Rear Disk Brake conversion
Two sets of trailing arm bushes (recommended).
New brake pads (if required).
Fresh brake fluid.
Unless the trailing arms have nearly new bushes it is worth changing them before you start as they do deteriorate and are cheap and easy enough to replace at this point. I used a piece of pipe, threaded rod, nuts and washers to draw the old bushes out and new ones back in but an engineering firm can do this for you if you wish.
You may need to remove the filler pipe from the fuel tank to remove the driver’s side trailing arm so run the tank as low as possible before attempting this job.
This guide is written assuming that the replacement trailing arms are ready fitted with the drive shafts, discs, calipers, pads and handbrake cables/shoes.
1. Jack up the rear of the car and support on axle stands.
2. Spray all hydraulic brake line couplings, trailing arm mounting bolts and the handbrake cable where it joins with the body on top of the fuel tank with lots of WD40 and allow to soak in.
3. Remove wheels.
4. Slacken and remove the drive shaft to diff flange bolts (8mm Allen bit), using the handbrake to stop the driveshafts from turning.
5. Cable tie or tape the driveshafts to the trailing arms to keep them out of the way.
6. Disconnect the rear exhaust mountings and drop the exhaust to give access to the trailing arm mounting bolts.
7. From inside the car lift the handbrake boot and remove the handbrake cable adjusting nuts (10mm).
8. Using pliers or grips work the handbrake cables out from the metal conduit tubes that run over the top of the fuel tank, cable tie them to the trailing arm.
9. Slacken and remove the trailing arm mounting nuts (19mm).
10. Remove the anti-roll bar mountings from the trailing arm and swing out of the way (if fitted).
11. Carefully slacken and remove the flexible brake hose to metal brake line connection on each trailing arm (11 and 14mm spanner).
12. Remove the bottom mounting bolt from each shock absorber.
13. Lift out the spring from its locating points.
14. Support the trailing arm with a trolley jack and remove both mounting bolts, you may have to remove the filler pipe from the fuel tank on the drivers side as one bolt is quite close to the pipe.
15. Carefully remove the trailing arm from the car; Be aware that each arm weighs around 40 kilos so be prepared.
16. Place the new trailing arm into the mounting points and fit the mounting bolts, fit the nuts and torque to 62 Lbft, Refit the fuel filler pipe if you removed it.
17. Fit the spring into its locating points.
18. Raise the trailing arm with a jack and fit the bottom shock absorber mounting bolt and torque to 62 Lbft.
19. Connect the flexible brake hose to the metal brake line on the trailing arm not forgetting the metal spring clip.
20. Route the handbrake cables through the metal tubes above the fuel tank.
21. Refit the anti-roll bar links.
22. Inside the car fit the handbrake cable adjusting nuts and tighten so that when the handbrake lever is down the nuts just touch the metal stops.
23. Refit the driveshafts to the diff flange and torque to 60 Lbft.
24. Using fresh brake fluid, bleed the brakes.
25. Refit the exhaust mountings.
26. Adjust the handbrake so that the discs turn freely when the brake is off but is fully on @ about 5 clicks on the handbrake lever.
27. Refit the wheels and remove the axle stands.
28. Pump the brakes with the engine running.
29. Carefully test-drive the car.