I just installed doug's IRS brace, and i must say, things went smoothly. here's a write-up on how to do it with pictures. there is also another good write-up with good pictures through zone 5 performance products (i don't have the link right now). doug's instructions are more than adequate, i just added a few more pictures.
you should NOT have to replace your differential fluid while doing this project. i had just a few drops seep out, but everything sealed up nicely when i reinstalled the bolts.
SUPPLIES NEEDED: 2 hydraulic jacks, jackstands, chock blocks, flathead standard screwdriver, torque wrench (20-100 ft/lbs), SOCKETS: 1/2", 11/16", 15mm, 18mm. RATCHETS: i used a 3/8" and then a 1/2" ratchet for a bit more torque to remove the front differential bolts. you will also need several different sized wobble extensions to try to get ratchets/torque wrenches into position. WRENCHES: 1/2" ratcheting helps to remove differential cover bolts, 18mm for the front differential mount bolts--i used a stubby wrench, but others have used a ratcheting wrench--i found that mine didn't fit, and finally, i used an 11/16" ratcheting to remove my passenger side exhaust.
BOLT/NUT SIZES: front differential mounting bolts-15mm, and the nuts are 18mm. rear differential mounting bolts-15mm, and the new bolts are 18mm. differential cover bolts-1/2".
TORQUE SPECS: front differential mounting bolts-52 ft/lbs. rear differential mounting bolts-76 ft/lbs. differential cover bolts-24 ft/bls.
here's a picture of the supplies i used, you can see the old bolts in the lower left of the picture that are replaced with longer bolts.
STEP 1: getting the car in the air. be very careful with this step. i always use both hydraulic jacks as well as jackstands. don't trust one or the other, use both. i've seen the results of cars falling on people and it never ends good. below is a pic of my car in the air. i always put down chock blocks on both sides of BOTH front tires before i do anything. next i place both my hydraulic jacks under the rear of the car coming at it from either side. the jacking point i use is a flat piece of steel that you can see one of the hydraulic jacks engaging in the picture below. i then alternate jacking up each side evenly about 5-6 pumps per side--you don't want to go crazy jacking one side up all the way and then going to the other side or else your car will 'walk' side to side.
once the car is up in the air high enough to fit the jack stands underneath it please do so--see the pic below for the jack stand placement. i then release each hydraulic jack making sure the jackstand is stable. i then use the hydraulic jack to just barely engage the underside of the jacking point--this is a safe catch, in case the jackstand fails. since i will be using the other hydraulic jack to raise the differential, on the other side i use 2 jackstands to ensure safety. now the car is up in the air safely. if you're wondering why i spent so much time on this step, it is because if you do this step wrong, you will be dead.
STEP 2: below is a picture of the IRS brace from billet flow, you can see i numbered the bolt holes 1-7. you will be able to locate the corresponding bolts on the differential on your car.
remove your passenger side exhaust. my car is equipped with a MAC system and it required removing 2 11/16" nuts, two rubber exhaust hangers, and a 1/2" nut on the tail pipe bracket. this will allow room to work, i'm almost certain it is necessary to remove your passenger exhaust to install the brace
STEP 3: remove the front differential mount bolts/nuts. this will allow you to raise your differential to install the bolt in hole #3, which is blocked by a black metal bracket. the bolt uses a 15mm socket (i used a 1/2" drive, for a bit more torque), and this is where you use your 18mm stubby wrench for the nut. i didn't have to do anything with the wrench--i placed it on top of the nut, and then used the ratchet to loosen the bolt. the wrench will spin until it buts up against the frame and then it will stay in place and the bolt will loosen. you can use this same principle when tightening the bolt. below are a few pics that show you where this bolt is located. in the first pic, you can see the socket extension with a 15mm socket on the bolt. in the sencond pic, you can see the socket, as well as the stubby wrench on the bolt above.
STEP 4: next remove the differential rear mount bolts-they are 15mm bolts. they are the bolts corresponding to holes #6 and #7 on the IRS brace. it is NOT necessary to have a jack under the differential at this time, as the differential is still held in place by the front mount bushings. anyways, after you remove these two bolts, you will be able to tilt the differential up a bit to install bolt #3 in a few minutes. below is a picture of the differential with most of the bolts numbered
STEP 5: at this time remove bolts 1-5-they are 1/2" bolts. to remove bolt #3, you will have to tilt the differential up just a bit. you can see #3 bolt is being blocked by the black bracket with the arrow pointing to it. notice i said 'tilt'. you will not be able to lift the differential, you will only be able to tilt the rear of the differential up and only a little bit. the differential is still held in place vertically by the front mount bushings, and they will be the fulcrum that you tilt the differential on. use your hydraulic jack to do this, and be careful not to put pressure on the differential cover itself.
STEP 6: once all the numbered bolts are removed, you can now fit the brace into position. at this time (with the differential still tilted up) you will only be able to install bolts 1-5--again 1/2" bolts. finger tighten them. at this time you will torque bolt #3 AND ONLY bolt #3 to 24 ft/lbs. i had to use multiple wobble extensions to get my torque wrench into position. billetflow also gives instructions on how to tap the bolt hole if any of your bolts bottom out before physically tightening the brace down (none of my bolts needed to be tapped)
STEP 7: now you can lower the differential down and install bolts #6 and #7--these are now 18mm bolts. to install #7, you may have to angle the bolt a bit to clear the black bracket that has the blue arrow pointing to it in the above picture. you may also have to play with the jack, raising and lowering the rear of the differential to start threading those two bolts, as they can be a pain to get started. do not torque them at this time
STEP 8: torque bolts 1,2,4,5 down to 24 ft/lbs. i could not tighten 1 and 2 with my torque wrench so i did those 2 by feel. 4 and 5 were easy to torque down. next torque down the rear differential mount bolts (#6 and 7) to 76 ft/lbs., again, now they require an 18mm socket. now you can reinstall the front differential mount bolts and nuts using the 15mm socket and the 18mm stubby wrench. torque the bolts down to 52 ft/lbs. finally re-install the passenger side exhaust.
STEP 9: lower your car. again be very careful. first remove the jackstands. next, when lowering the car, lower each side a couple inches, then lower the other side, then switch back and forth until the car is on the ground. remove the front wheel chocks. here's what mine looks like installed, its a shame its not more visible. the whole project took me 2 hours, taking my time and taking pics-no rush.
you should NOT have to replace your differential fluid while doing this project. i had just a few drops seep out, but everything sealed up nicely when i reinstalled the bolts.
SUPPLIES NEEDED: 2 hydraulic jacks, jackstands, chock blocks, flathead standard screwdriver, torque wrench (20-100 ft/lbs), SOCKETS: 1/2", 11/16", 15mm, 18mm. RATCHETS: i used a 3/8" and then a 1/2" ratchet for a bit more torque to remove the front differential bolts. you will also need several different sized wobble extensions to try to get ratchets/torque wrenches into position. WRENCHES: 1/2" ratcheting helps to remove differential cover bolts, 18mm for the front differential mount bolts--i used a stubby wrench, but others have used a ratcheting wrench--i found that mine didn't fit, and finally, i used an 11/16" ratcheting to remove my passenger side exhaust.
BOLT/NUT SIZES: front differential mounting bolts-15mm, and the nuts are 18mm. rear differential mounting bolts-15mm, and the new bolts are 18mm. differential cover bolts-1/2".
TORQUE SPECS: front differential mounting bolts-52 ft/lbs. rear differential mounting bolts-76 ft/lbs. differential cover bolts-24 ft/bls.
here's a picture of the supplies i used, you can see the old bolts in the lower left of the picture that are replaced with longer bolts.
STEP 1: getting the car in the air. be very careful with this step. i always use both hydraulic jacks as well as jackstands. don't trust one or the other, use both. i've seen the results of cars falling on people and it never ends good. below is a pic of my car in the air. i always put down chock blocks on both sides of BOTH front tires before i do anything. next i place both my hydraulic jacks under the rear of the car coming at it from either side. the jacking point i use is a flat piece of steel that you can see one of the hydraulic jacks engaging in the picture below. i then alternate jacking up each side evenly about 5-6 pumps per side--you don't want to go crazy jacking one side up all the way and then going to the other side or else your car will 'walk' side to side.
once the car is up in the air high enough to fit the jack stands underneath it please do so--see the pic below for the jack stand placement. i then release each hydraulic jack making sure the jackstand is stable. i then use the hydraulic jack to just barely engage the underside of the jacking point--this is a safe catch, in case the jackstand fails. since i will be using the other hydraulic jack to raise the differential, on the other side i use 2 jackstands to ensure safety. now the car is up in the air safely. if you're wondering why i spent so much time on this step, it is because if you do this step wrong, you will be dead.
STEP 2: below is a picture of the IRS brace from billet flow, you can see i numbered the bolt holes 1-7. you will be able to locate the corresponding bolts on the differential on your car.
remove your passenger side exhaust. my car is equipped with a MAC system and it required removing 2 11/16" nuts, two rubber exhaust hangers, and a 1/2" nut on the tail pipe bracket. this will allow room to work, i'm almost certain it is necessary to remove your passenger exhaust to install the brace
STEP 3: remove the front differential mount bolts/nuts. this will allow you to raise your differential to install the bolt in hole #3, which is blocked by a black metal bracket. the bolt uses a 15mm socket (i used a 1/2" drive, for a bit more torque), and this is where you use your 18mm stubby wrench for the nut. i didn't have to do anything with the wrench--i placed it on top of the nut, and then used the ratchet to loosen the bolt. the wrench will spin until it buts up against the frame and then it will stay in place and the bolt will loosen. you can use this same principle when tightening the bolt. below are a few pics that show you where this bolt is located. in the first pic, you can see the socket extension with a 15mm socket on the bolt. in the sencond pic, you can see the socket, as well as the stubby wrench on the bolt above.
STEP 4: next remove the differential rear mount bolts-they are 15mm bolts. they are the bolts corresponding to holes #6 and #7 on the IRS brace. it is NOT necessary to have a jack under the differential at this time, as the differential is still held in place by the front mount bushings. anyways, after you remove these two bolts, you will be able to tilt the differential up a bit to install bolt #3 in a few minutes. below is a picture of the differential with most of the bolts numbered
STEP 5: at this time remove bolts 1-5-they are 1/2" bolts. to remove bolt #3, you will have to tilt the differential up just a bit. you can see #3 bolt is being blocked by the black bracket with the arrow pointing to it. notice i said 'tilt'. you will not be able to lift the differential, you will only be able to tilt the rear of the differential up and only a little bit. the differential is still held in place vertically by the front mount bushings, and they will be the fulcrum that you tilt the differential on. use your hydraulic jack to do this, and be careful not to put pressure on the differential cover itself.
STEP 6: once all the numbered bolts are removed, you can now fit the brace into position. at this time (with the differential still tilted up) you will only be able to install bolts 1-5--again 1/2" bolts. finger tighten them. at this time you will torque bolt #3 AND ONLY bolt #3 to 24 ft/lbs. i had to use multiple wobble extensions to get my torque wrench into position. billetflow also gives instructions on how to tap the bolt hole if any of your bolts bottom out before physically tightening the brace down (none of my bolts needed to be tapped)
STEP 7: now you can lower the differential down and install bolts #6 and #7--these are now 18mm bolts. to install #7, you may have to angle the bolt a bit to clear the black bracket that has the blue arrow pointing to it in the above picture. you may also have to play with the jack, raising and lowering the rear of the differential to start threading those two bolts, as they can be a pain to get started. do not torque them at this time
STEP 8: torque bolts 1,2,4,5 down to 24 ft/lbs. i could not tighten 1 and 2 with my torque wrench so i did those 2 by feel. 4 and 5 were easy to torque down. next torque down the rear differential mount bolts (#6 and 7) to 76 ft/lbs., again, now they require an 18mm socket. now you can reinstall the front differential mount bolts and nuts using the 15mm socket and the 18mm stubby wrench. torque the bolts down to 52 ft/lbs. finally re-install the passenger side exhaust.
STEP 9: lower your car. again be very careful. first remove the jackstands. next, when lowering the car, lower each side a couple inches, then lower the other side, then switch back and forth until the car is on the ground. remove the front wheel chocks. here's what mine looks like installed, its a shame its not more visible. the whole project took me 2 hours, taking my time and taking pics-no rush.
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