Kenworth W990 Fuel Tanks

Frequently Asked Questions About Kenworth W990 Fuel Tanks

What size fuel tanks are available for the Kenworth W990, and how do I determine which fits my truck?

Kenworth W990 fuel tanks typically come in 100, 120, and 150-gallon capacities. To determine the right size, check your truck's spec sheet or measure your existing tank's dimensions. The W990 accepts standard 23-inch or 25-inch diameter tanks. Keep in mind that larger tanks may require bracket adjustments and could affect your truck's weight distribution. Most 2019-2024 W990 models can accommodate any of these sizes, but always verify your specific frame rail spacing before ordering.

Are these fuel tanks made of aluminum or steel, and which material is better for my application?

Most aftermarket W990 fuel tanks are made from either polished aluminum or powder-coated steel. Aluminum tanks are lighter (saving approximately 50-70 pounds per tank), resist corrosion better, and maintain their appearance with minimal maintenance. Steel tanks are more impact-resistant and typically cost 20-30% less. For long-haul applications where weight matters, aluminum is preferred. For severe-duty or construction applications where durability is paramount, steel may be the better choice.

What's involved in installing replacement fuel tanks on a W990, and can I do it myself?

Installation typically takes 3-4 hours per tank and requires basic mechanical skills. You'll need to drain the existing tank, disconnect fuel lines and sending unit wiring, remove the mounting straps, and carefully lower the old tank. New installations require transferring the sending unit, fuel pickup, and vents to the new tank. Critical steps include properly torquing the mounting straps (typically 45-55 ft-lbs) and ensuring all connections are leak-free. While DIY installation is possible, many owners prefer professional installation to ensure proper fuel system connections and avoid warranty issues.

Will aftermarket fuel tanks affect my fuel gauge accuracy or require recalibration?

Most quality aftermarket tanks are designed to work with your existing W990 sending unit and gauge without recalibration. However, you must ensure you're transferring your original sending unit properly and that it's compatible with the new tank's depth. Some customers report slight gauge inaccuracies when switching between significantly different tank sizes (like going from 100 to 150 gallons). In these cases, a sending unit adjustment or replacement may be necessary to maintain accurate fuel level readings.

What's the difference between round and D-shaped fuel tanks for the W990?

Round tanks are the traditional choice, offering maximum capacity and easier manufacturing that typically results in lower costs. D-shaped (or rectangular) tanks sit closer to the frame rails, providing better ground clearance and a cleaner appearance that many W990 owners prefer. D-shaped tanks may offer 5-10% less capacity than round tanks of similar dimensions but provide better protection from road debris and easier access to components behind the tank. Your choice often depends on whether you prioritize maximum fuel capacity or aesthetics and ground clearance.