My rear suspension is sagging

Chris Hobbs · Post by **Chris Hobbs** » Tue Aug 19, 2003 11:00 pm

On one of my 412 wagons, I just replaced the kaput KYB Gas-a-just KG5531's with a new pair of KG5406's. While this was a big improvement in the stance, the rear still looks around 1-2 inches too low. Is there anything that can be done with the springs at this point? Is there a source for aftermarket springs or beefier springs?

Or....I notice that on my second 412 wagon, which still sports the original Boge shocks, the PO put spacers in the springs to fix rear-end sag and the effect is very good. Is spacers the answer? Has anyone else out there resorted to using spacers?

Any suggestions, tips, or lessons learned would be appreciated.

alsehendo · Post by **alsehendo** » Wed Aug 20, 2003 12:50 am

Ray will probably confirm this is normal, front end sticks up unless you load it down--it was made this way. Look at other posts about lowering the front with his Audi shocks.

raygreenwood · Post by **raygreenwood** » Wed Aug 20, 2003 7:35 pm

Believe it or not...I have rarely found the 411/412's to have sagging springs in the rear...even when they have sat for a while. The shocks are not really what causes it to sag...if it does. As the previous post noted...the front end is the culprit. It was designed high from the factory, giving a tail down appearance. When the shocks wear in the front...the stiffness of the springs causes the front end to rise about 1/2" higher because there is not enough seal left at the top of the stroke to keep the strut from fully rebounding. Ray

Chris Hobbs · Post by **Chris Hobbs** » Tue Sep 02, 2003 10:11 pm

Wait a minute, do I understand this correctly--did you say the real answer could be that I need to replace my front strut cartridges to bring up my rear end?

OK, I'm game. I was given a set of unused KYB KC4017 cartridges last year, maybe it's time to put them to use.

raygreenwood · Post by **raygreenwood** » Tue Sep 02, 2003 11:13 pm

Well...yes and no. It is possible that there is a wee bit of sag in the rear...but I doubt it. The front was set up to be about 3/4" taller. that does not sound like much ..right? It is. Think of the center of the rear axle as the pivot point of a right triangle. The long leg is the straight line between the front and rear tire tops...OK?...Then the unpright goes straight up to ....say...the edge of the front fender as it rises over the tire. Drop the hypoteneuse back down to intersect where the bottom edge started in the back. Over the 9 foot or so.....that 3/4" is a hefty angle. I think about 3-4*. Try this. Put 100 lbs in the front trunk and bounce the shocks 5 times. Then look at it again. Better? Probably not enough. Put in another 100 lbs of something. It will probably take about 250 lbs. The thing will look rockin....level! Look at the size of that trunk! It was designed to be loaded...and sit level. They did not think about what happened if you did not run with a loaded trunk.

Sadly though...if you keep it loaded like that, it will waste the stock shocks in about 25K miles.

Try this though. since you have some stock struts.....take your dremel tool...and cut off the "cone" or foot from the bottom of the striut cartridge. Thats good for about 5/8". Make a spacer from an old bearing race or a piece of pipe to put on top, so there is no slack between the capand the cartridge. Wrap rubber sheet or inner tube material around thye shock body as a "stuffer" to keep the strut cartridge from "twitching" around in the tube. They all didd this. You shoul do this either way. If you have a 411...or the long pin shock...leave out the spacer shim...that slips around the shaft. Thats good for about 13mm. The shaft will stick up farther...and the spring compression will be about 2-3% more..but it should be level at that point. Ray