09-18-2012, 08:50 AM
Wrenchin' fool ...
Join Date: Jun 2004
Mein Auto: e39 528it
Lots of touring 6s (528it and 525it) have rear air suspension. It was an option. None of the 540iT tourings have rear metal coil springs, they have SLS (self leveling system) or EHC (electronic height control) only.
I like the 6 vs. V8 better model because it doesn't have the air suspension in the rear along with the known to fail rear carrier bushings...
Besides replacing the rear sport air springs, (leak after X years of use / 120k +/- miles) I haven't had a problem with my system going on 12 years and 207,xxx miles. Note: there are different part numbers for sport versus non-sport rear air springs and for left versus right in each kind.
The part numbers apply to 528it, 525it and 540it with SLS/EHC.
Non-sport Pneumatic Spring, Left 37121094613
Non-sport Pneumatic Spring, Right 37121094614
Sport Pneumatic Spring, Left 37121095081
Sport Pneumatic Spring, Right 37121095082
The rear carrier bushings = subframe bushings = are the same on 528it, 525it and 540it.
Part # 33311094036
They are liquid filled from BMW to dampen NVH (noise, vibration and harshness) and can be replaced with the same or Meyle makes a solid rubber replacement. I have replaced mine (with BMW supplied OEM) and several other sets (using OEM or Meyle) on other enthusiasts tourings. It is an afternoon job at most and the touring needs to stay up on jack stands preferably overnight to let the lube on the bushings evaporate and for the bushings to set.
The rear carrier bushings tend to fail sooner on the 540iT due to the torque/hp of the V8 versus the I6s. Typically, 540iT owners need to drop a carrier bolt and large washer to inspect their bushings for failure around the 100k mile mark. I6 touring owners seem to get a little more mileage (~ 120k miles) before their rear carrier/subframe bushings fail.
Remember: on the touring the entire rear suspension is captive to the subframe. Meaning, besides the drive shaft attaching to the rear differential, ALL shock and road force transfers through the rear carrier/subframe and then the bushings eventually to the unibody. That is why the rear carrier bushings on the tourings are a key part of the rear suspension "system". E39 sedans rear shocks/towers attach directly to the unibody.
I have the Franklin E39 touring subframe bushing removal tool for rent if you need it. Lots on this forum and others have DIY/used it over the years and we have all saved a boatload of $$$ versus having an Indy or dealer do the work.
2000 528iT Sport 5M (mfg. 5/1999) ~ 1990 325iX 5M
BMW CCA member #130075