How-To: Supra Subframe Swap
Toyota Differential Codes
This swap will only work on a 1982-85 Celica that already has independent suspension. This swap will give your Celica an F series (7.5") differential and rear disc brakes. You should locate and remove the assembly from the donor car before beginning work on your car. Be sure to check the differential for signs of obvious ware and listen for any odd sounds. Now would be a good time for new (polyurethane) bushings, brake lines, CV boots and a brake system flush. You will almost certainly have to replace the rotors and it would be a good idea to replace or rebuild the calipers. You should also replace the differential side seals; they will leak soon if you don't.
If you want your speedometer to read accurately you will need to swap the speedometer gears. You may need just the driven gear, or you may need both the drive and driven gear. There are two numbers on the front of the driven gear. Lets say 10 and 31. 10 is how many teeth the drive gear has 31 is how many teeth this driven gear has. Compare these numbers to the driven gear from your transmission. If the smaller numbers are the same then just swap the driven gear in. But if the smaller numbers are different then you have to swap both the drive and driven gear.
To swap the drive gear on a manual you will have to remove the tail shaft from the transmission and pull the original drive gear off, then slide the new one on. This may be the same for automatics but I cannot say for sure as I haven't done this to an automatic.
- Rear Suspension Assembly from 1982-86 Toyota Supra
- Complete Metric Socket Set & Ratchet (1/2" drive)
- Metric Open End Wrench Set
- Breaker Bar (1/2" drive)
- A strong friend or two to help you get it out of the junk yard 
- Remove the rear wheels
- Disconnect the parking brake cable from the handle (2 nuts) 
- Pull the parking brake cable from the chassis clips 
- Disconnect the driveshaft at the center carrier bearing 
- Disconnect the rubber brake lines from the metal lines on the chassis
- Disconnect the shock absorbers from the suspension arms
- Release the fuel pump from the bracket on the differential carrier crossmember (If applicable) 
- Disconnect the support plates from the chassis. 
- Double check to make sure nothing is in the way. All pieces should be hanging free (driveshaft, parking brake cable, brake lines, fuel pump & lines)
- Remove the nuts that retain the rear crossmember and the differential carrier crossmember (4 total) 
- Remove the brake proportioning valve 
- Installation is reverse of removal
- Be sure to bleed the brakes very well
- Check differential and brake fluid levels
- Make sure the brake peddle has resistance an is functioning properly
- After a short low speed drive check all bolts/nuts
- Recheck all bolts/nuts after 10 miles, then 50 miles, then 100 miles. If the ever go slack, repeat
- The whole assembly weighs almost 300lbs. You WILL need help.
- Be sure to pull the cable free under the chassis so it doesn’t get caught up when you drop the rear end.
- You will need the parking brake cable for the disc brakes.
- The clips are located in the sides of the driveshaft tunnel. About a foot back from the center bearing.
- You will need the back half of the driveshaft.
- Make sure the fuel pump will not get caught on anything when you drop the rear end.
- The support plates are pieces of metal that go from the main crossmember nuts to the chassis. Only remove the smaller bolts that hold them to the chassis, not the main crossmember nuts
- I would suggest starting with the right nut on the differential carrier because you will have your arm pined between the gas tank and rear end. Then move to the left bolt on the main crossmember, then the left bolt on the differential carrier crossmember, then the final bolt on the main crossmember.
- Be VERY careful when you remove the final bolt. When the rear end drop with will go down with a big force and can easily break an arm. The rear end may not fall once the last bolt is removed. If it sticks DO NOT go under the car. Instead push down on the brakes until it drops. If it will not drop reinstall the 4 big nuts and then check for other connections.
- The brake proportioning valve can be found behind the intake plenum of Celica's or on the driver side strut tower on Supra's.
- You will a brake proportioning valve that matches the one you already have. Most Celica's use a 4-line valve while most Supra's use a 5-line valve. You can use the valve from any Celica with four-wheel disc brakes if it matches. You must have this piece or your new brakes will not function correctly.
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