The United States Postal Service Long Life Vehicle may finally be reaching the end of its road.

The search to replace the iconic but outdated Grumman LLV truck, which went out of production in 1994, began four years ago and has entered its final stage, with road tests of the competing vehicles now complete.

According to Trucks.com, U.S. Postmaster General Megan Brennan told a congressional committee last week that a final decision is expected by fall, about a year behind the program’s original schedule. The contract calls for 180,000 trucks to be delivered over five to seven years at a price between $25,000 and $35,000 each, which means it could be worth as much as $6.3 billion to the winner.

The basic parameters for the vehicle laid out in the original request for information called for a right-hand-drive van with an aluminum or composite body, sliding curbside doors for both the passenger compartment and cargo area, a payload capacity of 1,500 pounds, ceiling height of 6 feet, 4 inches, an overall length of 19 feet and an all-wheel-drive option. A specific type of powertrain was not specified, but the cost of operation is part of the assessment.

Five vehicles are in the running, at least three of which are collaborations. Details largely remain confidential, but they have been spotted making the rounds, so here's a look at what may be pulling up in front of your home soon.

AM GENERAL

The South Bend, Ind., company behind the Humvee has a long relationship with the federal government and the production capability to get the job done. Its straightforward-looking proposal features Volvo interior components suggesting a potential tie-up with the Chinese-owned brand.

VT HACKNEY/WORKHORSE

Commercial truck specialist VT Hackney has teamed up with electric vehicle outfit Workhorse on a battery-powered prototype that could potentially spawn a plug-in hybrid using technology Workhorse has been developing for a pickup.

MAHINDRA

Indian automaker Mahindra last year opened a manufacturing facility in Michigan to build a small off-roader and would need to expand its operations in the United States to meet the contract's domestic manufacturing requirements if its truck is chosen.

KARSAN/MORGAN OLSON

Turkey's Karsan previously tried and failed to win the contract to build New York City's Taxi of Tomorrow, but may have an inside line on the mail truck. Its American partner in the endeavor, Morgan Olson, is a corporate descendant of Grumman.

OSHKOSH/FORD

Oshkosh and Ford are working together on the only production-based model in the final five. Based on a high-roof Ford Transit van, which can be had with a diesel engine and will be available with all-wheel-drive starting next year, the entry has been modified with the required sliding doors and plenty of protective body cladding.

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