Stilsons work.

Prepare your new shock absorber by checking it has its bottom bush fitted in the eye, most replacements come with them fitted but some don’t and they need fitting; start on the top and fit the bottom metal plate and then the bottom rubber. Charge your new shock absorbers by putting it in the upright position and pushing down on it and it will return to the upright position so do this a few times and then put the shock absorber into position in its top mount and fit the top rubber and the top metal plate and apply copper grease to the threads and fit the nut loosely. Go to the bottom and line the hole up and put the bottom eye bolt in after greasing the shank with copper grease, put threadlock on the threads, fit the nut and fully tighten and go back to the top and fully tighten the nut and release and remove the jack, refit your wheel and repeat on the other side.

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