GL Class (X164) 2007-2012: GL320CDI, GL420CDI, GL450, GL550

Eliminate 3rd Row Seats

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Old Jul 29, 2022 | 06:00 PM
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From: Emmett, ID, USA
2007 GL450
Eliminate 3rd Row Seats

In the interests of my ongoing "weight loss" program for my GL, I decided to rip out the third row seats:


The seats aren't hard to remove. Six big torx bolts on each. I also removed the armrests, to access the shock absorber top nuts and the inside wall of the plastic shell. The seat belts are disconnected, with the seat belt buckles removed. I am unsure what to do with the seat belts; they might make decent cargo holders, but I am skeptical. The tear-apart also yields nifty bolt-in D-rings, which might prove useful.

The folding spring-loaded cover has also been removed. I have plans for it.

The plan is to build a C-shaped frame from angle iron and then install a platform that rests on the prior hinged flap and around the angle iron frame, which will be supported by bolts through the plastic shells on each side. I reckon if I use bed frame angle iron and weld the joints, it will be strong enough to support my weight, and if I align it correctly, will nearly seamlessly join with the second row seats when folded down. Then I can sleep in the back, should it come to that, and store all kinds of unpleasantries in the compartment below.

The platform ends up being 33-1/2 x 40 wide. I plan to join two strips of 3/4" plywood, hinged together, one narrower and married to the old hinged flap. They'll fold up accordion style; otherwise the platform would not clear the ceiling and would be unwieldy. Install some recessed lifting handles, cover the whole thing with black sheet rubber, and I should be good to go.

Ironically, the armrests with cup holders will come back in use; I anticipate wanting to put a beer in there should I end up car camping in this thing.

I do not think a full size spare will fit in there, but certainly stuff like a Hy-Lift jack will. And rope, and rifles, and ammo, you know, that sort of stuff. Regrettably, the bulkhead between the spare tire well and the passenger compartment looks to be structural. It appears thoroughly welded in to the belly and sides.

If you wish to also perform this weight loss surgery, and if you are so inclined, you can remove and sell the seat motors. They fetch about $150 each on Ebay, if in good condition (the plastic gear not stripped!), netting about $125 after fees n stuff. Not bad. I already sold one motor. The switches also eventually sell, but are much less fast of a mover. There is also a tiny demand for the standoff spacers the motors sit on top of. And a near-negligible demand for the headrests. The seats themselves, forget it.

Will follow up with progress on the build-out.

Last edited by eric_in_sd; Jul 29, 2022 at 06:02 PM.
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Old Jul 29, 2022 | 06:10 PM
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Maybe the seat belts would be good dog tethers.
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Old Jul 29, 2022 | 06:47 PM
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NGL450 w/EORP, S550
Wait wait wait…more info needed here about the new back shocks…new tires?
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Old Jul 29, 2022 | 07:15 PM
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Originally Posted by Max Blast
Wait wait wait…more info needed here about the new back shocks…new tires?
Nah just wear and tear. One is leaking. They are about 90k miles old.

It's a good idea to change them preventatively. Otherwise accelerated tire wear can result. You know, cupping.
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Old Sep 29, 2022 | 05:28 PM
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Well, I thought I'd never get around to it, but here we are.

I built a C-shaped frame using bed frame angle iron and two box section pieces from an old Ikea type table I dismantled. Cheap furniture is a great source for dimensional steel!

The box section pieces came with threaded inserts on the end. A M8x1.25 bolt threads right in. With the appropriate holes drilled into the angle iron, the parts are joined: This picture is after I gave it a quick coat of black paint. The frame is 40" wide and 29" long. It will support a 40" x 31" piece of plywood (or two 40x15.5"). I was going to try to use the hinge on the existing holder that presses flaps against each third row seat, but in the end it was simpler to dismount the hinges and cut off the flaps. That way I keep a nice matching 2" of floor surface that already has in it cutouts for the hold-down D rings. One edge of the plywood is supported by the aft bulkhead, so the frame is a couple inches shorter than the plywood. Here is how the angle iron attaches to the box sections, which are 1x1".



I used tubes to match the elevation to the existing and to suspend the frame at the right height. 1/2" plywood matches the height at the rear; the whole apparatus is designed to sit at the right height to match the second row seats when lying flat. A strip of plywood is used to match the final thickness of the floor.


A closer look


First, by reaching inside the interior fender covers, I found suitable locations for the mounting holes. I found three, one as far aft as I could reach, one as far forward as the flat section of cover ran, and the third halfway between. I drilled pilot holes in the frame and then into the cover, being very careful to not plunge into the air lines and wire bundles on the passenger side. I pre-drilled 1/8" pilot / exploratory holes, then confirmed the holes were in good locations. Then I expanded the holes to accomodate 1/4"x5/8" machine screws. Fortunately the inner cover is strengthened by a webbing of support ribs; unfortunately, that means the holes land anywhere from the center of a void between ribs, which is good because it means you can use a fender washer, or bad because the best you can do is get the 1/4" nut in there. It is a dart throw. I ended up using two fender washers, two regular washers, and twice no washer at all.

I pulled the frame out to drill the final holes in it and in the fender covers. A good step drill set is a must. The holes to accommodate the 1/4" screw heads need to be large; the holes inside the box section and the fender cover are of course 1/4". I used a step drill to make the holes in the fender covers, to go in easily and reduce the risk of suddenly plunging in.

.I did the final installation of the frame with the support rods, removing them after installing the screws:


The screw heads are not visible because they are inside the box section.

And here is the finished product with one panel in place:


I may install a single post to go from the center of the bed frame piece down to the driveshaft tunnel. The fender covers are pretty sturdy, though, and the bed frame is obviously plenty strong.

Also, half inch plywood is not very stiff; I am probably going to reinforce these panels with other, smaller steel box section. I have some 3/4x3/4" (thanks again, Walmart Chinesium furniture!) which should do the trick. It is less stiff but I want a folding cover so if I need to keep the cover off temporarily it stows neatly.

When I am sure I have the panels the way I want them, I will cover with sticky sheet rubber from Autozone.

Pretty excited with the results. The cargo floor is flatter and I have extra semi-concealed storage.

Last edited by eric_in_sd; Sep 29, 2022 at 05:38 PM.
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