Some owners of E38s, E39s and E53s may complain of a squealing, groaning or grinding noise when turning the steering wheel.
CAUSE:
The plastic slip ring assembly that fits onto the steering shaft inside the rubber boot where the shaft passes through the engine compartment bulkhead can score, causing a noise as the shaft turns. This scoring is caused by a problem between the two white slip rings and the fixed collar of the ring assembly.
CORRECTION:
Slip ring assemblies made from improved materials are now available. The improved parts can be visually identified by the black plastic internal slip rings; the earlier rings were white in color.
In case of a customer complaint, check if the noise is coming from the joint inside the rubber boot at the bulkhead. If this is the source of the noise, replace the plastic ring(s), P/N 32 31 6 759 546. (E38 and E39 require one, E53 requires two.)
SERVICE PROCEDURE:
1. Remove the lower steering column, per the repair manual, section 32 31 070.
2. E38 and E39: Mark the inner and outer shafts and pull them apart. Slide the plastic ring assembly off the shaft, and install the improved part. Align the marks on the shafts and reassemble them.
3. E53: Slide both plastic ring assemblies off the bottom of the shaft.
Technical service bulletin courtesy of ALLDATA.
For additional information, visit www.alldata.com.