I installed the new shaft on my '01 SSEi today. Thought you would be interested in seeing the major design update over the old OEM style.
The major changes I see are:
1. The addition of a reinforced isolation "coupler". This is a MAJOR change, I think to isolate noise and vibration from the rack.
2. The "slip" shaft starts out round but is modified by a "flat" on each side (that'* where the new double-D designation comes from).
3. The shaft itself is attached to the steering gear side of the assy., unlike the original, which is attached to the steering wheel side of the assy.
4. The revised assy. appears to be beefier than the old one.
Installation was pretty much the same as with the old shaft but..............
- the large coupler makes it slightly more difficult to get the shaft through the boot/firewall.
- the coupler, as I expected, initially caused a rubbing noise as it rubbed against the clear vinyl plastic boot. I fixed that by getting back under the dash and rotating the boot until it "cleared the boot.
All is smooth and quiet again. PS- The revised shaft, like the old one, is manufactured by Delphi, right here in Dayton, Ohio. PSS- Ordered through gmpartsdirect, the shaft was shipped from a Cadillac dealer.
The part in non-refundable so make sure you know what you are ordering.