Bob and Rob's Gen 2 Aluminum Rear Knuckle and Brake Upgrade. How-To with Pics

[BXX]

Gen 2 Aluminum Rear Knuckle and Brake Upgrade

This is the definative and step-by-step how-to on how to upgrade your Gen 1/1.5 W-body. Rob (Venom) and I made sure to get good pics last night so you know what your looking at. Meaning even a Noob should have ZERO issue doing this.

There is a bit of a prerequisite however, if you have a Gen 1, you must have rear coilovers! Gen 1.5 already has these so there is no issue with the missing leaf spring perch on the knuckles.

For the non-believers, there is indeed a difference. For starters, you drop around 10lbs per side (Havent weighed them yet) , you get rear brakes with a better caliper that isnt known to seize up (mainly the slides) like the 88-93 and 94+ setup, and later down the road, if you wanted to upgrade to larger rear brakes, there are known aftermarket options out there.

Also, it is not known if the ABS will function just the same. It appears you can swap your original hubs over to the new knuckles but I have not verified this yet. Also, it appears the Gen 2 hub's ABS connector is the same. Again, I have not verified this. Our cars stock ABS system sucks, period! IMHO is damn near useless and even when working 100%, it rarely works correctly to keep the wheels from locking up and helping you stop earlier. If you have driven newer GMs and even imports around the same age as our cars, you'll agree that our ABS system is inferior.

So lets get started!! Lets start with the parts list!

Parts from a 97-03 GP/Regal is your best bet to snag from at the yard.

-Rear knuckles (nice and light aluminum!)
-Rear hubs (Stock appears to swap over ok, but havent verified yet)
-Rear caliper brackets
-Rear cailper bracket bolts
-Rear calipers
-Rear caliper banjo bolts
-Rear caliper pins
-Rear rotors
-Rear pads
-Strut to knuckle bolts (You CANNOT reuse your orignal ones!)
-Knuckle to lateral arm bolts, washers, nuts

You will reuse these items!

-Trailing arm bolts and nuts
-Brake hoses
-Brake hose to body brackets

Other items you will need/recommended!

-2 self tapping screws
-Brake fluid Dot3/4 (Incase a Noob doesnt know)
-Brake line (3/16")
-Metric bubble flare fittings (if your old ones are too bad to reuse)
-Brake parts cleaner
-Someone to help you bleed the brakes

Alright, now for some W-body moddin madness!!

Step 1- Jack up vehicle, securely on jackstands
Step 2- Remove the wheels, 19mm


Step 3- Unbolt caliper bracket from knuckle, 18mm



Step 4- Using small prybar, pry caliper and bracket as an assembly, off the rotor. Hang outta the way




Step 5- Remove rotor. If stuck, hit with hammer on the front, a few good swings will knock it right off.


Step 6- Remove trailing arm from knuckle. 24mm socket and 24mm wrench. If siezed, hammer outta the knuckle


Step 7- Remove lateral link to knuckle bolts, 21mm



Step 8- Remove strut to knuckle bolts, 22mm. Hammer out of knuckle




Step 9- Now remove the ABS harness fromt the back of the hub if equipped and remove the knuckle assembly from the vehicle and take it out back and piss on it!!!



Step 10- If not going through the hassle to get the Gen 2 rear e-brake to work, might as well remove it and save you a headache later in life when the shoes wear into the rotor or just rot away and make noise. Remove the hub, 10mm


Step 11- Hammer the shoes down outta the way, and hammer the flange of the hub to remove it from the knuckle



Step 12- Scrap corrosion from the knuckle where the hub fits


Step 13- Cut backing plate like so, you need this is as a spacer to keep everything lined up.





Step 14- Slide on cut backing plate and reinstall hub into knuckle. NOTE! 1 hub to knuckle bolt needs to be a short one from the stock Gen 1 knuckles, otherwise it will hit the lateral arm. The short ones need installed in the bottom front side



Step 15- Mount knuckle onto car, start with strut to knuckle bolts. Use smaller Gen 2 bolts and nuts! 21mm or 22mm

[BXX]

Step 16- Mount lateral arms to knuckle using new long through bolt with washers and nut. 21mm




Step 17- Mount trailing arm using the stock bolt and nut 24mm socket and 24mm wrench




Step 18- Laugh at Ryanna!!


Step 19- Cut corner from body. Makes for more room for brake hose to come out and not get damaged. Smooth out burrs





Step 20- Slide on new rotor


Step 21- Bolt up new caliper bracket. 14mm or 15mm. Install new hardware clips (can reuse original) and install new pads


Step 22- Install caliper. IIRC the guide pins with the rubber bushing go to the bottor. 14mm or 15mm


Step 23- Remove stock caliper from brake hose. Banjo bolt is normally 11mm. Can vary


Step 24- Remove brake hose bracket to body. 10mm


Step 25- Remove clip holding hose to bracket


Step 26- Remove brake hose from hard line, vise grips with 16mm wrench will work


Step 27- Hammer bracket off hose


Step 28- Attach hose to bracket and caliper, find a good spot to mount the bracket and mount it using the self tapping screws. It may take some removing and installing of the hose to get everything in a good spot and not twisted to hell. You will have to tweak the original brake line around. It will fit good with no issues.






-Passenger side mounting of brake hose bracket with line. Had to run new line to passenger. Driver side was mint.


Step 29- Make sure everything is good and tight, and that the hoses are not kinked. Rob used Goodridge lines on his, I used stock lines on mine. Neither had any rear fitment issues.

Step 30- Bleed brake system. Our system is split-diagonal so your best bet to bleed the system is to go in this order. RR-LF-RF-RR. Then do the pattern again and everything should be good to go.

Step 31- Sit back and enjoy the fruits of your labor!!!




And a few random pics.

-Comparison of the stock Gen 1 and Gen 2 knuckles


-Teh Flows Yo!!! (aka Flowmasters)


-Gen 2 parking brake show and adjuster. If you want to keep these and get a working cable setup, take into account new shoes are over $50, so get a nice set at the junkyard!


-Whole mess of parts ready to go on.


-Robs ass crack!!


-Rob takin pictures of my junk!! I have no clue what was happening here.. I plead the 5th, I already had a few beers in me!


Enjoy!! Feel free to ask questions as well.

-Bob

[tornado_735]

Awesome writeup! Even a tard like me can understand it!

[94GPGTP]

size of the rear sway bar? Which vehicle it came off of... Or is it a addco?

[jeremy]

very nice write up but you should really add a step to include cleaning/painting the old rusty caliper before reinstalling

[BXX]

size of the rear sway bar? Which vehicle it came off of... Or is it a addco?

7/8" (22mm)

95 LQ1 equipped MC/Lumina. Possibly 96 as well. Be careful as not all of those even got the larger 22mm bar.

[BXX]

very nice write up but you should really add a step to include cleaning/painting the old rusty caliper before reinstalling

I made a comment about it to him, but between I think him forgetting and also could care less since the exterior needs some rust repair and body work.

[jman093]

Awesome! I was going to do this myself, this makes it a whole lot easier. Couple of things. First, the parking brake. Some cars got a caliper with an integral parking brake. The Regal/GP you guys got obviously doesn't have it and my neiter my father's 01 Monte SS or my Mom's 06 Impy has it either, but I just today saw in the shop today a 3G GPGT with this integral style parking brake on the back of the caliper. It LOOKED just like the one on our calipers from the spring on the back to the way the cable attaches. Don't know for sure if it's the same without having each one available to compare next to each other, but I'm sure it could be made to work. I'm going to look into this.

EDIT: I was just looking up parking brake descriptions in service information for a bunch of different 2nd/3rd gen W-bodies and the 3G GP got this style caliper and is the only W-body to get a retractable integral parking brake since gen 1/1.5's. All other 2/3's have the drum setup for parking brakes. Not sure why GM would do this.

Second, what about all the different sizes on the rear brake packages? Obviously the GXP has larger brakes, but it is different setup. I want to to say the 00+ Impy/Monte had larger brakes on some or all of the cars, but I don't know for sure. Would be nice to get the biggest brakes possible.

[White93z34]

excellent information! I think this will become a write up shortly!

[BXX]

04+ GPs are the only ones to get integral parking brake. Again, those calipers have more siezing issues. K.I.S.S.

AFAIK, the Impy and MC could get larger front ones or just slightly different. As far as the rear is concerned I dont believe they got anything different. Ill have to look into it more. But if you want bigger brakes, then the 12" GXP setup is the way to go. Our cars need larger front brakes way before 12" rears. The 97-03 rear setup works great.

If you wanna keep the parking brake, which works great, and if you have cable issues, almost any area has a place that can make custom cables for a very reasonable price. Just swapping over cables and the pedal assy from a 97-03 GP prolly wouldnt be too hard. I may actually look into that on my next run to pullapart.

[jman093]

I've been doing more digging. Here's what I found out about rear brakes on W-bodies. All 94+ w-bodies (1G,2G,3G) rear rotors are 278mm(10.94") except the following:

3G GP's which have a 270MM (10.63") rotor
GP GXP's have the 12" rear brakes. There's 2G GP's running these on stock wheels, so I think they would fit our 16" wheels as well. We'd probably have to find a larger spare tire though from a yard.

The other factor into performance though is the brake pad size differences, if there are any since the surface area of the pads would also affect performance. I'm guessing the 3G rotors are only smaller due to the lack of the brake drum in them and they may actually have more pad surface area. Would be interesting to see the different pad sizes.

I think I am going to try the 3G GP brakes when I get around to doing mine. Personally I haven't seen any siezing issues on 3G GP's. It's a way better caliper than even the 94+ ones. The other advantage is it's aluminum for even more unsprung weight savings than is provided with the knuckle swap and lack of a parking brake shoes. All other w-body rear calipers are the iron/steel except the PBR's on the GXP's, but even those paired to a heavy ass 12" rotor.

[Skunkworks_Zed]

I've been doing more digging. Here's what I found out about rear brakes on W-bodies. All 94+ w-bodies (1G,2G,3G) rear rotors are 278mm(10.94") except the following:

3G GP's which have a 270MM (10.63") rotor
GP GXP's have the 12" rear brakes. There's 2G GP's running these on stock wheels, so I think they would fit our 16" wheels as well. We'd probably have to find a larger spare tire though from a yard.

The other factor into performance though is the brake pad size differences, if there are any since the surface area of the pads would also affect performance. I'm guessing the 3G rotors are only smaller due to the lack of the brake drum in them and they may actually have more pad surface area. Would be interesting to see the different pad sizes.

I think I am going to try the 3G GP brakes when I get around to doing mine. Personally I haven't seen any siezing issues on 3G GP's. It's a way better caliper than even the 94+ ones. The other advantage is it's aluminum for even more unsprung weight savings than is provided with the knuckle swap and lack of a parking brake shoes. All other w-body rear calipers are the iron/steel except the PBR's on the GXP's, but even those paired to a heavy ass 12" rotor.

Diameter isn't everything The stock '97 rotors that I used were definitely thicker than the '93 and '94 ones that I had around. Also, while OEM cast aluminum calipers do save weight, they flex far too much for any other benefit. I would rather shave some weight off of the iron calipers/brackets, and save up for a good 2-piece aluminum caliper.

Edit: '94+ spare tires will fit, '88-'93 is too small.

And Bob; I did this swap almost 3 years ago, and I haven't had any ABS issues. I used '97 hubs, since my stock '93s had broken connectors. They will mount just fine though, so using some Gen1 non-ABS hubs would work.

[Venom]

Awesome writeup bro! I think you pretty much covered it all. This project went very quick even with us taking our time to document and take pics, smoke/pizza breaks and me drinking a whole 12 pack almost by myself LOL. It is definitely a nice upgrade from my stock brakes since the RR was constantly seized and the aluminum knuckles shave some weight as well.

And Jeremy, the calipers will be painted shortly, I just wanted to get the swap done first without messing up any paint job, plus I need new pads since the ones I got from the donor vehicle were worn more then I remembered.

[GOT2B GM]

Nice write up, the only thing I don't like is the bent up brake lines.

[BXX]

What do you mean? The brake line is perfectly fine. Last time I checked the OE line had bends in it too!

And Rob, you only drank 5 beers scooter...