Liftgate or Liftglass Rattle Sound

Some 2021 Tahoe, Suburban, and Yukon models may have a rattle sound at the rear of the vehicle. The sound may be from the liftgate or liftglass.

There are several areas to inspect for possible repairs of the liftgate or liftglass.

Hinge Pins – Open the liftglass and inspect the C-clips on the hinge pins. The C-clip should be in the outboard slot (Fig. 13, #1) for the driver’s side hinge and the inboard slot (Fig. 13, #2) for the passenger side hinge. If a C-clip is not in the correct slot, remove it and reinstall it in the correct slot.

 

Fig. 13

 

Defroster Tab Covers – Inspect the rear window defroster tab covers (Fig. 14, #3) for any rattling. If the covers are loose, re-snap them into position.

 

Fig. 14

 

Rear Spoiler Fasteners – With the liftglass open, check that all fasteners that attach the spoiler to the liftglass (Fig. 15, #4) are properly torqued. Refer to the appropriate Service Information for the correct fastener torque specifications.

 

Fig. 15

 

Liftglass Latch Opening – Apply GM Super Lube to the liftglass latch opening (Fig. 16, #5) using a small brush.

 

Fig. 16

 

Liftglass Seal – Inspect the liftglass seal to ensure that it is properly seated onto the liftgate flange. (Fig. 17, #6)

 

Fig. 17

 

Liftgate Movement – With the liftgate closed, push on the bottom of the liftgate. If the liftgate has fore/aft movement, adjust the liftgate striker forward 1.0mm. (Fig. 18, #9) Also check that the striker is centered in the liftgate latch opening. Refer to #PIT5768 for the procedure to adjust the striker.

 

Fig. 18

 

After performing these repairs, verify that the rattle sound has been corrected.

Liftglass Latch – If the rattle sound is still present after making all other adjustments and the sound has been isolated to the liftglass, remove the liftglass latch and slot the mounting holes 1.5mm to move the latch forward. (Fig. 19) Refer to #PIT5768 for additional information.

 

Fig. 19

 

– Thanks to Jim Will