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HOW TO: Urethane Suspension Install for the I4 GS/RS

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This is a how to on replacing your old worn out suspension bushings with a combo of Polyurethane and OEM Rubber. Both Prothane and Energy Suspension make kit’s for the 3G; I used a combo of the 2 brands to meet my needs, along with some OEM parts. The title says this is for the I4 but it can be used for the V6 as well, the only real difference is the rear motor mount. Also I did this on a 2003, there is a difference between the front control arms of the 2000 - Jan. 2001 models and the Feb. 2001 - 2005 models, so look out for that. Just compare the picture of mine to the picture of linlan's a few posts after this to tell the difference. I gave all my parts I used, the part number and hyperlinks to where I got them from, I included a ton of picture of what I did and how.

I hope this helps, just be patient and take your time.

Special thanks to Silvertune, Svenhoek and Chaveseclipse for helping me figure all this stuff out for you guys.

This install/how to will be in 3 parts, Motor Mounts, Front Control Arms with Front Sway Bar and Ball Joints, and Rear Control Arms with Rear Sway Bar, Ball Joints and Knuckles

But first the parts I used:

I used a combo of Energy Suspension and Prothane parts, you can however use just Prothane as they are the brand that has all of the bushings (Energy Suspension does not have motor mounts for the I4 or rear knuckle bushings for the 3G at all, but from what I was told the Prothane control arm bushings do not come with sleeves), Energy Suspension does have a front and rear motor mount kit that includes center cross member bushings for the V6, they are solid (Prothane front and rear are slotted).

Prothane Motor Mount Inserts - 4 Mount Set - 4Cyl Models, Part Number: 131904 from here: 4Cyl Motor Mounts

OEM 2.4L Manual Trans Rear Mount, Part Number: MR272202 (Prothane Motor Mount kit uses inserts that wedge into the OEM manual rear mount) from here: Rear Mounts

OEM Front Center Cross member Bushings; 4 x Part Number: MR311113 (bushing halves) and 2 x Part Number: MB303651 (bushing sleeves) from here: number 15 and 16

Energy Suspension Front Control Arm Bushings Mitsubishi Eclipse Feb. 01-05, Part Number: 5.3136 (note that the front bushings are different between the 2000 to Jan. 2001 and Feb. 2001 to 2005, this kit is for the after years, Prothane's kit is apparently for the 2000 to Jan. 2001 only but can be made to work) from here: Front Control Arm Bushings

Energy Suspension Front Sway Bar Bushings - 16mm, Part Number: 131106 from here: Front Sway Bar Bushings

Dorman Left and Right Control Arms with Ball Joints, Part Numbers: 520537 and 520538 (cost is just a little more than a new ball joint so why not?) from here: Rock Auto

ProSteer Front Tie Rod Ends with grease fittings from PepBoys

Energy Suspension Rear Control Arm Bushings, Part Number: 5.3128 from here: Rear Control Arm Bushings

3 x Prothane ECLIPSE (95-99) Polyurethane Knuckle Bushings, Part Number: 64185 (rear knuckle is the same for 2G and 3G, hence AWD 2G rear end swap) from here: Rear Knuckle Bushings

Dorman Rear Lateral Link with Ball Joints (A.K.A. Toe Control Arms), Part Numbers: 521527 and 521528 (Once again cost is just a little more than the ball joint so why not?) from here: Rock Auto

Tools you might want to consider:
-floor jacks
-jack stands
-breaker bar
-torque wrench
-metric sockets and wrenches
-BFH, rubber and metal (you'll find a few uses)
-pry bar (force motor mounts in place)
-drill with a cord (or a lot of drills with extra batteries, I used 2 with 2 batteries each)
-hole saw drill bit’s (cut out bushings) I used 2 3/4" - motor mounts, 1 1/4" - front and rear control arm bushings and 1" rear knuckle bushings
-90 degree drill bit elbow (passenger side upper knuckle bushing, fuel filler neck gets in the way)
-sawzall with a cord and a metal cutting blade (or a second one with extra batteries, I used 2 with 2 batteries each)
-flat head screw driver, metal chizzles and a hammer (bend out metal sleeve after cut)
-big vice (squeeze new bushings in)
-round metal file (to de-bur inside of bushing housings)
-Black and Decker mini electric hand saw with metal blade FTW!! (Specifically for the upper rear knuckle metal rings)
-DON'T FORGET THE LUBE, YOU'LL WANT PLENTY (I had a great experience with Liquid Wrench White Lithium Grease)
-Anti-seize (after fighting to get the bolts off, you'll see why)
-Second car to make a few trips to Ace Hardware or similar

You will want to get an alignment after you do the control arm and knuckle bushings, My alignment was slightly off after I did this install

Part 1: The Motor Mounts and Front Center Cross Member Bushings;

For this, you will want the front of your car on jack stands. You want to use a second jack to lift up the Trans/Engine to get the weight off the mounts. Be sure to engage your E-brake and put chucks under the rear tires.

For the front and rear mounts I found it easier to completely remove the Center Cross Member, 2 bolts in the front and 2 bolts in the rear and it will come right down, just remove the bolt through the front mount, a socket and wrench will do the trick. A breaker bar is recommended.

Front Center Cross member Bushings:

Since the cross member is off, now is the best easiest time to do this. The bushings just push in so pull them out, it really is that easy. Energy Suspension makes a poly bushing for these but they only come with the v6 motor mount kit, I used OEM parts instead.

mine was a PITA just due to the rust under my car:

Once the old ones are out, press the new ones in, one half from the top and the other half from the bottom. Then slide in the new or reused old sleeves. It will look like this when done:

Front Mount:

This is the Prothane front mount:

Once the center cross member is off, remove the 2 bolts holding the mount to the cross member. Note that the little hole in the mount is facing the front of the car; you want to put it back on that way. Check those bolts, mine were bent from the mount being bad and for reference they are M10/1.25 x 25mm

Once you have the mount off, put it in a vice and use a hole saw to cut out the middle.

Next you'll want to cut the rubber and inner metal ring, while not cutting the mount it’self. Once done, use a combo of screw drivers and chizzles to bend and hammer that thing out of there. (These are picture of the trans mount but it’s the same process)

Once out, clean the inside of the stock mount to remove all rubber and metal shavings. Then lube the hell out of the Prothane mount and inside of the metal housing. I used White Lithium Grease spray, it worked like a charm. Put them in a vice and use a screw driver to help guide the lip into the mount. Once in wipe off the extra grease and you’re done.

Now here is where you’re going to want to fix a problem. The Prothane bolt sleeve is about 1cm in diameter bigger than the bolt. You want to use a bolt sleeve to fill in that space. Ace Hardware has them, and what I used are 2 x 1/2" outer diameter x 3/8" inner diameter x 1" long and 2 x .656" outer diameter x 1/2" inner diameter x 1" long. (Silvertune used a ½” grade 8 bolt and nut, with one (1) .656” x ½” x 1” and one (1) .656” x ½” x 1.5” sleeves and drilled a ½” hole through the mount frame on the trans.) There's is still a little wobble but not a lot anymore. Take the mount and bolt to the store and find ones that will fit properly. Then would also be a good time to replace any busted or heavily rusted bolts you want. Here is what I'm talking about:

This is with the spacers mentioned above:

Now you want to put the mount back on the center cross member with little hole on the mount to the front. Bolt it down to torque specs. Then put the cross member back on the car and use a combo of the jack and pry bar to get the bolt into the mount, don't forget the sleeves, and tighten it to torque specs. (If you’re doing all of the mounts at once, save this step till the end)

This is what it will look like when it’s done:

Here are the factory torque specs for when putting the mount back on the car:

Rear Mount:

This is what the Prothane rear motor mount insert looks like:

It is supposed to be pressed into the stock rear mount, and NOT completely replace it. This is where I ran into the problem, the Prothane inserts only fit into the I4 manual rear mount, and there is a difference between the auto and manual rear mount. Manual mount is on the left, auto on the right:

The Prothane inserts will not fit into the auto mount, but can be pressed in by hand to the manual.

FYI: THE AUTO AND MANUAL MOUNTS ARE INTERCHANGEABLE :yesway: and the auto bolt fits through the manual mount, nice and tight so no sleeves are needed

For this mount you want the battery and tray completely removed and the engine supported with a jack. First you want to remve the through bolt holdinge the engine bracket to the mount.

Next you want to remove the 3 bolts that hold the mount to the k-member. 1 on the driver side and 2 on the passenger side. The one on the driver side and the front one on the passenger side you can get out with a socket and long extention. The back one on the passenger side I had to use a box wrench from under the car.

Once again I had a lot of rust to deal with so for reference these are 2 x m10/1.25x30mm bolts with a 10mm lock washer, I replaced all 3

Once the old mount is out, slide the new one in (or at this time slide your poly inserts into the old manual trans mount, easily done by hand on the manual style mount only) Be sure to line up the holes in the base of the mount to the holes in the k-member. Once lined up have somebody adjust the engine with the jack while you slide the through bolt through the bracket and mount. Hand tighten. Put the three bolts through the base to the crossmember and hand tighten. Once the car is back on the ground you can tighten everything to torque.

Sorry no pics but its simple enough to figure out.

Here are the factory torque specs:

Trans Mount:

The trans mount is located on the driver side, under the metal battery tray. Remove the battery and a total of 6 bolts hold the tray down. This one was just annoying to work on IMO.

This one is the Prothane trans mount, it’s the smaller of the 2 2-peice mounts:

The trans mount is held to the trans by 4 nuts on the base of the mount, and one bolt through the mount holding it to the frame. Remove all of these. Just to note, some penetrating oil might help you, but for me the nuts were fused to the studs and 3 of 4 studs came out with the nut not moving at all. Once all the bolts are removed, use a combination of pulling up and toward the engine on the mount while someone SLOWLY lowers the trans to get the mount to clear the studs. This need done because there is a ledge that helps support the battery tray over top of the mount that gives it to little clearance. You should be able to see what I'm talking about.

Now, to remove the old bushing do the same as you do for the front mount. Hole saw and a sawzall to cut out some of the bushing and cut down through the inner metal ring, but not the mount itself. Then once again a combo of a screwdriver, metal chizzle and hammer to bend/bang the inner ring out.

Once the inner ring is out, clean the surface of the mount and new Prothane insert. Then White Lithium Grease the inside of the mount and insert. (I did not use grease on this one and it was a bitch, use lube.) Put the two sides of the insert, without the metal sleeve and the mount into the vice, line it up and then squeeze till it's in. Once the insert is in, line up the metal sleeve with the mounting hole and use the vice to press that in. (I learned from experience it is just easier to put the metal sleeve in after the mount insert is in the mount. So I don't have picture for this, but I do in the front control arm section, it’s the same principle)

To put the mount back, line up the base with the studs as best you can. I used a combo of a pry bar and rubber mallet to force the thing into its location. Tighten the mount to the trans but not to torque specs yet. Use the jack to lift the trans as well as a pry bar to line the hole up for the frame to go through the mount. This bolt does not need sleeved as it fits perfectly. Once in you can tighten that bolt to torque specs, for the 4 trans bolts you need to wait for the car to be back on the ground. Here is how it looks when done:

And this is the factory service manual torque specs for the trans mount

Engine Mount:

Here is the Prothane engine mount, it’s the bigger of the 2 2-piece mounts:

For this you will want to move the floor jack from the trans side to the engine side. Lift up on the engine to get the weight off of the mount. You will want to remove the coolant reservoir tank (remove the hose from the radiator and just lift up on the tank) then remove its mounting frame (2 bolts at the base). The engine mount is obviously on the passenger side.

2 nuts and 1 bolt hold the mount to the engine and one bolt goes through it to hold it to the frame. Remove all of these and just lift up and out. Follow the exact same steps you did for the trans mount, hole saw, followed by sawzall, followed by bending/banging the inner ring out. Note that there is a disgusting, sticky black fluid in the engine mount rubber that will fly out kind of like blood would if you took a hole saw to a person, it sucks but just be ready for it, it’s going to get everywhere.

Once the mount and ring are out, clean it, apply grease to the new insert and press in with a vice. Line up the flat edges of the insert with where the metal on the mount flares out to bolt to the engine. You'll see what I'm talking about, it’s just for clearance.

To put the new mount in just line it up and use a rubber mallet to force it in its location. Bolt it to the engine but not to torque specs (same thing as the trans mount, you need to wait till the car is on the ground to torque these 3; 2 nuts 1 bolt). Do the same as you did for the trans side and slowly lower the engine jack till the hole lines up with the frame mounting hole. This bolt you can torque to specification. Don't forget to put the coolant tank back in!!! Here is what it looks like when done:

Here are the engine mount torque specs:

Once all the mounts are in, put the center cross member back on and tighten to torque. Then put the front mount bolt through (it should be sleeved) and tighten to torque. Lower the engine jack and remove it, then lower the car. Ensure all bolts are to torque specifications (mainly the trans and engine mounts). Put the battery tray back in and hook the battery backup. You are now done with the motor mount inserts.

Provided Prothane instructions:

Motor Mount Review:

Since the mounts are in I will say there is more vibration in the cabin, but it is not the most terrible thing on earth. I do hear my dash vibrating, which is most likely because it is cracked so the thing is rattling against itself. The sleeves in the front mount do rattle a little on takeoff but that is better than the 1cm of play that would be there without the spacers. There is no wheel hop at all which is :yesway:. For reference my car idles at about 600 RPM's and is an automatic. The vibration in park and neutral is barely more than what it was with just my exhaust, and is most noticeable in drive.

Part 2: The Front Bushings:

Front Control Arms

First thing you want to do is remove your front control arms, one at a time. It's not too bad, but the ball joint can be a PITA. Start by removing the bolt/nut from the ball joint at the front knuckle, it is easier if you turn the steering wheel to the extreme right or left. I rounded the nut and bolt due to rust, be careful but for reference the bolt is m12.

Next remove the 2 bolts from the rear bushing (bigger one) and the 1 bolt from the front bushing.

Pull the arm down and rotate to the side so you can beat the hell out of it with a hammer while prying the ball joint housing open to get the ball joint out (Use force, it’s in there). Do this and the arm is off. Picture below is why I replaced mine, and the new one ready to go in, so shiny :lol:

When the control arm is off, you want to do the front sway bar bushing if you have it

Remove the 2 bolts that hold the bracket on, take off the old sway bar bushing and then put the new one on. Be sure to lube the inside of the bushing. Put the the bracket back on (longer edge to the top) and torque to specs. Picture is where it’s located, sorry but no picture of actually doing it, but I promise it's not hard.

Now you want to put the new bushings in.

First is the rear bushing (the bigger one), it’s just a little harder to do. Remove the rear bushing and housing completely and put it in a vice. Use a hole saw to cut out the middle so a sawzall will fit. Use the sawzall to cut through the inner ring but not the bushing housing itself. I found it easier to cut through in 2 spots next to each other (see picture). Use a hammer, screw driver and chizzle to bang the ring out just like I mentioned in the motor mount section.

Once the old bushing and ring is out, clean off the inside of the housing and the new insert. Energy Suspension has a graduated side that should be pushed in first, it just makes it easier. This is the side that is slanted from small to big on the lip. Add the supplied pre-lube to that slanted edge and the lip of the bushing, put it in a vice and squeeze. Use a screw driver to help guide the lip in. Once in wipe off the excess lube because that stuff is sticky and will cause a mess.

You’ll do this all over again for the other side. When done place them off the side, just make sure you can see the engraving on it for which one is left and which is right.

Now the front bushing (little one). Use wood to help clamp the entire control arm in the vice. Use a hole saw to remove the stock bushing. This one does not have a metal ring so once the bushing is out you are good to go :yesway:

Once the old bushing is out, clean the inside of the arm and the new bushing. Add just a little lube to the new bushing (Energy Suspension is 2 pieces and can press in by hand). Push the new bushing in place without the metal sleeve in it. Once the bushing is in, line up the sleeve with the hole and use a vice to press it in.

Just repeat that process for the other arm and you are done. Here is what they will look like:

Now to put the control arms back on.

Torque the rear bushing while the arm is off the car, you can't get a torque wrench to fit when the arm is on the car. Put the 2 bolts back into the rear bushing and the one into the front (you want that bolt half through so you can get the arm in place). Use a rubber hammer to help line things up. (No picture but it’s not hard) Once the bolts are in, rotate the arm up to line up the ball joint. I found it easiest to use a floor jack to pop the ball joint in. Put the bolt through. Once done tighten everything to torque specs.

I went ahead and replaced the tie rod ends while I was down there, here is the new one:

Here is the new arm and bushings when done:

Provided Instructions:

Factory torque specs:

Part 3: The Rear Bushings:

Rear Control Arms and Knuckles

Stand by for a lot of rust. This is where I ran into all of my headaches.

I started with the trailing arm, to access it, you need to remove the rubber grommet from the rear wheel well.

Remove the bolt and nut from the car frame, and then from the knuckle. For the trailing arm bushing it is the repetitive drill, cut, hammer, press (tapered edge in with lube, sleeve after bushing):

For the Knuckle it’s the same thing for all 6 bushings. It’s just a PITA due to clearance issues because You probably want to leave it on your car, I did. Drill, cut, hammer and press (use a c-clamp, lube it up and put the sleeve in after the bushing)

Put the arm back on because you want as much support on the knuckle as possible while banging out the metal rings. Use a hammer to help line everything up.

Next I did the lower control arm. First remove the sway bar end link, then remove the bolt through the cross member and the one through the knuckle. Same steps as above for the arm and knuckle bushings. Here is what I ran into:

Put the lower control arm back on, use a hammer to line it up and replace any broken bolts.

Next I did upper control arm. I learned at this point that rust can fuse the bolt to the bushing so that the bolt doesn’t spin, but the rubber does. I had to remove the frame brackets and cut the bushing bolts off.

Once the bolts were cut the brackets needed pried off, then pressed to be strait again (damn my dad ended up in a lot of pictures :lol: )

Because the bolt was still in the bushing I couldn't use the standard hole saw and improvised. I used a 14mm socket, a vise and 2 pipe wrenches to McGuiver that thing out:

This is what I mean the bolt was fused to the bushing:

Once the bushing is out it’s the typical cut, hammer, press, in the same pattern as mentioned several times (just press in 1 half of the bushing at a time for ease, then the sleeve, repeat 3 more times):

I obviously needed new bolts so:

And when done it looks like this:

The upper knuckle was a b**ch, no other way to say it. I had to use a hack saw to cut it (found out a mini electric saw with a metal blade works great the second time around), sawzall wouldn't fit. On the passenger side the fuel filler neck gives even less clearance so I had to use a regular drill bit to cut it out hole by hole (can also get a 90 degree drill bit adapter and use the hole saw)

Take your time to bang out the sleeve; someone should brace the knuckle because it will move all over without the upper control arm in. Put the new bushing in with a c-clamp like all the other knuckle bushings. Put the upper control arm back on. Use a jack to help lift up the rear knuckle and a hammer to line it all up.

Tighten everything up to torque, there is a lot so don’t forget anything. You should have lubed all the sleeves/bolts and used anti-seize. Here are picture of when done, please pardon the dirt/dust. This project took a while and pissed me off enough to not care what the car looked like for a bit.

Provided instructions:

Rear Ball Joints (new toe control arms)

As pictured, you can see that instead of replacing the ball joints, I just went ahead and replaced the entire rear toe arm with Dorman OEM replacement parts. Glad I went this way because as with the rest of the bolts thus far, they were rusted to hell. I had to cut the old arms out because the rust fused everything together. The picture below is the amount of rust on these sleeves:

First thing I did was use my sawzall and cut through the sleeve and bolt on both sides and loosened the ball joint nut to remove the arm.

Once out I used a combo of a big hammer, metal punch, vice grips, wrenches and pipe wrenches to loosen and wiggle the left over sleeve off of the bolt. It took a lot of umph and PB Blaster to do.

Once everything was out I covered the new toe adjustment bolt with anti-seize (By the way bolt p/n is MB911314 and the adjustment plate for the other side p/n is MB911283)

Just put the ball joint through the knuckle and tighten the nut, then the toe bolt through the cross member and sleeve, put on the adjustment washer, lock washer and nut. Tighten everything to torque and then get an alignment. Here is everything when done:

Factory specs you should consider:

Control Arm and Knuckle Bushing Review:

I have noticed the car is stiffer and rebounds to everything. No squeaking which I have read other members have ran into. For reference I have coilovers which already causes the car to rebound. I have front and rear strut bars, a front lower tie bar and ST rear sway bar. I can feel every imperfection in the road, but that was the goal: to stiffen the ride. They don't make for comfort but do help improve handling.
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