Write-Up: 1996 to 1998 Front Suspension Swap w/F-Body Brakes

albertj wrote:

For those knuckles, it would be a little fiddly but I would weld steel plate onto the strut's mounting flanges, and not modify the knuckle at all.  Then I'd drill/grind holes in those flanges as needed.  I would consider making the hole a little oblong in the appropriate direction in order to allow a little adjustment, maybe 1/8" or so. Not sure if the oldstyle strut would work with all the other changes.

I made the new struts work. Even though I have access to a welder I'm not to sure about welding ears onto the old ones.

Welp, after 6 flesh wounds and multiple bruises I did it. I'm now the 4th(?) person to convert to a 98 style front end. Springs and struts work beautifully. Old struts wouldn't go back up after being compressed. Front end feels nice and tight for the 2 minutes that I got to drive.

Unfortunately, I need to rebleed the brakes. I ran out of fluid otherwise I would have it done by now. The pedal goes to the floor and the car keeps going. Not good. They initially worked when pulling out of my driveway but then the pedal gave way. Fluid level did not change from when I left and got back so there's probably just a bunch of air in the line.

The car is also a little creaky when turning but I blame reusing the strut top mounts and tie rod ends.

matt270avian wrote:

albertj wrote:

For those knuckles, it would be a little fiddly but I would weld steel plate onto the strut's mounting flanges, and not modify the knuckle at all.  Then I'd drill/grind holes in those flanges as needed.  I would consider making the hole a little oblong in the appropriate direction in order to allow a little adjustment, maybe 1/8" or so. Not sure if the oldstyle strut would work with all the other changes.

I made the new struts work. Even though I have access to a welder I'm not to sure about welding ears onto the old ones.

Yep this is one of those things that is easier to show than to tell. Basically grind the paint off the outsides of the flanges, weld on flats, grind to shape, drill/grind desired holes. The old flanges would stay in place, they'd have 2 layers when done and would be stiffer than stock although I doubt it'd be noticeable.

Good job on the conversion and nice pictures.

Albert

Rebled the brakes and fixed the calipers (I had them on the wrong sides). After that they worked AMAZINGLY. Honestly, how have you '97+ people not done this yet? You have it so much easier than us 95-96 guys. Granted you all stay with the same size rotor but still.

Your bleeders were pointed down? Hard to get the air out, right?

AA wrote:

Your bleeders were pointed down? Hard to get the air out, right?

Exactly. You figure it out the hard way too?

Nope, but I know that set-up would not work!

Alright, now that I have everything figured out I suppose it's time to do a nice write up.

Materials Needed/Recommended:

97-99 Front Rotors.
98-02 F-Body Calipers.
98-02 F-Body Brake Pads.
97-99 Steering knuckles and caliper bracket bolts - These can also be found on 97-99 Aurora's and 98-? Seville's.
97-99 Struts - Strut top mounts are optional. I reused my old ones because the new ones would require making some new holes. You CAN NOT reuse your old struts without modification.
97-99 Springs (Optional) - If you use these springs you must use new struts. If you reuse your existing springs you must reuse or get new 95/96 struts and modify them. 97-99 struts WILL NOT WORK WITH 95/96 SPRINGS. You can reuse the 95/96 strut top mounts. You can also take this time to upgrade to F41 or FE3 springs found on the Park Avenue and the Seville STS. See the F41 upgrade thread for more info.
97-99 Hubs and bolts - 95/96 Hubs use a different mounting technique.
Camber Bolts (Optional) - These are a good way to get the alignment you want. They're cheap and work great.
Caliper Paint (Optional) - When going to all this hard work why not clean up your parts and make them look better than new?
Brake Fluid - Get the 2 of the big bottles of Dot 4 or your preferred fluid.
Extended stainless steel brake lines - The stock lines will not reach so you need extended ones.
PB Blaster - 2 cans to be safe. I didn't even fully use 1.
Anti-Seize Grease - You don't need a lot. 2 Small packets will do.
Your preferred grease for ball joints/tie rod ends.
Tie Rod Ends (Optional) - Another "While you're in there" thing.
Ball Joints (Optional) - Another "While you're in there" thing.
Cotter Pins - Should be supplied with Ball Joints and Tie Rod Ends. Regardless try to have a handful of extras.

Your best bet strut wise is to use 97 springs/struts/top mounts/everything else because the top mounts on 97s work on 95/96, but the struts have the correct knuckle mounts for 97-99.

Tools Needed

Torque Wrench.
3/8" Drive Sockets/Ratchets in METRIC.
1/2" Drive Sockets/Ratchets in METRIC.
Breaker Bar (Optional, I did not need one).
Impact Gun (Optional, it helps with working with the struts).
Air Chisel (Optional) - If you're doing ball joints you will need this to get the old rivets off. May also help with removing the axles.
BFH - The axles can be stubborn. A BFH comes in handy more than you would think.
Combination Wrenches in METRIC.
Shop Manual (Optional) - Helps to give you guidance and torque specs.
Flat Blade Screwdrivers
Wire Cutters
Needle Nose Pliers
Spring Compressors
Vacuum Brake Bleeder (Optional) - These calipers are larger making conventional bleeding more difficult and less effective.
Adjustable Wrench (Optional) - I needed one because I did not have 2 of the same size socket for the camber bolts. You'll need one about the length of your forearm.
Jack/Jack Stands
Pickle Fork
Allen Wrenches/Sockets
Drip Pan
Zip Ties
14x2mm Tap.
A Good Mechanically Inclined Friend

How To:

Every day for a week prior to doing this job soak the axle/axle nut in PB. I did mine when I left for work and when I got home from work. The axles like to seize to the hubs. While you're doing this tap out the caliper bracket mounting bolts with the 14x2mm tap so that the bolts match those of the knuckle. You can instead use a 12mm to 14mm sleeve but some claim that they cause the bolts to loosen. Use your best judgement here.

Work evenly on both sides. That way if something gets stuck on one side you won't have the other side completed and have everything uneven.

With the car still on the ground break the axle nuts and lug nuts loose. Do NOT remove them at this time.

Jack the car up and securely support it.

Remove lug nuts and rims.

Remove old calipers and rotors. Start off by removing the brake line from the caliper. Have your drip pan ready to catch the brake fluid that will leak out. After that use an Allen socket to remove the caliper mounting bolts. These will not come out of the caliper. If the caliper does not slide off easily you can stick a flat blade screwdriver into the rotor vents to pry it off. The rotor will just pull off once you have the caliper off.

Remove old brake lines and install new ones. With the rotor and caliper out of the way you will have more room to work now. You can choose to wait until reinstallation of the new rotor/caliper to do this step. With one wrench holding the nut on the hard brake line you can use another wrench to loosen the nut on the rubber line. Be VERY CAREFUL as these nuts are soft and strip easily. Installation is a reversal of the removal. Be sure to plug the end of the lines and watch the master cylinder to make sure that there is still fluid in it at all times. Letting it go dry SUCKS.

Unplug ABS connector and remove the bracket attached to the strut.

Loosen the axle nuts to the point where they are flush with the end of the axles. Start smacking them with the BFH and/or air chisel. If you can push the axles in by hand you do not need to hit them any more. Remove the nuts once the axles are broken free. You will NOT be able to completely separate the axles from the hubs at this time.

Using a hex head socket remove the bolts holding the hub onto the knuckle. There are 3 holes in the hubs but only 1 of them is big enough to remove the bolt. Just spin the hub every time you need to remove the next bolt. You can only spin the hubs with the car in neutral, or if both tires are in the air you can do it with the car in park. The hub should slide out at this point but if it does not do not worry.

Remove the camber bolts. Have one wrench on either side so that you can hold one of them to prevent the bolt from spinning while loosening the nut. Start with the upper ones. Once the nut is completely removed you can smack the bolt through the end. If the bolt is stuck do not worry.

Remove tie rod ends. This is where the pickle fork and BFH come into play. There is a cotter pin on the nut that will likely be stubborn and covered in grease. With the nut removed stick the pickle fork between the tie rod end and the steering knuckle and start smacking it with the hammer until the tie rod pops out.

Separate the knuckle from the ball joint. With the tie rod ends removed you can freely turn the knuckle to get access to the nut and cotter pin. With the nut removed stick the pickle fork between the ball joint and the steering knuckle and start smacking it with the hammer until it pops loose.

Remove the knuckle. If the hub was stuck to the knuckle this might be a little harder. Same goes with if one of the camber bolts is stuck in it. Just keep pulling on it and wiggling it until it comes out.

At this time you can replace your ball joints and tie rod ends if you chose to do so. There will be no better time than right now.

Remove the 3 nuts holding the strut to the strut tower. Be careful not to let it drop on your foot. This is where a friend could come in handy to hold the strut while you loosen the nuts. DO NOT remove the big center nut at this time.

With the strut out you can compress the springs. A vice could come in handy to hold the strut and to keep it from spinning. Use good judgement here because this can be potentially lethal if you're not careful. Watch the compressor to make sure it is not slipping off the spring. Use 1 compressor on either side and tighten each side equally. I did 20 turns with the wrench on either side before switching sides. Start out with 10 on the first side and then 20 on the other. This way you're only giving 10 turns per side (make sense?). Keep going until the top of the spring is not seated with the top mount.

Disassemble/reassemble your struts. With the spring compressed you can remove the center nut. An impact gun is nice here because you can just zip it off without the strut spinning too much. If you try to use a ratchet the strut will probably spin and cause problems. Everything might take a bit of force to get off. Transfer everything over to the new struts in this order. Bottom rubber spring seat, dust boots, springs, top mounts. With the spring still compressed tighten the center nut on the new strut. Make sure everything is centered and then slowly decompress the spring.

Install the new struts. This is where your friend can come in handy again because aligning the top can be difficult. Have one person hold the strut while the other lines it up and gets some nuts on it. At this time you should loosen your sway bar end links as much as possible (or even remove them). This will allow the lower control arm to drop lower and make putting the knuckle into the strut a million times easier. It can still be done with the end links fully tightened but it will be a pain in the ass. Leave the nuts as loose as possible for the next step.

Install the new knuckles. Life will be easier if you have the hubs installed on the knuckles before proceeding. Start by putting in the ball joints and the axles. Next align the camber bolts. A flat blade screwdriver can come in handy here. Start out by pulling/pushing/turning everything until the bottom hole is visible through the strut's bottom hole. Stick the screwdriver in and use it to pry everything until the top hole is lined up. Stick the top camber bolt in and smack it through with a hammer. A friend can also come in handy here because one person can pry while the other sticks the bolt through. With the top bolt in the bottom one should go in with minimal hassle. Tighten the camber bolts/nuts and the strut top nuts. Put the axle nuts back on and get them snug. Install the tie rod end and tighten. Lastly tighten the nut onto the ball joint. DO NOT forget cotter pins for the tie rod ends and ball joints.

Now that the hard part is done it's just a simple brake job. Make sure everything is nice and clean for this. Install the rotor and secure it with 2 or 3 lug nuts. Install the caliper bracket and tighten it. Install the new pads. The pad with the tab sticking out goes on the OUTSIDE of the rotor. Make sure you have the metal things installed and greased properly. Slip the caliper over the whole assembly with the bleeder screws facing UP. The calipers can be installed on either side but with the bleeder screws facing down you will not be able to get a proper bleed. Tighten the 2 caliper bolts that go into the pins. Sometimes these pins like to get stuck to the caliper bolts. Use a vice grip or wrench to hold them while loosening or tightening the caliper bolts. Install the brake lines onto the calipers. Bleed your brakes. Zip tie the brake lines out of the way so they do not rub on the tires.

Reinstall your rims/tires and lower the car back on the ground. Torque everything down INCLUDING the axle nuts. Yay, you're done (hopefully). Go for a test drive and take it slow. Don't forget that we just had the whole front end of the car apart here. Brake nice and slowly and corner nice and slowly until you're confident everything checks out. You will need an alignment done.

Good write-up. What pads are you using, Matt?

AA wrote:

Good write-up. What pads are you using, Matt?

Just some cheap garbage ones for now. I'm waiting for my rears to run out because when they do the fronts should be done too. Then it's Hawk HPS's all the way around.

Edited the write up. Basically I pointed out that you CAN NOT use 95/96 springs on 97+ struts. The springs are of different design. The top mounts off of 95/96 can still be reused. The bottom isolator must be from 97+ as well. I picked up some springs off of a Park Avenue today. Not sure if they're F41 but I needed them today and I don't really want the front end any tighter.

matt270avian wrote:

97-99 Struts - Strut top mounts are optional. I reused my old ones because the new ones would require making some new holes. You CAN NOT reuse your old struts without modification.
97-99 Springs (Optional) - If you use these springs you must use new struts. If you reuse your existing springs you must reuse or get new 95/96 struts and modify them. 97-99 struts WILL NOT WORK WITH 95/96 SPRINGS. You can reuse the 95/96 strut top mounts.

Your best bet strut wise is to use 97 springs/struts/top mounts/everything else because the top mounts on 97s work on 95/96, but the struts have the correct knuckle mounts for 97-99.

So, I got a bit confused about the struts. Since I have a mine lowered I'd rather not mess with it if I don't have to. What exactly needs altered the strut to knuckle mounting holes? My apologies if I missed it.

The spacing on 97+ struts where they mount to the knuckle is different than 95/96 struts. You just need to bore out the holes on 95/96 struts to make them work, OR (this is a much better option IMO) you can get 97 struts because 95-97 all used the same springs, but the 97 struts have the correct mounting holes for the 97-99 knuckles. The problem with boring out the holes is that you could permanently ruin the camber if you don't do it perfectly.

I did a quick cross reference on rockauto and it seems the 95-96 use the same spring but the 97 is different.

Coil Springs:
95-96 Aurora/Riv - ACDELCO Part # 45H0354
97 Riv                 - ACDELCO Part # 45H2107
97 Aurora            - ACDELCO Part # 45H0286

Struts:
95-96 Aurora/Riv  - ACDELCO Part # 503353
97 Aurora/Riv       - ACDELCO Part # 503382

Moog specs show a difference in spring rate, load rate, install height, free height and end types on coil springs between the 95-96 and '97.

Just want to make sure I purchase the right stuff though I wouldn't be using a factory spring anyways. I should probably just go with the '97 struts and '95-'96 mounts but that's what I came up with in cross reference.

Weird, when I was looking I was seeing that 95-97 all had the same springs.

sall wrote:

I did a quick cross reference on rockauto and it seems the 95-96 use the same spring but the 97 is different.

Coil Springs:
95-96 Aurora/Riv - ACDELCO Part # 45H0354
97 Riv                 - ACDELCO Part # 45H2107
97 Aurora            - ACDELCO Part # 45H0286

Struts:
95-96 Aurora/Riv  - ACDELCO Part # 503353
97 Aurora/Riv       - ACDELCO Part # 503382

Moog specs show a difference in spring rate, load rate, install height, free height and end types on coil springs between the 95-96 and '97.

Just want to make sure I purchase the right stuff though I wouldn't be using a factory spring anyways. I should probably just go with the '97 struts and '95-'96 mounts but that's what I came up with in cross reference.

been years since i did mine, but if i recall the 95/96 top mounts will not work with 97+ struts because of the way they are setup with the center hole and rubber. You will have the strut rod hitting the hood.

Mr.Riviera wrote:

been years since i did mine, but if i recall the 95/96 top mounts will not work with 97+ struts because of the way they are setup with the center hole and rubber. You will have the strut rod hitting the hood.

It depends on what struts you get. If you run OEM 97+s they will work just fine, but my Gabriels had to be shaved a bit because they stuck up farther than the OEM ones. I thought I said something about that somewhere......

I didn't think they changed the strut mounts until '98. The '95-'97 mount stud went up through the strut tower and '98+ used bolts that went down through the strut tower into the strut mount.

Monroe 902930 Strut Mount Kit cross references to:

BUICK PARK AVENUE 1997
BUICK RIVIERA (1995 - 1997)
OLDSMOBILE AURORA (1995 - 1997)

Not trying to cause mass confusion here haha. I'm planning to run 06+ Lucerne(and others) calipers and 12"+ rotors that were for factory 17" wheels. I'll just roll with this parts list comparison break down.



I'll use 97-99 knuckles, 97-99 hubs, 97 struts, 95-97 strut mounts and brake upgrade and should be fine I think.

Sall, how did you manage to lower you 96 Aurora 1 inch? Did you have custom springs made? I have a 96 Riv and I'm about to install fresh stuts. If I'm gonna lower it, now would be the time. Thanks!

69GSColorado wrote:

Sall, how did you manage to lower you 96 Aurora 1 inch? Did you have custom springs made? I have a 96 Riv and I'm about to install fresh stuts. If I'm gonna lower it, now would be the time. Thanks!

A bunch of math and tracking down the proper coil springs. I don't know what the Riviera ride height from ground to center of wheel well is front and rear. So what worked on the Aurora may not work for the Riviera.

What springs did you use? Since the factory springs between the two cars are the same part number I'd be willing to try.