Fuel Tanks

Frequently Asked Questions About Semi-Truck Fuel Tanks

What size fuel tank do I need for my truck, and how do I determine the right capacity?

Fuel tank capacity depends on your typical routes and truck specifications. Most long-haul drivers prefer 100-150 gallon tanks per side for extended range, while regional drivers often choose 50-80 gallon tanks. To determine the right size, measure your existing tank mounting area (length x height x depth) and check your frame rail spacing. Remember that larger tanks add weight, which affects payload capacity. Consider dual tank setups for better weight distribution and increased range without sacrificing ground clearance.

Will aftermarket fuel tanks fit my specific truck model and year?

Fuel tank compatibility varies by manufacturer and model year. Most aftermarket tanks are designed to fit standard frame rail widths of 34-35 inches for Freightliner, Peterbilt, Kenworth, and Volvo trucks from 1990 onwards. However, some models like the Freightliner Cascadia (2008-2017) may require specific brackets or modifications. Always verify your frame rail measurements, step box configuration, and exhaust routing before ordering. Check if your truck has aftertreatment devices that might interfere with tank placement.

What's the difference between aluminum and steel fuel tanks, and which should I choose?

Aluminum tanks are 50-60% lighter than steel, improving fuel economy and payload capacity.  Aluminum fuel tanks are also lightweight and naturally resistant to rust, making them a common choice for semi trucks. Steel tanks are more affordable and highly durable against impacts but require regular maintenance to prevent rust. Aluminum is ideal for weight-conscious operations and coastal regions with salt exposure. Steel works well for heavy-duty applications where impact resistance matters more than weight. Both materials typically last 10-15 years with proper care. When choosing between materials, consider the tank's weight, corrosion resistance, dimensions, and compatibility with your truck rather than material alone.

Can I install a replacement fuel tank myself, or do I need professional installation?

While experienced mechanics can install fuel tanks themselves, professional installation is recommended for safety and warranty reasons. Installation requires draining existing fuel, removing old tanks, transferring or replacing sending units, mounting new brackets, and ensuring proper fuel line connections. You'll need a tank jack, proper lifting equipment, and knowledge of fuel system safety. Many installations take 3-4 hours per tank. Improper installation can cause leaks, gauge malfunctions, or tank damage not covered under warranty.

Do aftermarket fuel tanks come with sending units and mounting hardware?

Most aftermarket fuel tanks are sold as tank-only units without sending units, straps, or brackets. You'll typically need to transfer your existing sending unit or purchase one separately that matches your truck's gauge system (240-33 ohm for most trucks). Basic mounting straps are sometimes included, but specialized brackets for specific truck models are usually sold separately. Budget an additional $150-300 for sending units and mounting hardware if starting fresh. Always verify what's included before ordering to avoid installation delays.

Do I need a new fuel tank cap or mounting bracket when I upgrade to a bigger tank?

Often, yes. A larger tank typically needs a larger fuel tank bracket to stay secure, and it's a good time to check whether your fuel tank cap still seals properly on the new tank's fill neck.

Should I run a single fuel tank or dual tanks?

Dual tanks split weight across both sides of the chassis, which helps with ground clearance and range on long-haul routes, while a single tank is simpler to install and maintain. Before deciding, check our fuel tank measurement guide to confirm what will actually fit your frame rails.