The 2009 Mercedes-Benz Trucks GL450 blends full-size SUV utility with the road manners and upscale character buyers expected from a Mercedes-Benz luxury truck of its era. It sits in a period when wheel and tire packages became a much bigger part of both appearance and on-road feel. For this exact GL450, tire fitment centers on three radial sizes: 265/60R18, 275/55R19, and 275/50R20, with the correct choice tied to the wheel package and sub-model. That makes this less about vintage construction choices and more about confirming rim diameter, preserving the intended stance, and selecting the right tire for everyday use or careful replacement.
Which Tire Size Is Right for The 2009 Mercedes-Benz Trucks GL450
The 2009 Mercedes-Benz Trucks GL450 uses three primary tire sizes, and the right one depends on the specific sub-model and wheel diameter. All three are metric radial sizes, but they are matched to different 18-inch, 19-inch, or 20-inch rims, so confirming the wheel on the vehicle is the first step before comparing tire options.
A 265/60R18 tire uses a 265-millimeter section width, a 60-series aspect ratio, radial construction, and an 18-inch rim diameter. On the 2009 Mercedes-Benz Trucks GL450, this is one of the primary radial fitments and is tied to an 18-inch wheel package rather than every GL450 configuration. The sizing gives buyers a modern metric format that is familiar and easy to compare when replacing worn tires. This size should be chosen only after confirming that the vehicle actually carries 18-inch wheels and has not been changed to a different factory or aftermarket setup.
A 275/55R19 tire indicates a 275-millimeter section width, a 55-series profile, radial construction, and fitment on a 19-inch rim. For the 2009 Mercedes-Benz Trucks GL450, it is a primary fitment used on certain configurations and should be treated as a wheel-specific size rather than a universal GL450 replacement. Compared with other applicable sizes, the key difference here is the 19-inch rim requirement. This is the size to evaluate when the truck retains its 19-inch wheel package and the goal is to stay with the intended fitment range for that setup.
A 275/50R20 tire combines a 275-millimeter section width with a 50-series profile, radial construction, and a 20-inch rim diameter. On the 2009 Mercedes-Benz Trucks GL450, this size is associated with the w/Appearance Pkg. sub-model, making it a package-specific fitment rather than a size shared across the whole model line. Its lower-profile metric format reflects a larger-wheel presentation while staying within the GL450's primary fitment family. Buyers considering this size should verify that the vehicle has the correct 20-inch wheels and enough clearance for the exact tire chosen, especially if any suspension or wheel changes have been made.
Sub-model fitment matters on the 2009 Mercedes-Benz Trucks GL450 because the tire size changes with the wheel package. The first step is identifying whether the truck is the Base model or the w/Appearance Pkg. version, then matching the tire to the correct rim diameter.
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2009 Mercedes-Benz Trucks GL450 Base
The 2009 Mercedes-Benz Trucks GL450 Base uses either 265/60R18 or 275/55R19 radial tires, depending on the wheel setup on the vehicle. That means replacement starts with confirming whether the truck has 18-inch or 19-inch rims before comparing tire choices.
The 2009 Mercedes-Benz Trucks GL450 w/Appearance Pkg. uses the 275/50R20 radial size. Tire selection for this version centers on maintaining the correct 20-inch fitment and checking the actual wheel and suspension setup if the truck has been modified since new.
The tire sizes listed on this page assume factory-standard vehicle configuration. The following modifications may affect tire fitment and are not reflected in this guide:
Suspension changes (lowering, lift kits, spring replacements)
Body alterations (fender modifications, custom bodywork)
If your vehicle has been modified from factory specifications, verify tire clearance before purchase.
Frequently Asked Questions
These FAQs focus on the exact tire sizes used on the 2009 Mercedes-Benz Trucks GL450, how they relate to each sub-model, and what to verify before replacing tires on an 18-inch, 19-inch, or 20-inch wheel package.
Tire Size & Fitment
What tire size fits a 2009 Mercedes-Benz Trucks GL450?
The 2009 Mercedes-Benz Trucks GL450 uses three primary tire sizes: 265/60R18, 275/55R19, and 275/50R20. The Base model uses either 265/60R18 or 275/55R19, while the GL450 w/Appearance Pkg. uses 275/50R20.
The right choice depends on the actual wheel package on the truck, not just the model name on the tailgate. Checking the current rim diameter is essential, because an 18-inch, 19-inch, or 20-inch tire must match the same wheel diameter to be usable.
What size rim does a 2009 Mercedes-Benz Trucks GL450 use?
A 2009 Mercedes-Benz Trucks GL450 can use 18-inch, 19-inch, or 20-inch rims, depending on the sub-model and wheel package. The matching tire sizes are 265/60R18 for 18-inch rims, 275/55R19 for 19-inch rims, and 275/50R20 for 20-inch rims.
Rim diameter is the first fitment point to confirm before buying replacement tires. It is also wise to verify the actual wheel currently on the vehicle, since many SUVs of this era have seen wheel swaps that can change the correct tire size from the original package.
Why does the 2009 Mercedes-Benz Trucks GL450 have more than one tire size?
The 2009 Mercedes-Benz Trucks GL450 has more than one tire size because different sub-models and wheel packages used different rim diameters. The Base model could carry either 18-inch or 19-inch fitments, while the w/Appearance Pkg. version used a 20-inch setup.
That means tire selection is tied directly to the wheel package on the vehicle. A buyer should confirm the sub-model and physically check the wheel diameter before choosing tires, since the three sizes are close in overall profile but are built for different rim sizes.
Choosing the Right Tire
What should I consider when choosing a 2009 Mercedes-Benz Trucks GL450 tire?
Start with the correct primary size for the truck: 265/60R18, 275/55R19, or 275/50R20. On a 2009 Mercedes-Benz Trucks GL450, the key decision is not bias-ply versus radial, since all primary fitments are radial, but matching the tire to the correct wheel package.
After the size is confirmed, compare how the truck is used and whether it still has its original wheels and suspension height. Daily driving, occasional towing demands, and any aftermarket wheel changes can all affect which replacement tire makes the most practical sense within the correct size.
How do I choose between the available 265/60R18, 275/55R19, and 275/50R20 tires for a 2009 Mercedes-Benz Trucks GL450?
These three sizes are not interchangeable choices for the same wheel. Each one belongs to a specific rim diameter and GL450 configuration, so the correct approach is to match the tire size to the wheel already on the vehicle.
Once that is settled, compare tire options within the correct size rather than jumping between sizes. The useful checks are wheel diameter, overall vehicle setup, intended road use, and whether the truck has stayed stock or has been altered with different wheels, springs, or suspension components.
What rim-fitment details matter when choosing tires for a 2009 Mercedes-Benz Trucks GL450?
The most important rim-fitment detail is diameter, because the 2009 Mercedes-Benz Trucks GL450 uses three different wheel sizes across its fitments: 18, 19, and 20 inches. A 265/60R18 belongs on an 18-inch rim, a 275/55R19 on a 19-inch rim, and a 275/50R20 on a 20-inch rim.
Width and overall wheel setup matter too, especially if the SUV no longer has its original wheels. Checking the actual wheel dimensions and looking for clearance at the fenders and suspension helps prevent a mismatch when replacing tires on a modified or previously updated vehicle.
Restoration & Appearance
Does correct tire fitment matter for a 2009 Mercedes-Benz Trucks GL450 restoration or preservation project?
Yes, correct tire fitment still matters on a 2009 Mercedes-Benz Trucks GL450 even though it is a modern radial-fitment vehicle rather than a classic bias-ply application. Keeping the proper size with the proper wheel diameter helps preserve the truck’s intended stance, proportions, and overall presentation.
A preservation-minded owner should start by confirming whether the truck is a Base model on 18-inch or 19-inch wheels or a w/Appearance Pkg. model on 20-inch wheels. If originality is a concern, compare the current wheel-and-tire setup with vehicle records and known factory equipment before making a change.
Which tire size suits the original appearance of a 2009 Mercedes-Benz Trucks GL450?
The size that suits the original appearance of a 2009 Mercedes-Benz Trucks GL450 is the size that matches its correct wheel package: 265/60R18, 275/55R19, or 275/50R20. The truck’s visual balance depends on keeping the wheel and tire combination aligned with the sub-model it carries.
Moving away from the proper fitment can change the way the GL450 sits and how much sidewall shows around the wheel. Owners who want to preserve a stock-looking presentation should verify the truck’s sub-model, wheel diameter, and current setup before replacing tires with a different size.
Fitment, Maintenance & Road Use
Can modifications affect tire fitment on a 2009 Mercedes-Benz Trucks GL450?
Yes, modifications can affect tire fitment on a 2009 Mercedes-Benz Trucks GL450. Aftermarket wheels, suspension changes, lowering, or altered ride height can all change how a 265/60R18, 275/55R19, or 275/50R20 tire sits within the wheelwell and around steering and suspension components.
A truck that has been changed from its original setup should be checked more carefully before ordering replacement tires. The main points are actual wheel diameter, wheel width, turning clearance, and space at the fenders and suspension, especially near full lock and full compression.
What should I inspect before driving a 2009 Mercedes-Benz Trucks GL450 on new tires?
Before driving a 2009 Mercedes-Benz Trucks GL450 on new tires, inspect the wheels for damage, confirm that the tire size matches the rim diameter, and make sure each tire is inflated properly for the application. It is also smart to look over the valve stems and check for any obvious clearance concerns.
A short, careful road test helps confirm that the tires track properly and do not rub during turns or over bumps. The same inspection should include suspension condition, uneven wear signs from the previous tires, and any vibration that could point to wheel or alignment issues.
What should I check before a longer drive in a 2009 Mercedes-Benz Trucks GL450?
Before a longer drive, check tire pressure, tread condition, and the sidewalls on the 2009 Mercedes-Benz Trucks GL450 for cracking, bulges, cuts, or signs of air loss. It is also worth confirming that the truck is wearing the correct size for its wheel package and that no tire is rubbing.
Longer trips put more heat and load into the tires, so condition matters as much as size. A vehicle that has spent long periods parked should get extra attention, since age, storage conditions, and underinflation can affect tire health even when tread depth still looks acceptable.
