2016 Mercedes G Wagon Front Axles
About this episode
Grease leaking from the front steering knuckles on a 2016 Mercedes G63 leads the hosts into a detailed front-axle walkthrough. They explain how water intrusion around the steering knuckle seal can ruin lubrication, and why the job is more than cosmetic—rusted components won’t seal properly. The discussion then expands to CV joint diagnosis: a torn boot, water contamination, and rusted ball bearings. They also cover how shims set bearing clearance and what noise you might notice when 4WD is engaged.
G-Class Gwagon
"Doing very well. So today's guest is a 2016 G-Wagon G63. What was going on with this incredibly expensive vehicle? The front steering knuckles had some grease leaking out of them."
This is a Mercedes-Benz G-Class G63, the AMG performance version of the G-Wagon. The episode is about a front suspension problem where water can get into a key joint area, causing grease to leak and making repairs costly.
The Mercedes-Benz G-Class G63 is a high-performance AMG version of the classic, body-on-frame G-Wagon. In this episode, the focus is on a front-end issue where the front steering knuckles can let in water, leading to grease leakage and expensive repair work.
front steering knuckles
"So today's guest is a 2016 G-Wagon G63. What was going on with this incredibly expensive vehicle? The front steering knuckles had some grease leaking out of them."
The steering knuckle is a key part that helps the wheel steer and move. If grease is leaking there, it usually means the seals aren’t keeping things out anymore, and water can get in and cause trouble.
The steering knuckle is the hub-like component that connects the steering linkage and suspension to the wheel. If grease leaks from the knuckle area, it can indicate seal failure or water intrusion, which can quickly turn into an expensive front-axle repair.
front suspension and drivetrain
"So this has a very old style, very heavy duty front suspension and drivetrain, almost unfitting for the fanciness of this vehicle."
The front suspension is what allows the front wheels to move properly over bumps. The drivetrain is what delivers power to the wheels, and together they determine how the front end is built and sealed.
The front suspension controls how the front wheels move and maintain contact with the road, while the drivetrain is the system that sends power to the wheels. On a vehicle like the G-Class, the front suspension/drivetrain layout is described as heavy-duty and older-style, which affects how water and seals behave at the steering knuckle.
four-wheel drive
"I don't believe this vehicle has probably ever been through that kind of thing, as most G-wagens never really leave the road. They have a nice fancy on-road four-wheel drive."
Four-wheel drive means power goes to all four wheels to help with traction. Even if the car is mostly used on-road, water can still get into joints and seals.
Four-wheel drive (4WD) sends engine power to both the front and rear axles for better traction. The episode notes that even though the G-Class has a “nice fancy on-road four-wheel drive,” moisture can still seep into vulnerable areas like the steering knuckle seals.
seal
"There's a big enormous seal. It's a big round ball where the steering knuckle pivots and it's got a very large seal. And if water gets into that seal, then it's all over with."
A seal is like a gasket that keeps grease from leaking and keeps water out. In this case, the seal around the steering knuckle pivot is the barrier—if water gets in, it can cause the problem they’re seeing.
A seal is a rubber or composite barrier that keeps grease and other fluids in place while blocking water and contaminants. Here, the host describes a large round seal at the steering knuckle pivot; if water gets past it, grease can leak and the joint can be compromised.
Byd Seal
"...w or whatever and seep in. There's a big enormous seal. It's a big round ball where the steering knuckle..."
The BYD Seal is an electric car (a battery-powered sedan). The podcast is talking about a part near the steering area and whether it’s sealed well enough to keep water out. If seals fail, moisture can get into places it shouldn’t.
The BYD Seal is an electric sedan designed around battery-electric propulsion and a streamlined, modern body. It comes up in the podcast in a discussion of how parts near the steering area are sealed and how water or moisture can get in if seals aren’t doing their job. The “big round ball” description points to a specific component and the importance of keeping it properly sealed against the elements.
disc brake
"And we're looking at the disc brake here, so this is where the issues are happening. Exactly. Yeah, you're pointing right to where the issue is happening."
A disc brake is the braking system that uses a spinning metal disc and pads to slow the car down. They mention it because it’s near the area they’re inspecting on the front end.
A disc brake uses a rotor (disc) and caliper to slow the vehicle by clamping pads against the rotor. The episode mentions the disc brake area because that’s where they’re pointing to the front-end components associated with the steering knuckle issue.
bearings
"What are those bearings doing? Is that letting the wheel turn from side to side basically? Exactly... And there's shims in there that calibrate so there's not excess flop and play."
Bearings let the wheel/axle rotate smoothly. They also need to be set up precisely—too loose causes wobble and wear, too tight can cause heat and noise.
The bearings inside the knuckle support the axle/wheel assembly and let it rotate smoothly while also handling steering loads. The hosts mention shims used to set bearing preload/clearance so there’s minimal play and no excess looseness.
shims
"And there's shims in there that calibrate so there's not excess flop and play. So it's measured out."
Shims are thin pieces used to get the fit just right. Here they help set how much movement the bearings are allowed to have.
Shims are thin spacers used to fine-tune bearing clearance and alignment. In this job, shims are measured and selected so the bearings don’t have excess play (“flop”) while still rotating correctly.
Toyota Land Cruiser
"...rough rocks with these kind of things and I had a Land Cruiser once and hit a couple of rocks from time to time,..."
The Toyota Land Cruiser is a large SUV designed for driving on rough roads and off-road trails. It’s built to be tough and handle bumps and rocks better than many everyday cars. The podcast brings it up because the speaker has used one in situations where they sometimes hit rocks.
The Toyota Land Cruiser is a full-size, body-on-frame SUV known for serious off-road capability and durability. It’s often discussed in contexts like rough terrain because its drivetrain and chassis are built to handle impacts and uneven surfaces. In the podcast, it’s mentioned as a personal example of a vehicle that could take occasional rock hits during off-road driving.
CV joint
"This is the CV joint, the constant velocity joint on the front drive axle and the boot is torn open and you can see the ball. There's six ball bearings..."
The CV joint is what lets the axle keep driving the wheels even when the suspension moves. If the boot tears, water gets in and the joint can rust and start making noise.
A CV joint (constant velocity joint) is the axle joint that allows power to be transmitted smoothly while the suspension moves and the wheels turn. The segment shows a torn CV boot that lets water and grease mix, leading to rust on the joint’s ball bearings.
boot
"This is the CV joint... and the boot is torn open and you can see the ball."
The boot is the protective cover for the CV joint. If it rips, dirt and water can get in, and that can ruin the joint over time.
The CV boot is the protective rubber cover over the CV joint. When it tears, contaminants like water can enter and mix with grease, accelerating corrosion and joint wear.
genuine Mercedes parts
"Then we put the genuine Mercedes parts in. And would there be any noise associated with it at this level of kind of damage or wear?"
“Genuine Mercedes parts” means Mercedes-made replacement parts. They’re often chosen because they’re designed to fit and work correctly in the original system.
“Genuine Mercedes parts” refers to OEM (original equipment manufacturer) components supplied by Mercedes-Benz for service replacements. The hosts contrast this with cheaper aftermarket sources, implying fit/quality and durability differences.
constant velocity joint
"It is. You can do the same thing with the universal joint but the reason they call it a constant velocity joint is because the speed of the input shaft is the same as the speed of the output shaft"
A CV joint is what connects parts of the drive axle so power can still be sent to the wheels while the suspension moves. It’s designed to keep the wheel-side rotation smooth, even when the angle changes.
A constant velocity (CV) joint is a driveline joint that lets the axle transmit power smoothly even while the suspension moves and the wheels turn. It keeps the input and output shaft rotating at the same speed, which helps prevent vibration and driveline “jerkiness.”
U-joint
"whereas with a U-joint it'll actually change because the U-joint only has two planes of movement"
A U-joint is a connector that lets the drive shaft bend as the wheels move. It doesn’t keep things rotating at exactly the same speed the way a CV joint does, so it can feel less smooth.
A U-joint (universal joint) is another type of driveline joint that allows angular movement. Unlike a CV joint, a U-joint does not keep input and output shaft speeds identical, so it can cause speed variation and more vibration under load.
pivot on the knuckle
"these bearings are basically for that pivot on the knuckle... one bearing sits on top, one bearing sits on the bottom"
The knuckle is part of the front suspension/steering that the wheel assembly connects to. Bearings there help the moving parts pivot smoothly; if they’re contaminated or worn, the front end can feel off.
The knuckle is the steering/suspension component that the axle and wheel hub interface with. Bearings at the knuckle support the pivoting motion, so if they’re worn or contaminated, steering feel and alignment can be affected.
OEM Mercedes grease
"We use the OEM Mercedes grease in here. It's an interesting kind of light color almost looks like Vaseline but it's not."
OEM grease is the specific grease the manufacturer recommends for that part. Using the wrong grease can cause the joint not to be protected properly over time.
OEM (Original Equipment Manufacturer) grease is the lubricant specified by the vehicle maker for that joint or bearing. Using the correct grease matters because the wrong product may not have the right properties for sealing, lubrication, and long-term compatibility with the materials.
knuckle assembly
"So this is basically repacked the knuckle assembly. This kind of rounded piece here and you can make out there's another one up top. That's where these would sit so that lets the wheel turn left and right"
The knuckle assembly is a key front steering/suspension piece that lets the wheel turn. Repacking it with the right grease helps keep the moving parts lubricated and protected from water.
A steering knuckle assembly is the part of the front suspension/steering that the wheel hub and bearings mount to, allowing the wheel to pivot left and right. Repacking it with the correct grease helps keep the bearings lubricated and the internal seal intact, which prevents water intrusion and accelerated wear.
repacked
"So this is basically repacked the knuckle assembly... You should pack it with grease because when you pack it with grease it forces any moisture out and it keeps the ball lubricated so it keeps the seal in good shape"
“Repacked” here means they clean out the old grease and put in fresh grease. That helps keep water out and keeps the moving parts lubricated.
“Repacked” means removing the old lubricant and refilling the joint/knuckle area with fresh grease. In sealed steering joints, repacking is important because it can help purge moisture and maintain lubrication so the seal stays in good condition.
rusted
"It's smart to fix this beforehand because if you leave it too long that ball can get rusted and if it gets rusted then it definitely won't seal well"
Rusted means the metal has started corroding due to moisture. If that happens inside the steering joint, it can stop the seal from working well and make the parts wear out faster.
Rust is corrosion that forms when moisture reacts with metal surfaces. In a sealed steering knuckle, rusting can prevent the seal from sealing properly and can also contribute to bearing wear and looseness, which then drives up repair cost.
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