There are several GM Technical Service Bulletins you can refer to for a leaking Folding Top:
1. TSB is 07-08-57-003 "Water Leak in Trunk when Parked on Hill/Incline" and affects 04-08 XLRs
I contacted the folks at Kent Automotive and they have the proper automotive shim stock available. They say the part number is often wrong, even in GM's leak repair procedures.
The correct part number is: P46475. Pictures are posted to show the location and length of the shims.
My POC at the time was:
Alicia Walker - Web Customer Care Rep
Lawson Products Inc.
Customer Contact Center
Phone # 1-866-837-9908 Ext 7334
2. TSB is 05-08-57-005A Dated 8-18-2006 and affects 2004-2007 XLRs
Condition: Water entry over the wheelhouse traced back to the joint between the rear compartment weather strip and quarter belt weather strip.
Correction: Separate the joints and lift each end 50-76mm (2-3 inches) enough to apply 3M Bedding and
Glazing Compound so that it extends to both ends of the weather strip and will cause slight squeeze out when reinstalled. As you reinstall the weather strip, be sure the smaller weather strip is fully inserted into the opposite weather strip. Work the weather strips onto the flange and towards each other to ensure a tight joint when finished.
There's a line drawing of the long, U-shaped weather strip that follows the contours of the trunk perimeter lifted above the rear of the car.
Here's a link for the Bedding &
Glazing Compound:
http://www.shop3m.com/62556252096.ht...W_3MAAD_GS-Tab Sold in 1 gallon quantities in tube form.
Kicking it up further, is the next section, detailing a known design deficiency:
Condition: Water entry over wheel house and traced back to quarter belt cup. The cup drain is not large enough to drain adequately and floods over the dry side of the
sealing system, which allows water to enter the trunk.
Correction: The cup joint is located at the rear of the quarter belt seal and it looks like a trough. This area is where the roof panel lower weather strip contacts when the roof is closed. The area just forward (toward front of car) of this cup is the "wet area" and to better manage the water into this wet area, a strip of foam must be added into the rear roof panel lower weather strip where it contacts the cup. Cut a strip of adhesive backed foam Kent Adhesive - Back Shim Stock P/N P46475, 60mm x 15mm (2 1/4 in x 5/8 in). Clean the area of the roof panel lower weather strip where the foam will be added using de-natured alcohol before installing the foam strip to ensure adhesion. (--At this point it references two illustrations that words just can't describe adequately.)
https://www.*******.com/forums/images/smilies/willy_nilly.gif
This fix was done to my car and needs to be replaced occasionally due to top movement that loosens the foam strip over time. --It's a good thing the foam strips come in 50' rolls!
https://www.*******.com/forums/images/smilies/smile.gif
And then, almost as an afterthought is this little bombshell that could seriously dent your pocketbook if you were cursed enough to have this happen:
https://www.*******.com/forums/images/smilies/reddevil.gif
Condition:
Water entry into rear tubs located behind the rear wheelhouses traced to the area behind the rear tail lights.
https://www.*******.com/forums/images/smilies/pat.gif
Correction: There are a number of panels that are bonded together in this area. If entry is traced to this area, remove the rear tail lamp on the affected side to help gain access. Use Kent Seam Sealer, P/N P10200 to seal the affected joint. It refers to an illustration with an arrow at either side of the rear of the car (with the tail lamps removed) that point to the outside, lower edge of the surface where the tail lamp housings mate to the car's body.
And then, if you were wondering why you bought so much Kent Seam Sealer in the first place, this follows:
Condition: Water entry into the rear compartment. Water may be present on the sill of the lower rear compartment opening (near the latch). Water may be seen dripping from the rear compartment lid inner trim at the lower corners.
Correction: Seal the area of the rear compartment lid inner and outer panels at the outer most vertical seam (between arrows - either side). The seam is on the inside of the
rear compartment lid. Then it refers to an illustration that points to the top/rear corners and lower rear corner of the trunk lid on each side.
And lastly, is included something ALL XLR owners should do:
Inspect the rear tub drains (This is incorrect since only the tub on the driver's side in my vehicle has a drain) to ensure they are clear of any obstructions. Inspect to be sure there is no loose material in the tub that could cover the drain on the inside of the tub. (--This really wouldn't matter if we didn't have to worry about water intrusion in the first place!)