The fuel storage tank of the Catera is made of high-density polyethylene and is located behind the rear wheels. It is held in place by two metal straps attached to the under body of the vehicle. The tank shape includes a sump to maintain a constant supply of fuel around the fuel pump strainer during low fuel conditions or aggressive maneuvers.
The tank also contains a fuel vapor vent valve with rollover protection. This vent valve also features a two phase vent calibration which increases fuel vapor flow to the canister when operating temperatures increase the tank pressure beyond an established threshold.
The Seville, Deville, and Eldorado carries the same type tank but it is located in front of the rear wheels.