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                                 UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
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SEC 1913 (02-02)

                                       


                                 [WABASH NATIONAL LOGO]

                            LETTER FROM THE PRESIDENT

As we begin 2005, our focus at Wabash National Corporation is changing:

               "IT'S NOT A TURN-AROUND ANYMORE. IT'S ABOUT THE FUTURE."

Over the last few years, every associate at Wabash has worked diligently,
effectively and successfully to overcome the many critical challenges that
threatened our Company. Their efforts have transformed the Company. In 2005, we
will mark our twentieth anniversary - a new era has begun and we are focused on
the future. In addition to the continuous improvement mindset and lean
manufacturing initiatives that we have deployed over the last few years, we will
continue to nurture and refine the traits Wabash National was founded on:
product and technological leadership, innovation and a focus on the success of
our customers. Our vision for 2005 is to merge these attributes with initiatives
to create and enhance long term shareholder value.

2004:

Results in 2004 improved significantly over our 2003 results. We achieved sales
of $1.0 billion and net income of $58.4 million versus sales of $887.9 million
and a loss of $57.2 million in 2003. Despite unprecedented increases in raw
material costs in 2004, the Company's gross margin grew to 12.1% versus 5.9% in
2003. The 2003 period included a $28.5 million charge related to a loss on asset
impairment. As of December 31, 2004, we had $42 million in cash and no bank
debt, achieving the goal established in 2002 to be bank debt free.

      SALES:

      -     Grew unit volume by over 10,000 trailers year-over-year.

      -     Increased van market share by over 1% despite a significant
            year-over-year reduction in unit volume from core accounts; none of
            which were lost.

      -     Added approximately 225 new, primarily mid-market accounts that
            purchased approximately 6,000 new trailers, the majority of which
            were our proprietary DuraPlate(R) product. Our success in the
            mid-market far exceeded our original expectations.

      -     Recovered approximately 90% of our raw material cost increases
            through increased selling prices.

        P.O. Box 6129 - Lafayette, Indiana 47903 - Phone: (765) 771-5300


      OPERATIONS:

      -     Continued our organizational focus on safety with a 41% improvement
            in Total Recordable Incident Rate. We are now 50% better than the
            industry norm.

      -     Improved First Pass Yield across all production lines from 20% in
            2002 to 95% in 2004. This accomplishment allowed the Company to
            significantly reduce warranty reserves and expenses in 2004.

      -     Awarded the prestigious 2003 U.S. Senate Productivity Award from the
            State of Indiana for the significant cost savings and productivity
            we achieved in the prior two years.

      RETAIL/BRANCH OPERATIONS:

      -     Improved operating results $13 million year-over-year.

      -     Achieved record new trailer sales with 40% fewer branch locations.

2005 OUTLOOK:

Moving forward we see our industry cycle in the formative stage, as 2004 was the
first year in the last four when marginal replacement of the industry's aging
trailer fleet occurred. Our customers, the major truckload and
less-than-truckload fleets, have seen vast improvements in their respective
operations, and as such, vast improvements in their balance sheets. All this
seemingly signifies a sustainable recovery in the transportation industry upon
which we intend to capitalize.

      MID-MARKET GROWTH:

            This defined market segment of 1,250 carriers with trailer fleet
            sizes between 500 and 7,500 units has in excess of 1 million
            trailers in service and an approximate yearly replacement level of
            100,000 units. Today, our share of this market is less than 10%.
            Over the next three years, we intend to capture approximately 30% -
            35% representing an estimated 20,000 additional units. If
            successful, this new business would represent $450 to $500 million
            in sales. With focus, determination, quality trailer products, and a
            commitment to ensuring our customers' success, we believe the
            probability of attaining this goal is high.

      LOWER COST MANUFACTURING:

            Over the last several years, we have made exceptional improvements
            in our trailer assembly process as measured in terms of
            productivity, quality, safety and reduced costs. We strive to
            continuously improve processes and further reduce costs. In 2005, we
            begin a three-year, $40 million program to replace four trailer
            assembly lines. The schedule is to replace one line in 2005, two in
            2006 and one in 2007. Each line is estimated to cost $10 million and
            each will produce an estimated annual cost savings of $7 million.
            This investment in our production capabilities will help to
            revolutionize trailer manufacturing, incorporating the use of
            technology proven in the automotive industry.



      NEW ERP SYSTEM:

            Our next step in improving build processes is implementation of an
            Enterprise Resource Planning (ERP) system. This system, which will
            be implemented in stages over the course of twenty-four months, will
            integrate departments and functions across the Company, enhance our
            ability to service our customers, and improve our control
            environment. We recognize that the success of this type of system
            implementation is widely dependent upon senior executive support
            and, therefore, my direct reports and I will champion this project
            through its completion.

      BENCH STRENGTH:

            Selecting and developing future managers is a crucial task. We have
            begun to evaluate and measure critical leadership positions within
            the Company to ensure that as the Company grows and its strategy
            evolves, our initiatives are being actively managed and management
            can deliver sustainable business results.

      RAW MATERIAL/COMPONENT COST REDUCTION:

            Raw materials and components represent approximately 75% of our
            product cost and present a tremendous opportunity for significant
            cost reductions. We believe that standardization of parts and
            processes will enable us to obtain more competitive pricing and
            achieve improved assembly efficiencies. We are also working closely
            with suppliers to target and obtain greater cost and productivity
            sharing. We are targeting over 300 basis point annual improvement
            over the next three years.

This letter outlines just a few of the major undertakings in 2005, and
subsequent years, to improve profitability, enhance shareholder value, and
address the needs of our customers. Given continuing, favorable economic and
geopolitical conditions, we expect the positive market cycle to extend through
2008. We fully intend to take advantage of this prolonged period of prosperity
with record sales and profitability.

To the associates of Wabash National Corporation, I state,

               "WE HAVE EARNED THIS RIGHT. IT IS NOW ABOUT THE FUTURE."

/s/ William P. Greubel
----------------------
William P. Greubel
President & CEO

[WABASH NATIONAL LOGO]

                             STOCKHOLDER INFORMATION



                                                                    
EXECUTIVE OFFICERS                                                     DIRECTORS                                             
William P. Greubel                                                     David C. Burdakin                                     
President, Chief Executive Officer and Director                        President                                             
                                                                       HON Company                                           
Richard J. Giromini                                                                                                          
Executive Vice President - Chief Operating Officer                     William P. Greubel                                    
                                                                       President and Chief Executive Officer                 
Rodney P. Ehrlich                                                      Wabash National Corporation                           
Senior Vice President - Chief Technology Officer                                                                             
                                                                       John T. Hackett                                       
Brent A. Larson                                                        Chairman of the Board of Directors                    
Senior Vice President - Sales and Marketing                            Wabash National Corporation                           
                                                                                                                             
Jerry R. Linzey                                                        Dr. Martin C. Jischke                                 
Senior Vice President - Manufacturing                                  President                                             
                                                                       Purdue University                                     
Timothy J. Monahan                                                                                                           
Senior Vice President - Human Resources                                Stephanie K. Kushner                                  
                                                                       Vice President and Chief Financial Officer            
Robert J. Smith                                                        Federal Signal Corporation                            
Senior Vice President - Chief Financial Officer                                                                              
                                                                       Larry J. Magee                                        
AUDITORS                                                               Chairman, CEO and President                           
Ernst & Young                                                          BFS Retail & Commercial Operations, LLC               
111 Monument Circle                                                                                                          
Suite 2600                                                             Scott K. Sorensen                                     
Indianapolis, Indiana  46204-5120                                      Vice President and Chief Financial Officer            
                                                                       Hillenbrand Industries, Inc.                          
TRANSFER AGENT                                                                                                               
National City Bank                                                     Ronald L. Stewart                                     
Corporate Trust Operations                                             President and Chief Executive Officer                 
PO Box 92301                                                           Material Sciences Corporation                         
Cleveland, Ohio  44193-0900                                                                                                  
(800) 622-6757                                                         STOCK LISTING                                         
                                                                       Symbol:  WNC                                          
REQUESTS                                                               New York Stock Exchange                               
For stockholder requests for information or assistance,                As required by the NYSE rules, in 2004, the CEO       
Please write or telephone:                                             certified to the NYSE that he was not aware of any    
       Wabash National Corporation                                     violation by the Corporation of NYSE corporate        
       c/o Investor Relations                                          governance listing standards as of the date of that   
       PO Box 6129                                                     certification,                                        
       Lafayette, Indiana  47903-6129                                                                                        
       (765) 771-5310                                                  FORM 10-K                                             
                                                                       In lieu of a separate annual report to stockholders,  
INTERNET ADDRESS                                                       enclosed is Wabash National Corporation's Form        
http://www.wabashnational.com                                          10-K, which included as an exhibit the certifications 
                                                                       required by Section 302 of the Sarbanes Oxley Act.    



[WABASH NATIONAL CORPORATION LOGO]