G55 AMG 4x4 Squared

I know, there was never a 2011 AMG G55 4x4 Squared, but it would be cool right? In February of 2018, I found a low mileage G55 at the local Mercedes-Benz dealership.  I had driven a supercharged 5.0L Hand-Build V8 G-Class before and was blown away by how the supercharged powerplant propelled the 3-ton truck down the highway.

For some reason, 500HP seems to be a sweet spot for me. Just enough power to make your gut have that WOW feeling, but not so much that you lose control. I've got a Saleen Mustang, a 2020 Corvette C8, and an LS-powered 1978 Corvette all with about 500 HP. The naturally aspirated hot cammed 6.2L LS mated with a close-ratio manual 5-speed is a thrill to drive. The supercharged 4.6L in the Mustang sounds amazing and the C8 takes off like a rocket. I know turbos are all the rage and the current twin-turbo setups are amazing, but there is something so smooth about the power curve on a supercharger that comes close to the feel of a naturally aspirated engine. But I digress...

The G55 is a blast to drive but it was set up for highway use. To me, the G-Class was designed to be driven off-road, and turning it into an urban cruiser just did not feel right. So with power to spare, I decided to turn this G55 into the truck it was meant to be.

The build includes Tibus Portal Axels, Tibus 18" Bead-Lock Wheels, Nitto Ridge Grappler tires, King Shocks, Letech Roof Rack, and a front-mounted Smittybuilt Winch. Customizing any car comes with some give and take. The positives were improved ground clearance and better off-road capability will come with some negatives like decreased highway performance. Some I did not know about. In the coming weeks, I'll provide detailed reviews on each of the upgrades, for now here is the Reader's Digest version:

Tibus Portal Axels: I like the added ground clearance and wider stance, but it came at the cost of less crispness in handling. Off-road the added clearance is AMAZING. It is almost like you don't have to pick your line, just drive. One thing that kind of bothers me is a slight rocking when stopping. Additionally, there is a gear reduction that makes the speedometer read about 10% fast. Nobody can tell me how to adjust the computer to compensate, but I'm thinking a 37" tire would take care of the problem. I'm not super impressed with the installation from my builder as they seem to seep transmission fluid.


Tibus Bead-Lock Wheels: Short answer, I don't like them much. Two reasons, they are HEAVY and impossible to balance. Getting the TMPS to work is also a challenge and they are difficult to get airtight. They are nice to air down but honestly, you can air down somewhat with stock wheels and be OK. After about two months with shaking every time I got up to 70 MHP, I replaced them with a 20" AMG wheel and I'm much happier. The AMG setup works well enough off-road and is great on the highway. Now I can get up to high speeds again and have a smooth ride.

King Shocks: Love these. Having a shock that is adjustable is so nice. Yes, it would be great to be able to adjust the ride from inside the car like the 4x4 squared, but just turn the knob on each shock and I can go from a stiff highway setup to a soft off-road set up in about 30 seconds. With the external reservoir, they seem to hold up under punishing use.

Ritto Ridge Grapplers: Exceptional off-road tires, horrible in the snow. I've used the Ridge Grappler in mud, sand, rocks, climbing "waterfalls" and more. They are even fairly good at highway speeds. Not too loud and handling is good. My problem is I live when it snows, a lot. They are on the verge of being useless in the snow. The Continental Terrain Contact is a first-rate SUV tire and works great on the road. So I've got the Tibus wheels setup with the Ridge Grapplers standing by when I need some off-road fun.

Smittybilt Wench: I know this is not a big name brand wench, but the Smittybilt 97510 X 2O Waterproof Winch performs very well! I've pulled everything from a Jeep to a G-Class to a Dodge 3500 HD with a trailer out of stuck situations with no trouble at all. As heavy as the G55 is it makes a great truck to wench from. I LOVE the wireless remote control. For the G55 I used a Thor wench mount to simply mount the wench to the existing Bumper.

Roof Rack: The Letech Austrian-made rack that comes on the PUR and Professional G-Glass sold in Europe. I like the look of the rack, the build is amazing and it is very functional, however, there is a ringing sound within I close any door and there is an increase in wind noise. Also with top mound antennas for satellite radio, there is a reduction in reception quality. Oh - the sunroof is now useless unless you want to look at the bottom side of the rack. I suppose I could remove the front sheet metal for a nicer view. It is very flat on top, you can basically walk on the top of the truck and the tie-down points are generous. I love the rack, but at almost $7000 it is pricey! I suggest purchasing from Bill Rader out of Las Vegas.

I'll start working on some detailed reviews on each of the mods and provide more information and hopefully allow anyone wanting to trick out their truck some first-hand experiences. Feel free to ask questions at any time.

Rust Bucket

Puch-G Without Fender, Grill, and Bumper

The early W640 G-Wagons are prone to rust. Starting in the early '90s the factory started doing a much better job with rust prevention of the body and frame but those of us with early models must use wax behind the body panels to fend off the ravages of rust.  Even then, after years of water and for trucks in snowy environments, road salt will take a toll on the bodies.

My truck was starting to show some signs of rust, so I found a local body shop that specializes in auto restoration and dropped off my Puch-G.

After the inevitable "wow that is a cool car" they asked what I wanted to be done. I told them that I was not looking for a show car, just to get the rust under control and get it protected so I can drive it around without worrying about the body acting like a sugar cube in a cup of coffee.

G-Wagon Rust Repair

I stopped by 3 days into the work to give it a quick look over. They are doing a fine job cutting away the rust and welding in new metal. From what I can see it will be good as new in no time. Check out the rust that was cut away from behind the front of the wheel and the correct way to weld in new sheet metal.

I'll keep you update with the progress as work continues. 

Heater Fan Motor Replacement

When I was doing the test drive for my Puch-G I noticed the cabin fan did not work. "No big deal," I thought to myself. - it is probably a fuse or a defective switch. Even if it was the motor, I had replaced cabin motors in my MG-B and Jaguar MKII so how hard could it be?

Some quick troubleshooting with a volt-ohm-multimeter confirmed the switch was getting power, working and it was probably the blower motor. So what if it needed to be replaced, no big deal because I've done it before. I was right... and wrong: replacing the motor is very easy, getting to it, not so much.

My Puch-G is an old Austrian Military G from 1991 and since it was a radio truck, it features a 24v electrical system so when I called Sean at EuroTruck Importers and he said he had a Bosh 24v motor PN 0130007004 in stock I was worried that it would be hard to find later so purchased it for $135.

That Bosh blower motor sat on the shelf for almost two years before I got the nerve to replace it. Asking around about replacing the motor, everyone said it was no big deal, "you just have to pull out the dash." After three days of work, I'm going to tell you not only do you have to pull the ENTIRE dash, trim, glove compartment, gauges, vents, handle, center console, steering wheel, windshield support (my windshield folds down), switches, turn signals, heater ducts, metal dash, and the heater. You see the cabin fan sits in the middle of the firewall between the air-intake and the cabin.

It is not hard work, it just takes a LOT of time. I'm not going to go through the process step by step because the W460 G-Wagons were made for well over a decade and military versions like mine even longer. So dash configurations differ over the years. What I want you to know is that the process is not hard but is time-consuming. Easily done by anyone with medium skill level and simple tools.

As you start pulling the car apart, follow these simple rules:

• Remove the negative connector from your battery prior to doing anything.
• Take photos as you go to document where everything goes.
• Mark the screws and bolts so they go back to the correct place - poking them into cardboard with Sharpie notes works great.
• Don't force anything, most parts come out easy, so if it is not coming out, look for more screws.
• The flexible ducting will easily break, so just order some before you get started.
• While in there, plan to put some Dynamat and Dynaliner on the firewall and on the inside of the dash to quiet things down.
• Blow everything out with compressed air, and do a deep clean before putting it back together, I used dishwashing liquid bath and a clean water rinse.



W460 Dash Removed Showing Heat Exchanger

• Use Deoxit on the electrical connectors.

The photo here is what it should look like after pulling everything out. That dust you see is over 30 years of dirt courtesy of the Austrian military. In the middle is the entire heating and blower unit. You will need to remove the side plenum ducts shown here prior to removing the center unit. There were three Phillips screws on each side. Don't attempt to remove the top plenum as it is difficult to remove and the unit comes out nicely with the top attached.

You can see the flexible side and windscreen ductwork has been removed on the right and the left it still connected. You will need to remove the top dash prior to getting the heater/blower out. There are two small Phillips-head screws in the back holding the top dash in place. Remember to remove the coolant hoses on the right side. Turn off the heat valve and have a small container handy as you will get some coolant spilling into your cabin.

Once out you will need to take the heat exchanger apart to get to the fan motor on the backside. This process is easier if you heat up the box a little with a hairdryer and use some trim tools to pry the tabs out while pulling the back off. Be careful the tabs are brittle and will break.

Once out you will see the fan and in my case the resistor for low-speed operation. My Puch-G only has two speeds later W460 trucks feature a three-speed fan. You can remove the cables by unplugging them from the motor, they are polarized so there is no way to plug them in wrong. Remember to spray the electric connectors with Deoxit.

Remove the two spring clips holding the motor and slip it out toward the back with the fan attached. The fan is very difficult to remove, but it is held in place with only friction, no glue, clips or screws. Be careful with the fan because you will notice some clips on the blades that were put in place to balance the fan; consider using some tape to hold them in place until after you get it installed again.

Clean everything very well. The new motor came with a plastic cover that made me think it would not fit, but the cover just needed to be removed. Also, on the back of my old motor is a small plastic cap covering the rear bearing, I carefully removed it from the old motor and snapped in on the new one. I slid the motor in place, installed the clips that held the motor secure, electrical connectors then finally mounted the fan. Once again the fan held in place on the spindle with friction and don't push it too far in as the fan will scrape against the housing. I tested the fan with a motor prior to putting the heater box back together.

I pulled out the heat exchanger (it looks like a radiator) and blew it with compressed air I also replaced the foam holding the exchanger in place as it was deteriorated. All the plastic pieces got a bath inside and out then I put the heater box back together.

Cleaned and Mounted Heat Exchanger

Then I simply reversed the take apart process carefully following the order; hint: leave the glove box, steering wheel, gauge cluster, and speaker cover for last - even after installing the center console. Here is how the cleaned heating unit looks installed before putting the dash back in. No more Austrian dust!

I also changed the heater valve cable. These are notorious for getting hard to adjust over time and with everything apart super easy to replace and adjust.

While all the parts were out, I took the opportunity to thoroughly clean the dash parts and put some Dynamat on the backside of the metal dash to kill that tin can sound. I also used some rubbing compound to clean up the painted pieces and polished them with car wax. All plastic pieces got a bath before putting them back in as well.

Some of the foam that was between pieces needed replacing so I used some adhesive weather stripping to replace the foam with new. Now the truck has a working fan that blows clean air and my dash looks good as new. Just remember - this project takes TIME. After 2 years of procrastination, my defective motor is finally replaced and the heater blows clean air.