Installing KYB Struts on a ’98 RivieraSuspensions on larger luxury cars like the Riviera can be a bit on the soft side, even new. After 100k miles or so, they can get a little
too soft; suspension failure can creep up very slowly during that time. It may not be that noticeable, but if the car is bouncing all over the road, vibrates abnormally over bumps, makes squeaking noises, or rolls excessively in the turns, it’s probably time to think about fixing the suspension. The front struts are a good place to start.
KYB strutsThe factory struts, made by Macpherson for GM, are adequate, but another option is the Japanese made GR-2 by KYB (originally “Kayaba Manufacturing”). The GR-2 is a gas strut that’s a little firmer than the OEM model. KYB's intent with the GR-2 is to improve performance over the original design, but not to change the handling of the car in a drastic way. KYB makes other high-performance struts for the purpose of creating very firm road holding, but unfortunately not for the Riviera. Nevertheless, if your OEM struts are on their last leg, even the basic GR-2s will seem like a major upgrade.
‘95-‘99 Riviera Suspension ChangesThe Riviera’s suspension geometry was changed from ’96 to ’97, and then again in ’98. The KYB part # for the ’98 model struts is: KYB-335037. For ’95-’96 the part # is: KYB-236007. There is no known part # for the '97 year. ’99 models should be the same as ’98, but there could be slight differences, so do the research before buying.
Where to buy?Summit Racing seems to have the best deal on GR-2 struts. They also sell the strut mount/bearing kit, which you’ll want to buy along with the struts. The GR-2s (KYB-335037) are $69.88 each, and the mount kits (KYB-SM5276) are $51.39 each at the time of this write-up. You’ll need two struts and two kits for the job, which will total around $270 including tax and shipping.
Tools needed for the job:You will need:
- PB Blaster lubricating penetrant
- 3/8” & 1/2” ratchets
- 3/4”, 10 mm, 15 mm, & 24 mm sockets (deep well recommended)
- 24 mm wrench
- 6 mm Allen key
- torque wrenches rated to 13, 35, & 136 lb-ft
- hammer
- flathead screw driver
- spring compressor (can be borrowed for $50 deposit at most auto parts stores)
- several 2x6” wood blocks
- hydraulic jack
- (2) jack stand supports
It’s also a good idea to have a spotlight and extension cord around in case the project runs longer than expected, and a friend with a car can come in handy, as your ride will be completely out of commission during the install. And while a 6-pack of your favorite alcoholic beverage would normally be recommended, it is better to pass on that for this job. You want to be double sure to have all of your faculties when working around compressed springs.
Installing the struts…The job should take about 4 hours, but allow 6. A good way to work is to do everything in tandem fashion between the driver and passenger sides. For each step, when you do something to one side, do it on the other as well - assume each step represents doing both sides of the car. This should make things go much more smoothly, you won’t forget any steps along the way, and there will be less chance of you only getting one strut finished. Because of this, the pictures below are taken from both the left and right sides of the car, so if something looks reversed, you know why.
STEP 1: Park the car on a level surface and engage the parking brake. Carefully remove the front center caps and break loose all front wheel nuts.
STEP 2: Using a 15 mm socket, remove the 3 strut mount bolts from the top of the strut. The bolts are located under the hood and above the wheels. At this time, do not remove the covered nut at the center of the strut. Note: '96 and earlier models have 3 nuts on top instead of bolts.
STEP 3: Jack up the front end of the car and support with jack stands. You only need to raise the car enough so that the wheels can be removed. Although it’s not a good idea to raise the car using any location other than the recommended jack points, it’s okay to support the vehicle from the cradle (frame near the control arms) if you spread out the load so that nothing gets bent. Using a wooden block between the jack stand and the car is one way of doing this. Be sure to let the control arms hang free.
STEP 4: Remove the wheel nuts and front wheels.
STEP 5: Disconnect the ABS speed sensor connector and, using a flathead driver, remove the clip from the bracket as indicated below: Spray the two large knuckle bolts and nuts with PB Blaster. Also spray the two small screws holding the brake and ABS sensor lines to the strut.
STEP 6: Using a 10 mm socket, remove the bolts securing the brake line and ABS speed sensor brackets to the strut.
STEP 7: Insert blocks of wood under the brake rotors to support the steering knuckle. This is for when the knuckle bolts are removed, so it won't won’t fall under its weight. If you don’t do this, you risk damaging a ball joint or drive axle.
STEP 8: Remove the knuckle nuts with a 24 mm socket. These are torqued on pretty well, so might require some force to break loose. A strong arm or an air impact wrench may come in handy here.
STEP 9: Keeping the knuckle nuts threaded onto the bolt, unscrew them out to the very end, then use a hammer to pound the knuckle bolts out by tapping the nuts. When you've pounded them out, remove the nuts, and the bolts should slide right out. Note: the knuckle bolts on the '98 are splined into the knuckle and WILL NOT TURN. If you try to torque on them, you will break either the knuckle, the bolts, the splines, or the tool you are using. Note: bolts on '96 and earlier models are threaded, not splined, so you'll need to turn them out (could GM try any harder to confuse us? No, this small detail isn't mentioned in the shop manual).
STEP 10: Remove the old strut and spring assemblies. Place them on something other than the ground so the coils aren’t damaged – remember, you’ll be putting those back on the car.
STEP 11: Now for the fun part - take the spring compressor and secure each half to a side of the spring. You’ll find that the strut, mount plates, and insulators will get in the way, so try to get each half as close to 180º apart as you can. Take care to avoid damaging the rubber insulators, as they will get reused. Using a ratchet or air wrench (recommended), tighten the tool to compress the coil. Be sure to do this evenly, switching frequently from one side to the other (you don’t want the spring bending like a slinky). A third hand may be helpful to hold the assembly as you compress the coil. Stop compressing once the large washer under the nut becomes loose at the top end of the assembly.
CAUTION: UNDERSTAND THE COIL IS UNDER EXTREME COMPRESSION. ALWAYS WEAR EYE PROTECTION AND CONSTANTLY OBSERVE THE SPRING COMPRESSOR TOOL TO BE SURE IT ISN’T SLIPPING OFF THE COIL OR MALFUCTIONING IN ANY WAY. ALWAYS POSITION YOURSELF, OTHERS, AND ANYTHING OF IMPORTANCE AWAY FROM THE DIRECTIONAL AXIS OF THE COIL. THINK OF COMPRESSING A SPRING AS SIMILAR TO COCKING A BIDIRECTIONAL CANNON. RESPECT IT AND BE SAFE!STEP 12: With the spring still compressed, remove the rubber dust cover and unscrew the nut from the top of the strut. You’ll need to use a 6 mm Allen key and a 24 mm wrench for this. Once off, remove the metal washer, strut mount/bearing, rubber ring & spring seat, strut, rubber bumper, and shield. Discard all of these parts accept for the shield, rubber bumper, spring seat, metal washer, and dust cover. Do not discard the rubber spring insulators. Try to leave the upper one on the end of the coil if possible (unless replacing). The lower one will probably come off with the strut. The insulators will hold the imprint of the spring, the strut, and the spring seat so that spring realignment will be much easier when installing the new strut. Keep passenger and driver side insulators with their corresponding springs and seats. See the photo and diagram below. The spring seat and rubber ring are not shown in the photo, and the ring is not in the diagram, but it is included in the kit and is yellow/black in color.
STEP 13: With the spring still compressed, transfer the specified components from the old struts to the new ones: reused parts include spring insulators, shield, rubber bumper, spring seat, metal washer, and dust cover. Replace the mount/bearing and rubber ring with the new ones in the kit. Make sure to reassemble everything with the spring and new strut exactly the way it came off. Take note of how the left and right side mounts are in relation to the spring seat, and use the spring insulators to guide you in positioning the spring, strut, and spring seat. A new nut comes with the new KYB strut – be sure to use it, as the threads are different from the OEM version. If you’re using the correct nut, and it won’t go on, you may need to tighten the spring compressor a little to expose more thread. Here’s a picture comparing the old and new struts before reassembly:
STEP 14: After every component is in place, and the nut is on the strut, you can release the coil’s compression by loosening the spring compressor tool until it can be removed. Below are the two assemblies ready to go back on the car. Wiping the shield clean on the driver side assembly is one way to keep from mixing them up.
STEP 15: Reinstall the new assembly in place, aligning the two “teets” into their holes at the top. Thread one of the strut mount bolts into the top to support the strut while you align the two knuckle bolts at the bottom. It may help to have a second person up top to help you do this. Note: '96 and earlier models have 3 studs built into the strut that recieve nuts up top. Same idea, different method. Once the knuckle bolts are aligned, tap them in with a hammer:
STEP 16: Thread the knuckle nuts onto the bolts and torque to 136 lb-ft. Reinstall the remaining 2 strut mount bolts on top. You may need to pry the strut with a screw driver or ratchet handle to get the holes to line up. Tighten the mount bolts to 35 lb-ft. Reinstall the brake and ABS sensor lines and tighten the screws to 13 lb-ft. Reattach the ABS speed sensor clip and plug in the connector.
STEP 17: Replace the wheels and lower the vehicle. Torque wheel nuts to 100 lb-ft and replace caps.
STEP 18: With the weight of the car now compressing the springs, the nut on top of each strut will probably be loose. Pop the hood and tighten each nut so that the washer and strut cannot move. Don’t forget to put the rubber dust covers back on when you're done!
STEP 19: You should have a front-end alignment done as soon as possible. It is probable that replacing the struts will throw off the suspension geometry a bit, so get it taken care of prompty and your tires will thank you. Most dealerships charge about $65 for this service.
Enjoy the new ride!!!