By: Joe Micciche - March '03
|Sagged stock suspension, blown shocks, 235 tires.|
The following article details removal of the stock coil springs and shocks on a 1996 Land Rover Discovery and the fitting of an Old Man Emu (OME) coil spring and shock suspension system. I chose an OME medium system, with 761 front springs, 764 rear springs, N45F front shocks, and N46 rear shocks. Other spring and shock installs should be similar, but you should verify before starting any work.
Don't let the simplicity of the suspension or the tool requirements lull you into unsafe work conditions! The Discovery is a very heavy SUV and extreme caution should be taken when working around it, particularly when working on the suspension. Land Rover recommends engaging the center differential lock (CDL), applying the parking brake, and chocking the wheel opposite the corner being lifted prior to jacking and removing a tire. In addition to these precautions, I have to add be sure to positively secure the lifted vehicle in at least two, or more, locations. I used two 3-ton jackstands, two jacks, and tires and wood blocks under the frame and axle to make sure the vehicle wouldn't fall.
|Tools required for the spring and shock swap|
|OME coil beside stock coil. Height difference doesn't equate to "massive" lift.|
|New OME rear N46 shock compared to stock shock.|
The tools required for this job are relatively basic, with no special tools required.
For the front end:
For the rear end:
For both ends, you will need a 27mm or 1 1/16" socket to remove the wheel lug nuts; PowerBlaster or other corrosion penetrant; access to a bottle jack; a floor jack with the capacity to lift the Discovery at least 20"; jack stands rated 2 tons or greater; a breaker or cheater bar for your sockets; anti-seize; and a torque wrench. With an adequate bottle jack, you don't need a coil spring compressor or pry bars to get the coils out. Soak all bolts with PowerBlaster a day prior to doing this work.
|Replacing the front springs and shocks|
The driver's front shock access is impeded by the air intake, and is the only corner with any obstruction. Open the hood and unclip the four retaining clips on the upper air filter housing. Follow the intake tube from the upper housing to the plenum, and loosen that band clamp. You can now pull the intake off and move it out of the way, with all electronics attached (do not stretch any wires).
You can now reach down and loosen the two inner shock tower retaining nuts with the 13mm socket. Space is at a premium, so you need to get creative with the ratchet extensions.
|The intake clearly obstructs access to the driver side shock tower.||Carefully move the intake out of the way.||The shock tower inner retaining rings are down there (view from over fender).||Retaining nuts can be accessed with the intake removed.|
Start at the driver's front by loosening the lug nuts and lifting the vehicle as high as possible with the floor jack placed on the outboard part of the axle. Place one jackstand just behind the radius arm mount on the frame, and another under the forward crossmember. Remove the tire, and lower the axle until the vehicle is resting on the jackstands. The swaybar will prevent overextension of the axle, saving your brake lines from potential damage. Slip the channel locks through the coil and grab the lower shock body (use an alternate tool that won't damage the shock body if you reuse this shock), then use the 19mm box wrench to remove the lower shock nut. Unfortunately, there is not room for a socket or any other device to help here.
Now reach in through the fenderwell and remove the two outer 13mm hex head shock tower retaining nuts. Maintain grip of the tower with your free hand so it doesn't bounce around near the intake and damage wires. Then simply lift the shock and tower up and out of the vehicle. Once out of the vehicle, remove the upper 19mm shock nut.
|The outer retaining nuts can be easily accessed with the wheel removed.||By unclipping the brake line retainer, you can force the axle down lower, simplifying coil removal.||View with the front shock and tower completely removed.||New front coil installed - note use of bottle jack to force axle down for easy removal/installation.|
Lower the axle as far as possible. Use a flat blade screwdriver to push the brake line plastic retainer out of its position - this will allow you to work the brake line so you can force the axle down farther. If the vehicle is lifted high enough, the axle will not come near the ground due to the swaybar. Place the bottle jack on the axle and use it to push the axle down far enough so you can reach in and pull the spring out.
|Genuine Land Rover Part Number 572087, shock tower securing ring.|
The shock tower retaining ring with the four captive bolts will fall away. If you snapped any of the bolts during removal, you can drill out the broken one and replace with a 5/16" fine thread carriage or flat-head bolt. The Genuine Land Rover part number for new retaining rings is 572087 and it uses 5/16" fine thread nuts and lock washers. Prior to spring installation, locate the retaining ring and start two bolts just to hold it in place. Install the new coil spring and ease up on the bottle jack to get light tension on the spring so the retaining ring is seated. Remove the two hand-tightened nuts.
Fit the lower bushings and washers to the upper shock mount and reinstall to the shock tower, then fit the upper bushing and washers and the new nylock nut. Make certain of washer orientation specified by the shock manufacturer. Position the shock into the coil and locate the tower onto the retaining ring bolts. Torque the four bolts to 10 ft lbs.
Fit the upper washers and bushings on the lower mount and guide the shock mount through the spring plate. Install the lower bushing, washers, and 19mm nylock and torque until the bushings begin to bulge.
Completely remove the bottle jack, secure the plastic brake line retainer, reinstall the tire, lower the vehicle, and torque the lug nuts to 96 ft. lbs. Refit the intake tube to the throttle body and the air cleaner housing, and this corner is complete. The passenger side front process is the same, but without any obstructions.
|Replacing the rear springs and shocks|
The rear coil springs are retained on the lower seat, and everything in the rear presents easy access. Again, start by lifting one corner and over-securing your vehicle for safety. It is imperative to lift the rear as high as possible by placing the jack under the locating arm mount - this will simplify coil removal.
Use a 19mm socket to remove the upper shock nut and work or pry the shock off the mount. Lower the axle as much as possible, if the vehicle is lifted enough the axle should not be near the ground (if it is, it needs to be lifted more). Remove the lower 19mm shock nut, and remove the shock. Be sure to get the underside bushing out of the cup.
|The rear coil seat has a retainer which must be removed.||Remove the shock before fully extending the rear axle.||Install the upper isolator to the new coil spring.|
Use a ratchet through the coil spring to get the 17mm socket on the retaining bolts. Hold the nut under the coil seat with a wrench and remove the bolts; then completely remove the retainer, including the two washers per bolt under the retainer.
Using the bottle jack again on the bumpstop plate on the axle, force the axle down until you can pull the spring out by hand. This should not come close to overextension of brake or breather lines. The lower seat will also fall away. Pry the isolator off the top of the old coil spring and fit to the new coil. Locate the spring plate to the bottom of the new spring and reinstall the spring, and ease up on the bottle jack until the spring just seats.
|The use of anti-seize on the upper shock mount will aid in future removal and help keep the poly bushing quiet.||Rear coil spring reinstalled. Again, note use of bottle jack to force axle down, which ensures spring is free of tension.|
Using the 17mm socket and box wrench, reinstall the lower retainer. Put the washers under the retaining strap, between it and the lower spring plate.
Fit the upper bushing and washer on the lower shock mount and guide the mount through the cup. Install the lower bushing into the cup under the axle, add the washer, and start the new 19mm nylock nut. Application of anti-seize to the upper mount will aid future removal and should also help keep bushing noise minimized. Fit upper shock eye to the mount, reinstall the washer and nut, and torque until the bushing starts to bulge.
|Post-lift, with 245/75R16 Goodyear MT/R's.|
Reinstall the tire, lower the truck, torque the lug nuts to 96 ft. lbs., and torque the lower shock mount. Repeat on the other side, and you are done!
Take a short drive to let things fully seat and check everything for tightness again, particularly the front shock tower retaining ring nuts.