Rear subframe removal
#1
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1) When removing the rear subframe (with everything connected as one unit), should I unbolt the PPF from the tranny or from the diff? Which one will make life easier?
2) If I remove PPF from diff, won't it be like a cantilever and jack up my tranny?
3) Is there any way to avoid draining the brake fluid when disconnecting from the brake block? I hate bleeding brakes.
2) If I remove PPF from diff, won't it be like a cantilever and jack up my tranny?
3) Is there any way to avoid draining the brake fluid when disconnecting from the brake block? I hate bleeding brakes.
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1. I'm guessing the transmission would be easier, as you wouldn't have to deal with the diff's PPF spacers. However depending on what you need to do with it off the car, it would probably be easier to do it on the car. Thread the unshouldered long bolt into each hole a few threads and hit it with a hammer to remove the top splined nuts, and then remove the spacer thats at the top. It'll make your life very easy.
2. The transmission will actually fall down, pivoting on the motor mounts.
3. No.
2. The transmission will actually fall down, pivoting on the motor mounts.
3. No.
#3
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Remove the PPF from the transmission and then pull the rear subframe and diff. Removing the PPF from the diff under the car is a royal pain in the ***, hell I hate having to do it when it is off the car on the ground and you have full access.
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I did this on a old 90 that I had to swap the gastank on.
Remove PPf entirely, it is just so much easier to get it out of the way. Open the shifter and support the back of the tranny with a strap trouh the shifter hole. If you support the tranny like this you can keep the PPF attached to the tranny, but it will still get in the way of the diff and other parts.
Here is a good trick for the brake fluid. Stick a jack handle or something in between the seat and brake pedal. Make sure it remains depressed when the brake line is cracked. This moves the master piston to a position where it is not takeing fluid from the reservoir and keeps you from gravity draining from the reservoir. You will still have to bleed it since you cracked a line, but you won't be dry all the way from the reservoir to the caliper. I had a master mechanic show me that trick when I did the subrame removal on the 90, he was also nice enough to let me use on of the lift bays at his work.
Remove PPf entirely, it is just so much easier to get it out of the way. Open the shifter and support the back of the tranny with a strap trouh the shifter hole. If you support the tranny like this you can keep the PPF attached to the tranny, but it will still get in the way of the diff and other parts.
Here is a good trick for the brake fluid. Stick a jack handle or something in between the seat and brake pedal. Make sure it remains depressed when the brake line is cracked. This moves the master piston to a position where it is not takeing fluid from the reservoir and keeps you from gravity draining from the reservoir. You will still have to bleed it since you cracked a line, but you won't be dry all the way from the reservoir to the caliper. I had a master mechanic show me that trick when I did the subrame removal on the 90, he was also nice enough to let me use on of the lift bays at his work.
#9
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I did this on a old 90 that I had to swap the gastank on.
Remove PPf entirely, it is just so much easier to get it out of the way. Open the shifter and support the back of the tranny with a strap trouh the shifter hole. If you support the tranny like this you can keep the PPF attached to the tranny, but it will still get in the way of the diff and other parts.
Here is a good trick for the brake fluid. Stick a jack handle or something in between the seat and brake pedal. Make sure it remains depressed when the brake line is cracked. This moves the master piston to a position where it is not takeing fluid from the reservoir and keeps you from gravity draining from the reservoir. You will still have to bleed it since you cracked a line, but you won't be dry all the way from the reservoir to the caliper. I had a master mechanic show me that trick when I did the subrame removal on the 90, he was also nice enough to let me use on of the lift bays at his work.
Remove PPf entirely, it is just so much easier to get it out of the way. Open the shifter and support the back of the tranny with a strap trouh the shifter hole. If you support the tranny like this you can keep the PPF attached to the tranny, but it will still get in the way of the diff and other parts.
Here is a good trick for the brake fluid. Stick a jack handle or something in between the seat and brake pedal. Make sure it remains depressed when the brake line is cracked. This moves the master piston to a position where it is not takeing fluid from the reservoir and keeps you from gravity draining from the reservoir. You will still have to bleed it since you cracked a line, but you won't be dry all the way from the reservoir to the caliper. I had a master mechanic show me that trick when I did the subrame removal on the 90, he was also nice enough to let me use on of the lift bays at his work.
#11
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I literally just did all of this on Saturday. Remove the whole PPF. You've got a '91, so it's EASY to get it off of the diff, as the collar in yours is threaded. You need a big *** M14 bolt. It will run you a few dollars at the hardware store. Get it pretty long.
After you take out the front bolt on the diff, you will need to pry out the spacer. It shouldn't be hard, it's not splined. Then thread the M14 bolt into the collar in the nose of the diff, and use it to pull the collar down out of the PPF. The PPF should come off of the nose of the diff easy after that. It's a little difficult to get back on, but not bad.
Make sure you get all of the clips holding the battery cable! There's one high up on the subframe itself that I missed.
After you take out the front bolt on the diff, you will need to pry out the spacer. It shouldn't be hard, it's not splined. Then thread the M14 bolt into the collar in the nose of the diff, and use it to pull the collar down out of the PPF. The PPF should come off of the nose of the diff easy after that. It's a little difficult to get back on, but not bad.
Make sure you get all of the clips holding the battery cable! There's one high up on the subframe itself that I missed.
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