Exhibit 99.1

NAVISTAR REPORTS FOURTH QUARTER RESULTS

LISLE, Ill. — December 16, 2014 — Navistar International Corporation (NYSE: NAV) today announced a fourth quarter 2014 net loss of $72 million, or $0.88 per diluted share, compared to a fourth quarter 2013 net loss of $154 million, or $1.91 per diluted share. Revenues in the quarter were $3.0 billion, up $257 million or 9.3 percent, versus the fourth quarter of 2013.

“Our fourth quarter results—and the results for the entire fiscal year—reflect our continued progress improving business operations across the enterprise and positive trends in the North American industry,” said Troy A. Clarke, Navistar president and chief executive officer. “In 2014, we increased our production, chargeouts and order backlog; continued to reduce warranty spend; and achieved structural cost savings that further lowered our breakeven point.”

Fourth quarter 2014 EBITDA was $66 million versus an EBITDA loss of $227 million in the same period one year ago. This year’s fourth quarter included $60 million of restructuring, impairments and other charges partially offset by a $10 million favorable adjustment in pre-existing warranty. As a result, adjusted fourth quarter 2014 EBITDA was $116 million, which was within the company’s fourth quarter guidance.

Navistar finished the fourth quarter 2014 with $1 billion in manufacturing cash, cash equivalents and marketable securities, which included a $91 million increase in an intercompany loan from Navistar Financial Corporation (NFC), Navistar’s captive finance company, to support used-truck activities.

The company reduced its year-over-year structural costs in the fourth quarter by an additional $66 million, including $48 million in savings from selling, general, and administrative (SG&A) expense and $18 million in reduced engineering costs. Navistar reduced structural costs by $311 million for the year, which exceeded the company’s full year target of $300 million.

Navistar’s warranty spend improved in the fourth quarter, down 22 percent year-over-year. These results were driven by quality performance improvements, lower repair costs and a reduced population of legacy engines still in the warranty periods.

Other fourth quarter highlights included a 23 percent year-over-year increase in chargeouts for Class 6-8 trucks and buses in the United States and Canada. Chargeouts for Class 6-8 trucks were up 12 percent for fiscal year 2014, which included a 21 percent increase in Class 8 heavy trucks compared to 2013. In addition, end-of-year order backlog for Class 6-8 trucks was up 24 percent year-over-year.

The net loss for fiscal year 2014 was $619 million, or $7.60 per diluted share, versus a net loss of $898 million, or $11.17 per diluted share, for fiscal year 2013. Fiscal year 2014 adjusted EBITDA was $294 million versus $89 million adjusted EBITDA for 2013. Revenue for fiscal year 2014 was flat at $10.8 billion compared to fiscal year 2013.

“We continue to make the necessary changes to improve the company and we’re entering 2015 in a much stronger position than we were one year ago,” Clarke added. “We’ve restructured our core North American business, have the right products in place, and established the right leadership team. We are well-positioned to meet our 8-10 percent EBITDA margin run rate target exiting 2015.”

The company provided the following guidance:

Navistar will host an Analyst Day February 4 at the company’s headquarters in Lisle, Ill., to share details and plans for fiscal year 2015 and beyond.

Summary of Financial Results:

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North America Truck — For the fourth quarter 2014, the North America Truck segment recorded a loss of $55 million, compared with a year-ago fourth quarter loss of $355 million. The year-over-year improvement was primarily driven by higher traditional truck volumes, declining warranty expense and structural costs, as well as the non-repeat of certain impairment charges. Chargeouts for traditional markets were up year-over year in the fourth quarter by 23 percent, reflecting a 14 percent increase of Class 8 trucks and a 41 percent increase in Class 6/7 trucks.

Navistar recently announced its plans to close its block and head foundry operations in Indianapolis, resulting in an $11 million charge in the quarter for employee separation benefits, pension and other postretirement contractual termination benefits, inventory reserves and other related costs. As a result, the company expects to reduce operating costs by about $13 million annually.

For the fiscal year 2014, the North America truck segment recorded a loss of $408 million, compared with a fiscal year 2013 loss of $902 million, primarily driven by lower charges for adjustments to pre-existing warranties of $52 million versus $404 million in fiscal year 2013.

North America Parts — For the fourth quarter 2014, the North America Parts segment recorded a profit of $143 million, compared to a year-ago fourth quarter profit of $147 million. The decrease was primarily due to a decline in military and Blue Diamond Parts sales, partially offset by improvements in our commercial markets.

For the fiscal year 2014, the North America Parts segment recorded a profit of $500 million, compared to a fiscal year 2013 profit of $476 million, primarily driven by record sales and lower operating costs in our North American commercial markets.

Global Operations — For the fourth quarter 2014, the Global Operations segment recorded a loss of $33 million compared to a year-ago fourth quarter loss of $6 million. The year-over-year decline was primarily driven by a decline in South American engine volumes as well as charges related to right-sizing actions for the Brazilian truck business.

For the fiscal year 2014, the Global Operations segment recorded a loss of $218 million compared to a year-ago fiscal year loss of $6 million, primarily driven by $178 million of asset impairment charges and the fourth quarter charges recognized by the Brazilian truck business. In addition, the continued economic downturn in the Brazil economy has contributed to lower engine volumes of 22 percent in 2014. Partially offsetting these factors were improvements in the export truck operations.

Financial Services — For the fourth quarter 2014, the Financial Services segment recorded a profit of $26 million compared to fourth quarter 2013 profit of $17 million. The increase was driven by the interest earned on an intercompany loan and an increase in the net financial margin from higher average finance receivables balances during the quarter.

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For the fiscal year 2014, the Financial Services segment recorded a profit of $97 million, compared to a fiscal year 2013 profit of $81 million, primarily driven by higher interest income from intercompany loans and lower structural costs, which more than offset the effects of lower overall retail balances and an increase in the provision for loan losses in Mexico.

About Navistar

Navistar International Corporation (NYSE: NAV) is a holding company whose subsidiaries and affiliates produce International^® brand commercial and military trucks, MaxxForce^® brand diesel engines, and IC Bus™ brand school and commercial buses. An affiliate also provides truck and diesel engine service parts. Another affiliate offers financing services. The International^® ProStar^® with Cummins ISX15 and International^® TerraStar^® 4x4 were named 2014 heavy-duty and medium-duty commercial truck of the year, respectively, by the American Truck Dealers (ATD) association. Additional information is available at www.Navistar.com.

Forward-Looking Statement

Information provided and statements contained in this report that are not purely historical are forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, Section 21E of the Securities Exchange Act of 1934, as amended, and the Private Securities Litigation Reform Act of 1995. Such forward-looking statements only speak as of the date of this report and the company assumes no obligation to update the information included in this report. Such forward-looking statements include information concerning our possible or assumed future results of operations, including descriptions of our business strategy. These statements often include words such as “believe,” “expect,” “anticipate,” “intend,” “plan,” “estimate,” or similar expressions. These statements are not guarantees of performance or results and they involve risks, uncertainties, and assumptions. For a further description of these factors, see the risk factors set forth in our filings with the Securities and Exchange Commission, including our annual report on Form 10-K for the fiscal year ended October 31, 2014. Although we believe that these forward-looking statements are based on reasonable assumptions, there are many factors that could affect our actual financial results or results of operations and could cause actual results to differ materially from those in the forward-looking statements. All future written and oral forward-looking statements by us or persons acting on our behalf are expressly qualified in their entirety by the cautionary statements contained or referred to above. Except for our ongoing obligations to disclose material information as required by the federal securities laws, we do not have any obligations or intention to release publicly any revisions to any forward-looking statements to reflect events or circumstances in the future or to reflect the occurrence of unanticipated events.

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Navistar International Corporation and Subsidiaries

Consolidated Statements of Operations

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Navistar International Corporation and Subsidiaries

Consolidated Balance Sheets

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Navistar International Corporation and Subsidiaries

Condensed Consolidated Statements of Cash Flows

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Navistar International Corporation and Subsidiaries

Segment Reporting

(Unaudited)

We define segment profit (loss) as net income (loss) from continuing operations attributable to Navistar International Corporation excluding income tax benefit (expense). The following tables present selected financial information for our reporting segments:

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SEC Regulation G Non-GAAP Reconciliation

The financial measures presented below are unaudited and not in accordance with, or an alternative for, financial measures presented in accordance with U.S. generally accepted accounting principles (“GAAP”). The non-GAAP financial information presented herein should be considered supplemental to, and not as a substitute for, or superior to, financial measures calculated in accordance with GAAP and are reconciled to the most appropriate GAAP number below.

Earnings (loss) Before Interest, Income Taxes, Depreciation, and Amortization (“EBITDA”):

We define EBITDA as our consolidated net income (loss) from continuing operations attributable to Navistar International Corporation, net of tax, plus manufacturing interest expense, income taxes, and depreciation and amortization. We believe EBITDA provides meaningful information to the performance of our business and therefore we use it to supplement our GAAP reporting. We have chosen to provide this supplemental information to investors, analysts and other interested parties to enable them to perform additional analyses of operating results.

Adjusted EBITDA:

We believe that adjusted EBITDA, which excludes certain identified items that we do not consider to be part of our ongoing business, improves the comparability of year to year results, and is representative of our underlying performance. Management uses this information to assess and measure the performance of our operating segments. We have chosen to provide this supplemental information to investors, analysts and other interested parties to enable them to perform additional analyses of operating results, to illustrate the results of operations giving effect to the non-GAAP adjustments shown in the below reconciliations, and to provide an additional measure of performance.

Manufacturing Cash, Cash Equivalents, and Marketable Securities:

Manufacturing cash, cash equivalents, and marketable securities represents the Company’s consolidated cash, cash equivalents, and marketable securities excluding cash, cash equivalents, and marketable securities of our financial services operations. We include marketable securities with our cash and cash equivalents when assessing our liquidity position as our investments are highly liquid in nature. We have chosen to provide this supplemental information to investors, analysts and other interested parties to enable them to perform additional analyses of our ability to meet our operating requirements, capital expenditures, equity investments, and financial obligations.

Structural costs consists of Selling, general and administrative expenses and Engineering and product development costs.

EBITDA reconciliation:

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Adjusted EBITDA reconciliation:

The above items did not have a material impact on taxes due to the valuation allowances on our U.S. and Brazil deferred tax assets.

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Manufacturing segment cash and cash equivalents and marketable securities reconciliation:

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