Anyone replaced a rear hatch/tailgate on a GMT900?

[RichardCranium]

Curious, as I am likely going to buy a replacement for my Tahoe. The hinges are very easily accessible, my curiosity has to do with the wiring harness and rear wiper connections. I would hope they were fairly easily accessible, but just wondering if anyone was familiar and might have some lessons learned. I do expect some body shims under the hinges, not sure what else to expect......

 

[MickeyD]

I haven't done one on a GMT900, but I did on a GMT800. It was very straightforward. At least with that truck, there was the rubber boot covering a single connector for all the connections. And I think the only other thing was the rubber line for the rear washer fluid. I'll take a look, but I expect it's probably very similar for the newer trucks.

 

[Leo1103]

Not hard to do, I helped @Doug118 pull his a few months ago so we could deaden it. Definitely remove the hinges from inside the body. I wanna say there is a plug above the headliner in the rear to disconnect everything

 

[swathdiver]

Curious, as I am likely going to buy a replacement for my Tahoe. The hinges are very easily accessible, my curiosity has to do with the wiring harness and rear wiper connections. I would hope they were fairly easily accessible, but just wondering if anyone was familiar and might have some lessons learned. I do expect some body shims under the hinges, not sure what else to expect......

FF to 14:52 in this one:

FF to 6:45 in this one:

There is probably more video from Vehcor on this subject, I just don't remember.

 

[RichardCranium]

FF to 14:52 in this one:

FF to 6:45 in this one:

There is probably more video from Vehcor on this subject, I just don't remember.

Solid! I searched to the bottom of YT for videos with a Tahoe, total disregard to searching any other brands on the same platform. Thanks!

 

[swathdiver]

Solid! I searched to the bottom of YT for videos with a Tahoe, total disregard to searching any other brands on the same platform. Thanks!

He's done videos on a few 800s and 900s and they give great insight into how our trucks are built and assembled.

 

[RichardCranium]

In case anyone stumbles upon this thread, here are a few tips and lessons learned:

• if you are pulling a tailgate from a junkyard and don't feel like hanging around too long, pull the whole assembly off with the glass attached. In other words, don't take the time to remove the glass, then everything else.
• if the donor truck has no way to power the chassis to unlock the rear tailgate, there is small manual lever right beside the latch. Of course the interior trim on the hatch must be removed, which technically you can only do when the hatch is open. So you might have to cut the interior panel, if so do it near the latch (since you are inside, make your hole a tad right of the actual latch, because the lever is on the right side). FYI there is also a manual lever to pop the glass as well, it hangs straight down from that latch.
• No matter how you take apart the donor or how you install it on your truck, you are going to have to remove the taillights, both upper exterior D-pillar pieces, the upper horizontal D-pillar trim (that goes from left side to right side), and both upper D-pillar interior pieces.
• The wiring harness and the rear wiper fluid line are under the headliner, but you can access them with the aforementioned parts removed, and do it without damaging your headliner. I have big hands and managed to tackle this.
• The biggest PITA of the entire swap job falls within 2 parts, and it depends on your truck and your donor tailgate if you need to swap them: the trim that carries your license plate lights, and the rear windshield wiper arm motor
• The trim above your license plate has 4 studs on the back, that feeds through the tailgate and secures with 4 regular 10mm nuts. The problem is, and @PPV12HOE verified as well, when people replace these they overtighten the hell out of them. When they do that, they break the studs off in the trim (plastic). To get the broken trim off my donor tailgate, I had to use a 10mm wrench on the nut inside, and hold the end of the stud with a pair of vice grips. It wasn't fun. If you swap this trim, tighten down these nuts with your fingers, then it them with a wrench just to make sure they are snug
• The rear windshield wiper motor attaches in 3 points: the exterior, once you pop the wiper arm off, there is a large (about 27mm) nut that comes off pretty easily, then there are 2 studs on rubber isolaters inside the door chassis. In order to remove these 2 points, you need a smaller than normal 10mm wrench and a really good flathead screwdriver. The flathead is to turn the stud down and back it out of the nut. You can really make your life a lot harder here with a cheap screwdriver. As a former BMW tech, this is one of those jobs where it pays for itself to have the nice tool truck screwdrivers with the hardened alloy tips.
• I bought a donor tailgate complete with the glass and the hinges from the donor as well. When I went to install my original glass into the donor tailgate, there was one dowel that would not properly line up no matter what I did. Easy fix, align the dowels that you can, then grab a large pair of channel lock pliers and pop the last one in by force.
• If you removed the hinges from the donor to install on your truck, you are going to have to adjust them. It's fairly easy though, thankfully. Just be prepared and have both of them loose enough to move by a little force when you go to install the assembly into your truck.
• If you swapped your glass into the donor tailgate, you are likely going to have to adjust the latch for that as well. My glass would sit flush but wouldn't latch. There are a couple of E-torx bolts to loosen, and you can slide the latch to adjust depth.
• There is one thing everyone can take from this, and its how to properly install the rear taillights. They don't just slap in and bolt up, ask me how I know. I've been riding around with a noisy and squeaky rear on this truck for months. I also noticed when I closed one of my rear doors, it made the taillight on that particular side squeak. There are 2 aligning dowels that pop in when installing the light assemblies, then 2 philips head screws hold it in place. You HAVE to put the lower dowel in first, to get the light assembly to sit properly. This is a very simple task that can be overlooked or shunted by hardheaded MF'ers like me. I certainly don't "know it all", but after turning wrenches for over 15 years for a living, 10 of those in a high line, you'd think things like this would come easy. Sometimes things get overlooked.

I'll probably add another line or two later, maybe @PPV12HOE can add one or two also.

 

[PG01]

Ever notice the little ‘hole’ or notch at the bottom of the interior panel on the liftgate?
If you drill a hole in that location that’s where the manual latch release is.
I learnted that here.

 

[RichardCranium]

Ever notice the little ‘hole’ or notch at the bottom of the interior panel on the liftgate?
If you drill a hole in that location that’s where the manual latch release is.
I learnted that here.

Nice! Even though I am far more intimate with the tailgates on a GMT900 now than I ever want to be, I don't even recall seeing that.

 

[PPV12HOE]

Ever notice the little ‘hole’ or notch at the bottom of the interior panel on the liftgate?
If you drill a hole in that location that’s where the manual latch release is.
I learnted that here.

It's more like a lil dimple on mine... @RichardCranium
Nice write up by the way... I got nothing to add... you hit it all...