Rear Disc Conversion for any BJ model (99-03), NO FABRICATION METHOD

1999 Mazda Protege ES
Hello everyone! First of all, this is my first post to the forums and I plan to frequent these parts in the future.

As far as I could tell, my search on this forum has shown me that the only methods posted require fabrication/welding of mounts. I have manages to find a way that only requires the swapping of parts! Areas marked in bold are important details.

This method requires you to convert to 5 lug so bear in mind that you'll need new wheels.
Be advised that this conversion may take more than one day of work depending on skill level so be prepared to have your car disabled for a couple days or make arrangements.
This conversion is semi-permanent. If you ever have to part ways with your car, make sure you let the next owner know what parts to get.

This conversion works for:

  • 99-00, all models, auto or manual
  • 01-03, DX or LX, auto or manual

So without further ado, these are the parts you'll need:


  • 01-03 ES Sedan hubs (5 lug)
  • New hub bearings and wheels seals (you'll destroy the old ones trying to press the hub off)
  • 01-03 ES or P5 rotors (5 lug)


  • Knuckle/hub/backing plate combo from a donor car. Mine came from an 03 ES sedan at the wreckers. Not sure if P5 ones work. If you have ABS, make sure your donor parts have the holes to mount the sensor! Rear hubs are a pain in the beach to find so take them!
  • 01-03 ES or P5 pads, rotors, and calipers. I lucked out and found a wrecked P5 with like-new calipers (parts store wants $90 + core EACH!!!)
  • 01-03 ES rearward lateral link (lateral arm). This is important because for some reason the size of the bushing is different. The original ones sort of fit but they can f*** up your alignment. If you don't want wrecker parts, Megan Racing makes adjustable length ones that will fit.
  • 01-03 ES or P5 parking brake cable, unless you like to live on the edge with no parking brake. Side note: you'll need the spring clips that go on the calipers that hold the parking brake in place. New/reman ones will not come with them.
  • New lateral link bolt. P/N: 9YA1-11-204. This is the bolt that goes all the way through the knuckle and lateral links. I got mine $20 each from my dealer. You can find them online for cheaper but by the time you add shipping it's better to buy genuine. Read below to find out why you need these.
  • 01-03 ES or P5 rear brake hoses.
  • 01-03 ES or P5 banjo bolt for the caliper.


  • Extra lug nuts. All mazdas of this era used the same lug nuts so grab a few from the wreckers.
  • Your choice of wheels.
    - Stud pattern is 114.3x5.
    - Any size 14-17" will work, but I recommend 15 or 16.
    - Any width 6-7.5" will work, however 7.5 will require rolling the fenders
    - Any offset around +45mm should work. Higher number = further inward, Lower number = further outward.
  • If you've run out of money by this point, you can go find a first gen MPV with steelies and they are direct fit. Wrecking yard only charges like $10 per wheel. Bonus: if you had 195 size tires, they'll mount on too, so no need for new tires.

(Sorry in advance for no pictures. My phone was SOL through most of the process.)
  1. Front. Loosen axle nut with wheels on ground. Cheater pipe may be needed.
  2. Remove wheels and all brake parts. If you have ABS, remove those sensors too.
  3. Unbolt struts and tie rods.
    - Pickle fork is not recommended; you will likely damage the tie rod end.
    - Find a spare nut, put it on loose and hammer upward on the nut while you/a friend pries up on the tie rod. Be careful not to damage the threads.
  4. Remove front axle.
    - If they don't come out easy, rent a FWD axle puller from a parts store. Usually $30 and well worth it to save effort.
  5. Unbolt/disconnect knuckle from lower ball joint.
    - Pickle fork is not recommended; you will likely damage the ball joint.
    - Pry open the pinch bolt, use brass hammer and use PB Blaster or equivalent to remove.
  6. Take the knuckles to a machine shop and have them use their press for the hub and bearings. My local place charged me $50 each for labor. If you have access to a press, more power to you.
  7. Installation is literally the reverse of the install process. The only exception is obviously using the new rotor. I'd recommend new pads at this point too. Avoid organic material. They're terrible for anything more than driving to the shops and back. Make sure to torque all bolts to spec. The last thing you want is to lose control down the road.
  8. When you're finished, it should look something like this
  9. Rear. Remove wheels.
  10. Remove drum. If you have trouble removing the screws, use an impact driver. Harbor Freight sells them for cheap. Use a hammer to tap/bang the drum off. you won't be needing them anymore! (sssh)
  11. Taking apart the brakes isn't necessary but it can be easier to work without all the stuff in the way. Just be careful not to catch your fingers on the springs.
  12. Disconnect the wheel cylinder from the brake line with a line wrench.
    - Use hose pinch pliers on the rubber part of the hose to avoid emptying your brake system especially if you have ABS.
    - Make sure you have a drip pan cause brake fluid is nasty stuff.
  13. Loosen but do not remove all the hardware that bolts to the knuckle. This is where things can get rough...
  14. The long lateral link bolt can be a tough bugger. 99.999999% of the time they are rust-welded to the knuckle. This is where you'll need those new bolts.
    - Remove the nut and washer.
    - Soak the entire bolt in PB blaster or equivalent. You'll need something more penetrating than WD-40 for this one.
    - Optional: use a torch on the bolt. It helped on one side but not the other for me.
    - Take your heaviest sledge and hammer the s*** out of the bolt. If it mushrooms a little bit, that's okay. File it down if it gets excessive.
    - Get the bolt part way force through. Take a saw with metal blade and cut the bolt between the knuckle and the rear lateral arm.
  15. Remove trailing arm bolt, then strut bolts. The knuckle should now be free.
  16. Cut the old parking brake off. You won't need it anymore.
  17. Remove/replace the rear lateral link.
  18. Install the donor knuckle. A couple notes:
    - Don't forget to put the washers back on. Those are there so that if one of the bushings fail, the lateral link doesn't fall off completely. Safety first!
    - Put some anti-seize on the shaft of the long bolt so it won't get stuck again.
    - Put some blue Loctite on the threads. The car came with some on there so don't risk going without it.
    - I torqued all bolts to 80 ft-lbs cause I couldn't find a spec anywhere.
  19. Remove the retaining clips that hold the old brake line onto the car.
    - Notice that on the new and old lines, where they clip on, there is a unique shaped flange. These will only fit in one way, so don't force it if it's not fitting right
  20. Remove the old brake line at the connection on the inner fender.
    - If you have another one, use hose pinch pliers to pinch the new hose before you install.
    - Try to be quick installing the new hose so you don't lose much fluid.
  21. Install the new line, paying attention to the orientation of that flange I mentioned earlier. It should still route the same through the mounts.
  22. Install the retaining clips onto the new line.
  23. Install new brake parts and connect brake line to caliper.
    - Use new copper washers on the banjo bolt. This WILL leak if you don't use any.
    - Be careful not to over-tighten this because it will ruin your new caliper.
    [*]Bleed the brakes and seat the pads.
    [*]Parking brake. Loosen the adjustment nut on the handle in the car, just in case.
    [*]Undo the bracket on the trailing arm.
    [*]Undo the bolt under the car where the cable bends.
    [*]Unbolt the heat shield above the exhaust. Once loose, you should be able to slide it forward out of the way.
    [*]Unhook the old cable from the splitter. Note that the cable cross to the opposite side.
    [*]Install new cables reversing the removal procedure.
    [*]Hook the cable through the bracket, then onto the caliper itself.
    [*]Install heat shield back in place.
    [*]Put the car on the steepest incline you can find. Put it in neutral and tighten down the adjustment nut until the parking brake holds the car with 5-8 clicks.
    [*]You're finished! When you're done, it should look like this!

This conversion also opens up new possibilities for even more upgrade! Now that you're 5 lug like every other Mazda (except the Miata crowd) you can swap in parts as you'd like! Common mods seem to be Mazda6 front brake conversions.

Please let me know if you need additional info!
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Mazda, Protege ES, sedan 1.8L 5-speed
This is so great to have someone care enough to get this thorough. On behalf of us all, THANK YOU!!!!!