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Rear Subframe Mount Renewal Concerns


GoldLion
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Hi guys, just going about renewing the rear subframe mounts. From the searches, it would seem that these can be done fairly straightforwardly by getting the rear onto jack-stands, then performing the exchange one side at a time by lowering the respective subframe side on a jack.

Ok I have the rear supported on stands with timber placed longitudinally along the rocker seams. I have removed the subframe-chassis strap and removed the nuts from the bushing-to-subframe bolts. Supporting the subframe on the side I am working on, I have gently lowered the jack. The problem is that the bushing is catching on the knurled vertical stud (which passes through its centre) about half way along and does not seem to want to move further. What I want to know is:

1 - DO I need to loosen any other mountings for the rear subframe/diff at all (the opposite side is still bolted on tight - I am wondering if I should loosen that side as well, or the diff mounts or whatever)?

2 - DO I need to disconnect the C-V joint from the rear hub and also the rear shock to allow extra movement?

OR

3 - should I just force it AND IF I DO:

4 - will the poo hit the fan when that bushing finally clears the knurled stud, with dramatic relocation of the subframe ?

Many thanks for your contributions in advance. Keep on truckin',

Daniel.

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Actually, I went and got it for you.. If your car is lowered and has significant negative camber, while you're in there, flip them over and side to side. You can gain back a few degrees of camber for free... I totally forgot to when I did the following and I'm ticked about it!!

So, I was nervous here, as usual with uncharted territory. And once again I found myself rolling my eyes at how simple this process was.

Old vs. New:

Mine had to be original, dated 1974!

IMG_7628.jpg

Tools needed:

Jack

2 sets of jack stands if possible, but not 100% necessary

22mm socket

17mm socket

Heavy flat head screw driver

Hammer

1. Jack the car up to a comfortable working height and put jack stands under the rear subframe.

2. Lift it a bit more and move the stands to the rear jack points on the rockers, or use a second set here. If using a second set, move the fist set out of the way here (see picture)

IMG_7635.jpg

(don't judge me for the leaks. the diff is getting swapped and the tank was just drained and flushed..)

3. Remove mount through bolts with 22mm socket. Hammer up on the bolt to make removal possible.

4. Carefully lower the jack about 1-2 inches to let the subframe drop just enough to get a screw driver in to hold the bolt heads and to align the mount in the wheel well cut out (see pic).

IMG_7634.jpg

5. Remove the mounting bolts with the 17mm and the screwdriver to hold the heads.

6. Install new mounts in reverse process.

7. Remove rear seat to gain access to the large through bolts.

8. Get the bolts started into the new mounts. These guys are splined at the top and pressed into their holes. So with a light tough, twist them until you can feel the splines find their seat.

9. From inside the car, use a 3/8 socket extension or something long to drive the bolt into the spilined hole.

10. Start tightening the nut to pull the bolt into th splines, and then jack the subframe up to the body. Remove the started nut, replace the support strap on the bottom and tighten.

Done!

IMG_7642.jpg

Next up, trailing arm bushings... Can this be done with them IN the car??

More on that at a later date?

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Next up, trailing arm bushings... Can this be done with them IN the car??

Not fun, but I've done it... get two piece urethanes for easiest install. I got one piece ones from BMP, and they were a huge pain to squeeze in.

Cool..I already picked up stock replacements.. While I understand it has torsional advantages, I'm not real big on urethane...?

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Next up, trailing arm bushings... Can this be done with them IN the car??

Not fun, but I've done it... get two piece urethanes for easiest install. I got one piece ones from BMP, and they were a huge pain to squeeze in.

Cool..I already picked up stock replacements.. While I understand it has torsional advantages, I'm not real big on urethane...?

Ohhh, then you might be better off pulling the trailing arms and just doing it on a bench. One side didn't want to go in for me, and I did that. We devised a way of putting a giant bolt thru with washers on each side, and used an impact wrench to squeeze them together. I'd imagine rubber ones would be similarly difficult.

The polys sure do make for crisp handling, and the initial squeaking goes away so that they are completely quiet, but the ride is quite harsh. For just myself, I don't care, but the lady isn't very happy with my suspension at all.

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Actually, I went and got it for you.. If your car is lowered and has significant negative camber, while you're in there, flip them over and side to side. You can gain back a few degrees of camber for free...

ummmm, flipping does not gain back a few degrees of camber. it might gain back a couple TENTHS of a degree.

(cough). That's what I was thinking when I typed that.. Tenths! Sorry gents.

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  • 10 years later...

Love this forum! The knurled bolt on the passenger side has chewed up threads at the end so I can't put the nut on. Even I can push the bolt up to replace.

Thanks for the info! (11 years after you first wrote it)

 

Dennis

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