rear springs

[trucker677]

I am changing the rear shocks in the car, I looked at the manual for removing them, I am confused on something. it says to undo the three nuts located in the rear hatch, undo the bolt for the sway bar (i think that is what it is) and the bolt for the bottom of the shock. My question is at the top of the shock there is a nut, if I undo that nut will the spring come flying out, I am thinking yes it does but I want to make sure, because murphy is never on my side. If I am right I undo the three nuts and the bottom nut on the shock and the sway bar bolt and the shock/spring assembly should come out in one piece and I take it to my spring shop and have them change it and install it and do up all the nuts and bolts, am I missing anything. Also does anyone know the torque specs for the nuts and bolts if any, any tips or advice is greatly appreciated.

[rcrone928]

What ever you do, don't remove that center nut till the whole unit is out of the car! You may have a hard time getting the pin that holds the shock and lower control arm. Many write-ups on this if you do a search, Good luck.

[stepson]

If you undo the center nut on top of the assembly, you should be able to lower the shockindependent of the spring. I have never done it that way myself, but will try it that way at some point. I have always removed the whole assembly.
Here's your torque specs courtesy of Rob Edwards and AO:

REAR SUSPENSION
crossmember to body-lateral M10 x 75 63
crossmember to body-medial M12 x 1.5 x 45
rear control arm fore mounts 2 x M10x 75, M10 x 50 63
crossmember to tranny M12 x 1.5 x 40 116
Rear swaybar to body mount M10 x 85 63
Rear swaybar to upper droplink M10 x 55 63
Forward rear trailing arm mount to body bolts M10 x 20 M10 x 20 63
Forward rear trailing arm mount to body bolt M10 x 75 x 1 M10 x 75 63
rear upper control arm to crossmember medial bolt M10 x 70 63
rear upper control arm to wheel carrier lateral bolt M10 x 105 63
swaybar to body mounting bolt M10 x 85 M10 x 85 63
swaybar to upper stabilizer bolt M10 x 55 M10 x 55 63
lower rear stabilizer bolt to LCA M10 x 45 M10 x 45 63
axle mounting pan head bolts to tranny output flanges M10 x 50 110
LCA to crossmember (camber eccentric) M14 x 1.5 270
LCA to body (toe eccentric) M12 x 1.5 162
rear hub carrier to LCA (lower shock thru bolt) M14 x 1.5 189
rear axle bolt M22 x 1.5 623
rear upper shock mount studs to body M10 63
ABS sensor to rear hub carrier M6 x 13
wiring brackets to rear hub carrier M6 x 13
e-brake brackets to cross member M6 x 50 7

[georges 928S]

Hi stepson, can you describe these specs in pounds per torque and which numbers to go by or use for torque, for some including me is confusing. thanks Ed.

[neil30076]

The last number on each line is the torque in Nm's. The other numbers are the bolt, or nut sizes.
for example:
rear axle bolt M22 x 1.5 623

this is a M22 bolt, 1.5mm pitch, and requires 623Nm torque.

Per http://www.boltscience.com/pages/convert.htm

1 Lb-Ft = 1.35582 Nm.

BUT -
I believe AO's conversion factor is incorrect, Porsche spec says Drive shaft rear wheel shaft to wheel hub is 460Nm, which is 339 ft lbs. The 623 number is a result of doing the conversion the wrong way!

[trucker677]

I got the assembly off and taken apart, wasn't too bad. Got all the parts cleaned up. I noticed that the adjuster at the bottom of the shock was about half way up. Is that a normal position or does it need to go up or down, I know it is going to be a ball park figure and when I go to get the car aligned they will adjust it to make it to ride height. I just want a close proximity as a starter point. Thanks for the help so far on this.

[trucker677]

anyone??/

[MPDano]

What is the answer your looking for? You can't measure the adjuster nut and where it sit's on the shock since it will ride higher on a old tired weak spring. Are you looking for the stock ride height?

FYI, yes the rear springs are easy to work with, wait till you tackle the fronts.

[trucker677]

after reading your comment I never thought of that, different ages of springs would mean a different heights. I know at some point my springs were replaced, I put my collar about half way up so it will be close to where it was. I will let the alignment shop figure it out where ride height is.

[Landseer]

Springs are coded with paint marks that delineate rates, BTW, and WSM differentiates them. Marks differ amongst years, and different springs are used within years. Three blue stripes on an 84 spring is the stiffest offered from factory that year.

Spring rate degradation aside, you never know what mixing / matching has occurred during the last 30 years of undocumented maintenance.



Get your adjusters clean and lubricated. Clean up threads as needed with jewlers file.
You should be able to adjust ride height yourself using a spanner wrench or motorcycle / atv shock collar adj. wrench.

A write up on rennlist by user "Tony" has pretty good instructions and show how to make a clever gage to check, plus where to measure.

[trucker677]

cool, thanks for the help, I will take a look

[MPDano]

I agree, get it close and threads clean before dropping it off to the Alignment guys. So far both of my 928's had a weak spring. Euro was a rear one and the "S" was in the front.