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Old 07-31-2013, 09:06 AM
ngcreese ngcreese is offline
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Join Date: Jun 2010
Location: Germantown, MD
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Wink Broken rear springs swapped out

Swapped out both rear springs yesterday. Put in Suplex HD progressive rate OEM ride height springs. Long story short... they feel GREAT! In fact it looks like what I thought was a worn out suspension system was actually the fact that I was riding on the stiffest part of my old broken springs. The vehicle lifted by an inch on the driver's and half an inch on the passenger side. Not too surprised, since the driver side spring was snapped top and bottom. The passenger side spring was only snapped at the bottom.

Removal and installation required the use of jack stands, a heavy duty hydraulic jack, torque wrench, spring compressors, an impact wrench and cargo straps. I'll put in a more complete description later. For now the most interesting points:

I used the flat metal structure just in front of and under the rear diff as the rear center jack point.

I used pieces of scrap wood as a buffer between my jack and parts of the under body.

For removal, the swing arm and hydraulic jack was used as a spring compressor along with 1" wide cargo straps wound 4 or 5 times around the compressed coils to hold the spring in it's compressed state.

For installation, actual spring compressors were used to compress the new springs. Cargo straps were used to hold the coils compressed. This made the install extremely easy.

Rear lower shock bolts were tightened to 88ft/lbs (119Nm).
Found the shop manual after the job as done. It specs 100Nm tightening torque for the bottom shock bolts, but I'm not going back under there to un-tighten & retighten those bolts.

Here's some pics:

Getting ready for the job...


Scrap wood as buffer on jack and jack stands



Center rear jacking point... not the diff but structure surrounding it, near the front of diff.





I started the work before the springs showed up via UPS....


...and then the UPS truck showed up.


One method for removing an old spring involves using the SUV's jack to pry to swing arm open. It only works if your old spring is short enough to be pulled out. This spring was snapped at the top and bottom, so it was possible. There's a limit to how much you can pry the swing arm open, due to the CV axle and anti-sway bar being in the way under the swing arm.


Old spring vs new springs.


My neighbor lent me his spring compressor, when I couldn't find mine. However, the hooks on his were not large enough to handle the thicker segments of spring coil. So I ended up buying a new compressor set from sears.


At this point I've used the sears spring compressor to compress the spring and bound it with a pair of cargo straps making the spring short enough to slip into place...




Once in place and with the jack supporting the swing arm, I pulled the bow open on the bound spring and it expanded into place.



Now for the passenger side. Here the spring was longer so I just went to compress the old spring in place using my hydraulic jack, then bind it with cargo straps.


Once bound, I released the hydraulic jack and slipped the bound spring out. I then clamped it with my spring compressor, released the straps and finally decompress the old spring.


New passenger side spring compressed with sears compressor.


Then bound with cargo straps...


And slipped into place.




The SUV is now level front to back. Also the ride is REALLY plush, yet firm! I'm super satisfied, so much so, that I've decided to leave shock/strut changes for next year.

__________________
'07 e83 x3
'91 e30 325i



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Last edited by ngcreese; 08-03-2013 at 08:03 PM.
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