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Sway Bar Upgrade

My 750iL handles great for a 5000 lb car, but it was known to lean a lot in the corners. After taking my car to the track, I really wanted to do something to improve the handling and flatten the way it corners. Upgraded sway bars were order. They made a big difference in handling and the car corners much flatter. The real test will come when I head out to the track in the spring.

Here is the original 20.5 mm front bar and the 22 mm �sport� bar that comes on late 740i Sport models. It is a direct swap for the factory bar on any E38 7 Series. The only other parts that are needed are new rubber bushings with 22 mm holes in the middle.

Here is the original 10 mm rear bar and the 13 mm �Eastern European� and �Bad Roads Package� bar, which is not available in the US. If your car has a rear sway bar, the new one is a direct swap. As with the front bar, new bushings with the proper sized holes are needed.

Unfortunately, swapping the front bar is NOT an easy job. It takes most of the day and there are no shortcuts. You need to disconnect much of the lower front suspension, unbolt the steering gear, raise the engine several inches, then unbolt and lower the front subframe.

The rear sway bar is much easier to swap. It can be done in about an hour. It only requires unbolting the sway bar brackets, disconnecting the self leveling sensor attachment, disconnecting the end links, removing one wheel and sliding it out the side.

Sway bars were factory installed in the US on all long wheelbase 740iL and 750iL models with self leveling rear suspensions. They were not installed on other models. The possible exception is short wheelbase 740i Sport models. Many published specs indicate that the sport models have sway bars, but owners of 740i Sport models have indicated that their cars do NOT have rear sway bars.

Here is the bracket that mounts the sway bar to the car�s subframe. This shot was taken with the exhaust system removed from the car. This bracket is normally only visible from getting all of the way under the car and looking up.

This is the subframe mounting bracket viewed from underneath, looking straight up.

Here is the left frame bracket as viewed from the center of the car looking toward the left. The camera position was just below the differential.

This shot shows the position of the rear bar as it crosses behind the differential. There is plenty of clearance behind the differential, but the clearance behind the self leveling sensor and the front of the spare tire well �tub� is quite limited. In this picture, the self leveling sensor is bent slightly out of position and the arm that connects to the sway bar is missing. It was damaged when the floor jack slipped out from under the differential as the car was being jacked up.

Unfortunately, cars without rear sway bars do not have rear sway bar mounting brackets. A number of people without rear sway bars have indicated a desire to install brackets and rear bars on their cars. These photos are included to help identify how the brackets are mounted for the benefit of those that may wish to install their own. This picture shows the distance between the bar and subframe that the lower control arm mounts to.

Subframe mounting bracket.

Lower control arm. On the first picture, the end of the tape measure is at the center of the lower control arm bolt.

Lower control arm bracket from the side. (Sorry about the lack of focus.)

Lower control arm bracket from the top. On the last picture, the end of the tape measure is at the center of the lower control arm bolt.

Please browse to the following pages:

1 Introduction
2 In the Beginning
3 From the Front
4 From the Side
5 From the Rear
6 The Interior
7 The Audio Video System
8 Both of My 750iLs
9 May Puget Sound Meet
10 June Puget Sound Meet
11 July Puget Sound Meet
12 Engine and Drivetrain
13 BMW Club Concours d'Elegance
14 BMW Advanced Driver Training
15 BassLink Install
16 Oil Change and Oil Pump Bolt Check
17 Quad Rear Brake Lights
18 Phone Install
19 Jets
20 Strong Strut
21 Eisenmann Exhaust
22 Sway Bar Upgrade