Suspension Installation Instructions

Last updated: May 2, 1998

INTRODUCTION

Installed Rear Shock

I installed all of the components at once - shocks, springs, anti-sway bars, and anti-sway bar braces. To install just one of these, check inside of the directions below. It was easier to just do the whole thing at once, as the springs/shocks required the anti-sway bars to be removed most of the way. The bars could be done separately without having to do anything with the springs. To just do the shocks OR springs, you will have to take the other off as well. So you might as well replace both at the same time.

This is actually a pretty simple procedure. Do not let all the detail in this procedure throw you off. I did it with just the diagrams in the shop manual to go on, plus one diagram that Tri-Point sent me with the Penskes. I added a lot of detail here in my procedure, as there are some steps that are much easier to do one way than another. I found out the hard way. If you do these in order, it should go a lot easier. And it was pretty easy even doing it the hard way.

I installed the rear components first, as it seemed a little more straight forward (less parts). After doing the whole thing, I don't think it makes any difference which you do first.

Portions of this are specific to the Penske shocks, so determine what applies to your installation if you are not installing these. I tried to mark these steps and tools with an asterisk (*).

PARTS



ADDITIONAL PARTS



TOOLS



INSTALLATION

REAR SUSPENSION - DISASSEMBLY

    Rear Swaybar Comparison

  1. Jack up the rear of the car and set it on jackstands.

  2. Remove the wheels.

  3. Remove the rear strut tower brace. The three bolts that attach are fastened to the studs on the top of the shock assembly and hold that unit in place.

  4. Unbolt the anti-sway bar end link from the bar itself before attempting to remove the bolt at the bottom of the shock. This will make it easier to get the bolt out of the bushing. (If you are going to replace the anti-sway bar, you might as well remove these at this point anyway.) Remove the bolt at the bottom of the shock.

    Spring Compressor

  5. If you are replacing the anti-sway bar, finish removing it at this point. There will be two bolts at each side that attach the mounting brackets to the frame of the car.

    For more detailed information on removing and installing the anti-sway bar mounts, see the page on the Widefoot mounts.

  6. With the strut tower brace removed at the top, and the anti-sway bar end link bolt removed at the bottom, the shock is not free, and can be removed from the car. Pry down on the upper control arm, and the shock will pull free.

  7. Once you have the springs/shocks out, use the spring compressor to disassemble them. (Shown to right.) The stock top rubber mount and rubber washers will be re-used.

    Rear Shock Comparison



REAR SUSPENSION - ASSEMBLY

    Rubber Mount

  1. * Remove the stock top rubber mount. This is the big rubber donut with the accordian-like sleeve on it.

    The directions I got from Tri-point said to trim it, but I found that it serves no useful function, and it squeaked against the new spring perch. I confirmed this with Tri-Point, and they said it should just be removed. Just in case, here is what I had written on trimming it:

    Cut off the accordian-like boot at the base of the metal plate inside the bottom of the mount. The top locator of the Penskes will sit inside the lip of the metal plate. Use it to determine how much of the boot will need to be trimmed. Trim just enough so that the locator will sit flat inside the metal plate.

    The stock mount is shown in the photo to the below and to the right. It is the one on the left of the photo. The trimmed mount is in the same photo, on the right. The locator is shown there also, at the top on the right.

  2. * Drill out the two stock rubber washers (shown to the right) on each shock with a 1/2" drill bit. These have extremely hard metal inside, so use a cobalt bit or other bit designed for this. (I ended up going through three cobalt bits for the fronts and the rears.) A drill press helps a lot but is not absolutely necessary for this operation. Clean up the holes with the Dremel tool w/ sanding attachment or a rat tail file.

    NOTE: Be very careful in drilling these; mine rattle on the shock rod since my holes ended up being a little bigger due to the drill rattling in the hole since the material was so hard. I get sort of a jingling rattle from the back of the car and I pretty sure this is what it is. You may want to consider having a machine shop drill these it is such a pain in the butt.

    Rubber Washers

  3. Assemble the new shocks/springs, using the stock mount (with rubber donut removed) and lower rubber washer. Tighten the 1/2" nut at the top of the shock down to the torque listed in the shop manual. (WARNING: this is NOT the small nut that is part of the top of the shock - that is the compression adjustment. The compression adjustment nut has small holes in it.)

  4. * Use the bump stop that came with the Penskes, not the stock one. This is the large white rubber/silicone piece on the shock rod (inside the spring).

  5. If you are replacing the anti-sway bars, assemble the new bar. Grease the urethane bushings with lithium grease. (I used Valvoline Synthetic.) Just grease the inside of the bushing, no need to do the outside where the bracket will sit. Urethane bushings will squeak really badly if you do not grease them. Install the urethane bushings on the bar and put the stock mounting brackets on the new urethane bushings. Install the locator clamps (but do not tighten yet). Put the new bar on the car, but do not bolt it into place yet.

  6. Optional step - add a grease fitting to the rear urethane anti-sway bar bushings. Drill a 1/4" hole in the metal bracket, through the bottom (this is the round side of the bushing, and it will point down when it is installed on the car. This will be the highest point of the bushing that points up if you lay it flat on the ground.)

    Insert the bushing in the bracket, and drill a 1/4" hole through the one you just drilled in the bracket, entirely through the bushing.

    Note: I used 1/4" standard grease fittings; you may get a different size. Drill the appropriate hole.

    Installed Shock

  7. Install the shock/spring by locating the three studs on the top mount in the holes in the body.

  8. * The braided steel line for the external resovoir should point toward the rear of the car. (Note: before I called Tri-Point for clarification on another issue, I had already installed mine with them pointing towards the front. They said this was perfectly fine, but they usually install them towards the rear. I actually prefer the front, as it keeps the resouvoir away from the heat generated by the exhaust. You can always unbolt the bottom of the shock and rotate it the other way.)

  9. Put the top rubber washer over the shock rod. Position the rear strut tower brace and install the three nuts on top of the studs, but do not tighten. This will keep the shock from falling down while positioning the lower mounting bracket.

  10. Fasten the lower bracket of the shock into place with the bolt on the end of the anti-sway bar link. Torque down to the specs in the shop manual. Note: you may have to tighten the 1/2" nut at the top of the shock down to get it to go up enough so that the bottom can be moved into position.

  11. Once the lower end has been installed, finish tightening the three nuts on the studs. Add the two 1/2" washers and 1/2" nut to the shock rod, and torque down.

  12. Repeat for the other side.

  13. * Route the steel line for the external resouvoir through the suspension links in such a manner that it will not rub on anything or get pinched when the suspension moves.

    Installed Shock Resouvoir

  14. * Attach the external resouvoirs to the frame of the car using plastic zip ties. (Shown to the right.) Use at least three ties per side. Also zip tie the braided steel line to the frame of the car (but not tight enough to squeeze it). The line should not project past the center of the shock, i.e.- it should not stick out towards the tire. The resouvoir should be positioned so the filling valve is two inches or so away from the bushing for where the lower suspension arm mounts to the frame of the car.

  15. Complete the installation of the anti-sway bar by attaching the end links to the bar and tightening the nut. Then bolt the bar to the frame of the car. The bar should rotate in the bushings. If you tighten it too far it will not. The urethane bushings may be a little bigger than the stock ones, so you may need to add a washer or two between the mounting bracket and the frame. This should keep the bar loose enough in the bushings. One washer worked for me. Tighten down the positioning clamps on the bar.

  16. * Set the shock rebound adjuster on the external resouvoir to 3, and the compression adjuster at the top of the shock to full stiff minus 1/2 to 3/4 turns. Full stiff is where the nut is screwed all the way in (clockwise). Back it out to adjust. These settings are starting points - adjust for your style of driving.



FRONT SUSPENSION - DISASSEMBLY

The front turned out to be easier than the rear, maybe because I had some practice doing the rears first.

  1. Break loose but do not remove the lug nuts.

  2. Jack up the front of the car and set it on jackstands.

    Front Swaybar Comparison

  3. Finish loosening the lug nuts and remove the wheels.

  4. Remove the brake line from the shock. It is held in place by a clip that pulls out. Remove the ABS sensor.

  5. Remove the two bolts that attach the upper control arm to the frame of the car. It is not necessary to remove the last bolt attaching the arm to the hub assembly.

  6. Note: If you have problems with the bolts at the bottom of the shock and the anti-sway bar hitting the steering control arm, turn the steering wheel. At first I thought I was going to need to drop the control arm because some idiot at Mazda had put the bolts through the wrong way and then installed the control arm after that. Turns out the idiot (me) just needed to turn the steering wheel. If you center the steering wheel before you start you may not even run into this issue.

  7. Remove the front strut tower brace. The three bolts that attach are fastened to the studs on the top of the shock assembly and hold that unit in place.

  8. Unbolt the anti-sway bar end link from the bar itself before attempting to remove the bolt at the bottom of the shock. This will make it easier to get the bolt out of the bushing. (If you are going to replace the anti-sway bar, you might as well remove these at this point anyway.) Remove the bolt at the bottom of the shock.

  9. With the strut tower brace removed at the top, and the anti-sway bar end link bolt removed at the bottom, the shock is not free, and can be removed from the car.

  10. Once you have the springs/shocks out, use the spring compressor to disassemble them. The stock top rubber mount and rubber washers will be re-used.

    Front Shock Comparison



FRONT SUSPENSION - ASSEMBLY

  1. The best advice I could give you would be to loosely assemble everything before tightneing anything down. There will be a lot of adjustments in terms of alignment that will have to be made to get all the bolts and holes to line up.

  2. * This particularly applies to the anti-sway bar braces if you have the Tri-Point braces and the Racing Beat brace. You will be threading the bolt through 4 layers if you use both of these.

  3. * First position the Racing Beat brace with the bolts for the steering rack.

  4. * If you buy the optional Tri-Point anti-sway bar brace (they make this for MazdaComp), note that the two sides are different. This will become obvious when you try to bolt them in and they seem to be twisted too far up or down at the front. So position them first before tightening the bolts down.

  5. * Install the Tri-Point braces over the top of the Racing Beat one. (This means that the Racing Beat brace is sandwiched between the frame of the car and the Tri-Point brace.)

  6. After assembling the anti-sway bar, bolt it to the Tri-Point brace. Do not attach the end-links to the A-arm yet. The following pictures shows everything installed. The Racing Beat brace is the white one running laterally. The Tri-Point braces are the gold ones running longitudinally.

    Sway bar and braces installed

    The directions I got from Tri-point said to trim the rubber mount, but I found that it serves no useful function, and it squeaked against the new spring perch. I confirmed this with Tri-Point, and they said it should just be removed. In any event, it would not have needed to be trimmed like the rear one anyway, since the boot is a separate piece.

  7. * Drill out the two stock rubber washers on each shock with a 1/2" drill bit. These have extremely hard metal inside, so use a cobalt bit or other bit designed for this. A drill press helps a lot but is not absolutely necessary for this operation. Clean up the holes with the Dremel tool w/ sanding attachment or a rat tail file.

  8. Assemble the new shocks/springs, using the stock mount (with rubber donut removed) and lower rubber washer. Tighten the 1/2" nut at the top of the shock down to the torque listed in the shop manual. (WARNING: this is NOT the small nut that is part of the top of the shock - that is the compression adjustment. The compression adjustment nut has small holes in it.)

  9. * Use the bump stop that came with the Penskes, not the stock one. This is the large rubber piece on the shock rod (inside the spring).

  10. If you are replacing the anti-sway bars, assemble the new bar. Grease the urethane bushings with lithium grease. (I used Valvoline Synthetic.) Just grease the inside of the bushing, no need to do the outside where the bracket will sit. Urethane bushings will squeak really badly if you do not grease them. Install the urethane bushings on the bar and put the stock mounting brackets on the new urethane bushings. Install the locator clamps (but do not tighten yet). Put the new bar on the car, but do not bolt it into place yet.

  11. * I bought the optional Tri-Point anti-sway bar braces, so I do not use urethane bushings. Just grease the inside of the bushings that come with these. (Tri-Point said that even these do not need to be greased.)

  12. Optional step if you do not buy the Tri-Point anti-sway bar braces - add a grease fitting to the urethane anti-sway bar bushings. See the instructions above for the rear anti-sway bar.

  13. * The braided steel line for the external resovoir should point toward the front of the car.

  14. Position the lower end of the shock first. The directions said to use a punch and hammer to push the spacer in the lower control arm back out a little. This did not seem to work too well. It is just a pain to do.
  15. Position the top of the shock/spring by locating the three studs on the top rubber mount in the holes in the body. You will also have to position the top A-arm at the same time. This is kind of a pain also.

  16. Put the top rubber washer over the shock rod. Position the strut tower brace and install the three nuts on top of the studs, but do not tighten.

  17. Add the two 1/2" washers and 1/2" nut to the shock rod, and torque down.

  18. Repeat for the other side.

  19. Finish tightening everything down.

  20. Attach the anti-sway bar end links and tighten down.

  21. * Since the Penskes do not have the bracket for the brake line clip, zip tie it to the shock or other location where it will not be pinched, ripped out, or otherwise affected by the travel of the suspension. Be careful not to overtighten the tie or pinch the line with it.
  22. * Route the steel line for the external resouvoir through the suspension links in such a manner that it will not rub on anything or get pinched when the suspension moves.

  23. * Attach the external resouvoirs to the frame of the car using plastic zip ties. Use at least three ties per side. Also zip tie the braided steel line to the frame of the car (but not tight enough to squeeze it, just to keep it where you want it). The line should not project past the center of the shock, i.e.- it should not stick out towards the tire. I placed the resouvoir on the sides of the plastic panel underneath the engine.

  24. * Set the shock rebound adjuster on the external resouvoir to 5, and the compression adjuster at the top of the shock to full stiff minus 3/4 to 1 turns. Full stiff is where the nut is screwed all the way in (clockwise). Back it out to adjust. These settings are starting points - adjust for your style of driving.



POST ASSEMBLY

  1. Take the car for a short drive. Check the torque on all bolts/nuts.

  2. * Make sure the steel lines for the shock resouvoirs are not being pinched or binding. Make sure the resouvoirs are still positioned correctly by the zip ties.

  3. Get the car corner balanced and aligned. Alignment pecs posted here. This is more or less mandatory after installing coil-overs, and will make a world of difference. Make sure that the shop does it with you (or equivalent weight) in the driver's seat, and the amount of gas in the tank as you will be running with.

  4. At the same time as aligning and corner balancing, adjust the anti-sway bar to get rid of preload (this must also be done w/ your weight in the seat).

  5. You may also need to align the headlights since the car's height will more than likely change.

If you do not currently have a spring compressor, you have four options:

  1. Buy the compressor. I got mine for about $50 and it is way overkill for what it would take to do the job. It is basically two large bolts, probably about 5/8 threads, and two brackets per bolt that have u-bolts that slip around the spring coils. I think $50 is way too high for this - maybe $20 would be reasonable. There should be cheaper ones out there, especially if you buy mail order from a tool company.

  2. Buy the parts and make your own. The one I bought is probably about $15 worth of parts, but as a kit they get $50. I was in a hurry and didn't want to waste the time getting all the pieces.

  3. Take the used and new springs/shocks to an auto parts store and have them change them for you. I don't know how much this costs, but some places will do it for free if you buy the new parts from them. I chose to apply the cost of this towards the spring compressor since I am sure I will use it again at some point.

  4. You might also get lucky and be able to borrow a spring compressor from the auto parts store. Some places will loan them with a deposit.

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