UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K/A

For the fiscal year ended December 31, 2010

or

For transition period from              to             

Commission File No. 001-11677

PACCAR FINANCIAL CORP.

(Exact name of Registrant as specified in its charter)

Registrant’s telephone number, including area code is (425) 468-7100

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.    Yes:  x    No:  ¨

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.    Yes:  ¨    No:  x

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    Yes:  x    No:  ¨.

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).    Yes:  ¨    No:  ¨

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K (§229.405 of this chapter) is not contained herein, and will not be contained, to the best of registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K.  x

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See definition of “large accelerated filer”, “accelerated filer”, “smaller reporting company” in Rule 12b-2 of the Exchange Act.

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12(b)-2 of the Act).    Yes:  ¨    No:  x

The aggregate market value of the voting stock held by non-affiliates of the registrant as of June 30, 2010:  None

The number of shares outstanding of the registrant’s classes of common stock as of January 31, 2011:

Common Stock, $100 par value—145,000 shares

THE REGISTRANT IS A WHOLLY-OWNED INDIRECT SUBSIDIARY OF PACCAR INC AND MEETS THE CONDITIONS SET FORTH IN GENERAL INSTRUCTIONS (I) (1) (a) AND (b) OF FORM 10-K AND IS, THEREFORE, FILING THIS FORM WITH THE REDUCED DISCLOSURE FORMAT.

PACCAR Financial Corp.

EXPLANATORY NOTE

PACCAR Financial Corp. (the “Company”) is filing this Amendment No. 1 on Form 10-K/A to its Form 10-K for the fiscal year ended December 31, 2010 filed with the Securities and Exchange Commission (the “SEC”) on March 1, 2011 (the “Original Filing”) to amend the disclosure contained in the paragraph captioned “Customer Concentration” under Item 1 and 1A, “Business and Risk Factors” on page 6 of the Original Filing solely to include the name of the customer that accounted for greater than 10% of total Interest and Other Revenue . The third sentence of that paragraph is hereby amended to read as follows: “The Company had contractual arrangements with one customer, Swift Transportation Corporation, that accounted for 11.4% and 11.8% of total Interest and Other Revenue for the periods ended December 31, 2010 and 2009, respectively.”

This Amendment does not update any disclosures to reflect developments since the filing date of the Original Filing. Accordingly, this Amendment should be read in conjunction with the Original Filing and the Company’s other filings made with the SEC on or subsequent to March 1, 2011.

The complete Form 10-K/A, including the amended Item 1 and 1A, will be available at the Company’s website and on the SEC’s website at www.sec.gov.

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PART I

ITEM 1 AND 1A. BUSINESS AND RISK FACTORS

GENERAL

PACCAR Financial Corp.

PACCAR Financial Corp. (the “Company”), a Washington corporation, was incorporated in 1961 as a wholly-owned subsidiary of PACCAR Inc (“PACCAR”) to finance the sale of PACCAR products. In 2000, PACCAR transferred the stock of the Company to PACCAR Financial Services Corporation (“PFSC”), a wholly-owned subsidiary of PACCAR.

The Company principally provides financing and leasing of PACCAR manufactured trucks and other transportation equipment sold through Kenworth’s and Peterbilt’s independent dealer network in the United States. The Company also finances dealer inventories of new and used transportation equipment. The Company’s PacLease division franchises Kenworth and Peterbilt dealerships to engage in full-service and finance leasing. In selected markets, PacLease directly engages in full-service leasing with its customers through Company-owned stores and on a limited basis through Kenworth and Peterbilt dealerships.

PACCAR

PACCAR has two principal industry segments: (1) design, manufacture and distribution of high-quality, light-, medium- and heavy-duty commercial trucks and related aftermarket parts and (2) finance and leasing services provided to customers and dealers. Light and medium-duty trucks have a gross vehicle weight (GVW) ranging from 16,000 to 33,000 lbs (Class 5 to 7) in North America and 6 to 15 metric tonnes in Europe. Heavy duty trucks have a GVW of over 33,000 lbs (Class 8) in North America and over 15 metric tonnes in Europe. PACCAR’s finance and leasing activities are principally related to PACCAR products and associated equipment. Other manufactured products include industrial winches.

PACCAR and its subsidiaries design and manufacture heavy-duty diesel trucks which are marketed under the Kenworth, Peterbilt and DAF nameplates. These trucks, which are built in three plants in the United States, three in Europe and one each in Australia, Canada and Mexico, are used world-wide for over-the-road and off-highway hauling of freight, petroleum, wood products, construction and other materials. PACCAR competes in the North American Class 5 to 7 markets primarily with conventional models. These trucks are assembled at facilities in Ste. Therese, Canada and in Mexicali, Mexico, which are operated by PACCAR’s wholly-owned subsidiaries located in those countries. PACCAR competes in the European light/medium market with DAF cab-over-engine trucks assembled in the United Kingdom by Leyland, one of PACCAR’s wholly-owned subsidiaries. Commercial trucks and related aftermarket parts comprise the largest segment of PACCAR’s business, accounting for 89.7% of total 2010 net sales and revenues.

Substantially all trucks and related aftermarket parts are sold to independent dealers. The Kenworth and Peterbilt nameplates are marketed and distributed by separate divisions in the U.S. and a foreign subsidiary in Canada. The Kenworth nameplate is also marketed and distributed by foreign subsidiaries in Mexico and Australia. The DAF nameplate is marketed and distributed by a foreign subsidiary headquartered in The Netherlands. A U.S. division, PACCAR International, also markets all three nameplates outside each of their primary markets. The decision to operate as a subsidiary or as a division is incidental to PACCAR’s Truck Segment operations and reflects legal, tax and regulatory requirements in the various countries where PACCAR operates.

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Aftermarket truck parts are sold and delivered to Kenworth’s and Peterbilt’s independent dealers through PACCAR’s parts distribution network. Parts are both manufactured by PACCAR and purchased from various suppliers. Aftermarket parts inventory levels are determined largely by anticipated customer demand and the need for timely delivery. As a percentage of total consolidated net sales and revenues, parts sales were 21.3% in 2010, 23.4% in 2009 and 15.1% in 2008.

There were three other principal competitors in the U.S. and Canada Class 8 truck market in 2010. PACCAR’s share of the U.S. and Canadian market was 24.1% of retail sales in 2010. In Europe there were five other principal competitors in the commercial vehicle market in 2010, including parent companies to two competitors of PACCAR in the United States. In 2010, DAF had a record 15.2% share of the Western and Central European heavy-duty market and a 7.7% share of the light/medium market. These markets are highly competitive in price, quality and service, and PACCAR is not dependent on any single customer for its sales. There are no significant seasonal variations in sales.

In addition to the Company, which provides financing, leasing and full-service truck leasing in the United States, PACCAR offers similar financing programs for PACCAR products through other wholly-owned finance companies in Mexico, Canada, Australia, the United Kingdom, and Continental Europe. PACCAR also conducts full-service leasing operations through wholly-owned subsidiaries in Canada, Mexico and Germany.

PACCAR’s common stock is traded on the NASDAQ Global Select Market under the symbol PCAR. PACCAR and the Company are subject to the informational requirements of the Securities Exchange Act of 1934 and, in accordance therewith, file reports and other information with the Securities and Exchange Commission (the “Commission”). All reports, proxy statements and other information filed by PACCAR and the Company with the Commission may be inspected and copied at the public reference facility maintained by the Commission at 100 F Street, N.E., Washington, D.C. 20549 or through the Commission’s internet site at www.sec.gov.

BUSINESS OF THE COMPANY

The Company operates primarily in the industry segment of finance and leasing services provided to customers and dealers in the United States for new Kenworth and Peterbilt trucks, used trucks, truck trailers and allied equipment. The Company’s PacLease division franchises Kenworth and Peterbilt dealerships to engage in full-service and finance leasing. In selected markets, PacLease directly engages in full-service leasing with its customers through Company-owned stores and on a limited basis through Kenworth and Peterbilt dealerships.

The Company conducts business with most Kenworth and Peterbilt dealers in the United States. The volume of the Company’s business is significantly affected by PACCAR’s sales of trucks to its dealers and competition from other financing sources.

As of December 31, 2010, the Company employed 252 full-time employees, none of whom are represented by a collective bargaining agent. The Company considers relations with its employees to be good.

RISK FACTORS

The Company is exposed to certain risks and uncertainties that could have a material adverse impact to the Company’s financial condition and operating results, including:

Sales of PACCAR Products

The Company’s business is substantially dependent upon the sale of PACCAR products and its ability to offer competitive financing in the United States. Changes in the volume of sales of PACCAR products due to a variety of reasons could impact the level of business of the Company. Refer to the “Relationship with PACCAR and Affiliates” section in this Business and Risk Factors section and “Note D – Transactions with PACCAR and Affiliates” in the Notes to the Financial Statements for further discussion regarding the Company’s relationship with PACCAR.

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Credit Risk

Credit risk, including counterparty credit risk in derivative transactions, is the risk of loss arising from the failure of a customer, dealer or counterparty to meet the terms of any contract with the Company or otherwise fail to perform as agreed. The Company may be exposed to a greater credit risk in periods of adverse economic conditions, such as high interest rates, limited credit availability, high diesel prices or a decline in freight demand, since it becomes more difficult for some customers and dealers to perform as agreed. These conditions could also cause a decrease in the value of the Company’s collateral. Refer to Note E – Derivative Financial Instruments in the Notes to the Financial Statements for further discussion regarding the Company’s exposure to counterparty risk. Refer to Item 7 – Management’s Discussion and Analysis of Financial Condition and Results of Operations for further discussion of credit losses.

Residual Value Risk

Residual value risk is the risk that the estimated residual value of leased assets established at lease origination, for the Company’s operating leases and certain direct financing leases, will not be recoverable when the leased asset is returned to the Company. When the market value of these leased assets at contract maturity or at early termination is less than its contractual residual value, the Company will be exposed to a greater risk of loss on the sales of the returned equipment. Refer to the Critical Accounting Policy on “Equipment on Operating Leases” in Item 7 – Management’s Discussion and Analysis of Financial Condition and Results of Operations for further discussion regarding the Company’s exposure to residual value risk.

Market Risk

Market risk is the risk that changes in market interest rates, liquidity or prices will negatively impact the Company’s operating results and access to capital. Policies governing market risk exposure are established and periodically reviewed by the Company’s senior management. Refer to Item 7A - Quantitative and Qualitative Disclosures about Market Risk for further discussion regarding the Company’s exposure to interest rate risk.

THE COMPANY’S PRODUCTS

The Company offers the following products to retail customers:

Retail Contracts and Loans The Company purchases contracts from dealers and receives assignments of the contracts and a first lien security interest in the vehicles financed (“Retail Contracts”). Certain Retail Contracts with third party leasing companies may also include an assignment to the Company of the related lease and rental payments due. Retail Contracts purchased by the Company have fixed or floating interest rates.

The Company also makes loans to the end users of the vehicles financed that are secured by a first lien security interest in the vehicles (“Loans”). Loans have fixed or floating interest rates.

Direct Financing Leases The Company offers direct financing lease contracts where it is treated as the owner of the equipment for tax purposes and generally retains the tax depreciation (“Direct Financing Leases”). The lessee is responsible for the payment of property and sales taxes, licenses, maintenance and other operating costs. The lessee is obligated to maintain the equipment and to insure the equipment against physical damage and liability losses.

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Most of the Company’s Direct Financing Leases contain a Terminal Rental Adjustment Clause, which requires the lessee to guarantee to the Company a stated residual value upon disposition of the equipment at the end of the direct financing lease term.

Operating Leases The Company offers operating lease contracts (“Operating Leases”) where the Company owns the equipment. The lessee is responsible for the payment of property and sales taxes, licenses, maintenance and other operating costs. The lessee is obligated to maintain the equipment and to insure the equipment against casualty and liability losses.

At the end of the operating lease term, the lessee has the option to return the equipment to the Company or purchase the equipment at its fair market value.

Insurance The Company’s PacLease business offers physical damage and liability insurance on new and used trucks and trailers to its full-service lease customers. To limit its exposure the Company has acquired insurance coverage for losses above specified levels from a third party insurance carrier.

The Company offers the following products to Kenworth and Peterbilt dealers and PacLease franchisees:

Master Notes Master note contracts (“Master Notes”) are offered to select dealers for new and used trucks. Retail installment contracts originated by the dealer for new or used trucks which meet the Company’s requirement as to form, terms and creditworthiness for Retail Contracts are pledged to the Company as collateral for direct, full recourse loans by the Company to the dealer. Master Notes have fixed or floating interest rates.

Wholesale Contracts The Company provides wholesale financing for new and used truck and trailer inventories for dealers (“Wholesale Contracts”). Wholesale Contracts are secured by the inventories financed. The amount of credit extended by the Company for each truck is generally limited to the invoice price of new equipment and to the wholesale value of used equipment. Wholesale Contracts have floating interest rates.

Dealer Loans The Company makes secured loans to selected Peterbilt and Kenworth dealers (“Dealer Loans”). The purpose of these loans includes the financing of real estate, fixed assets, working capital and dealership acquisitions. Dealer Loans have fixed or floating interest rates.

Full-Service Leasing The Company also conducts full-service leasing operations under the PacLease trade name. Selected dealers are franchised to provide full-service leasing, which includes the equipment, maintenance, parts, taxes and licenses all in a combined contract with the customer. The Company provides the franchisees with equipment financing and managerial support. The Company also operates full-service lease outlets in selected markets on its own behalf.

Insurance The Company charges a fee to provide insurance coverage, through an unrelated regulated insurance carrier, on new trucks, used trucks and trailer inventory to dealers having Wholesale Contracts with the Company.

CUSTOMER CONCENTRATION, PAST-DUE ACCOUNTS AND LOSS EXPERIENCE

Customer Concentration

The Company’s customers are concentrated in the transportation industry throughout the United States. The Company does not have contractual arrangements with any one party (customers, dealers and/or franchises) that account for 10% or more of Finance and Lease Receivables for the periods ended December 31, 2010, 2009 and 2008. The Company had contractual arrangements with one customer, Swift Transportation Corporation, that accounted for 11.4% and 11.8% of total Interest and Other Revenue for the periods ended December 31, 2010 and 2009, respectively. No one party accounted for 10% or more of total Interest and Other Revenue for the period ended December 31, 2008.

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PACCAR Financial Corp.

Past-Due Receivables and Allowance for Losses

An account is considered past-due by the Company if any portion of an installment is due and unpaid for more than 30 days. In periods of adverse economic conditions, past-due levels, repossessions and credit losses generally increase.

The provision for losses on finance and other receivables is charged to income based on management’s estimate of incurred credit losses, net of recoveries, inherent in the portfolio. Receivables are charged off to the allowance for losses when, in the judgment of management, they are considered uncollectible (generally upon repossession of the collateral).

For further discussion of the allowance for losses, see Item 7 - Management’s Discussion and Analysis of Financial Condition and Results of Operations.

COMPETITION AND ECONOMIC FACTORS

The commercial truck and trailer finance and leasing business is highly competitive among banks, commercial finance companies, captive finance companies and leasing companies. Some of these institutions have substantially greater financial resources than the Company and may borrow funds at lower rates.

The dealers are the primary source of contracts acquired by the Company. However, dealers are not required to obtain financing from the Company and they have a variety of other sources that may be used for wholesale and customer financing of trucks. Retail purchasers also have a variety of sources available to finance truck purchases.

The ability of the Company to compete in its market is principally based on the rates, terms and conditions that the Company offers dealers and retail purchasers, as well as the specialized services it provides. Rates, terms and conditions are based on the Company’s desire to provide flexible financing and services to satisfy dealer and customer needs, the ability of the Company to borrow funds at competitive rates and the Company’s need to earn an adequate return on its invested capital. The Company’s business is also affected by changes in market interest rates and used truck values, which in turn are related to general economic conditions, demand for credit, inflation and governmental policies. Seasonality is not a significant factor in the Company’s business.

The volume of receivables available to be acquired by the Company from dealers is largely dependent upon the number of Kenworth and Peterbilt trucks sold in the United States. Sales of medium- and heavy-duty trucks depend on the capital equipment requirements of the transportation industry, which in turn are influenced by growth and cyclical variations in the economy. Medium- and heavy-duty truck sales are also sensitive to economic factors such as fuel costs, interest rates, insurance premiums, federal excise and highway use taxes, taxation on the acquisition and use of capital goods, as well as government regulations.

REGULATION AND SIMILAR MATTERS

In certain states, the Company is subject to retail installment sales or installment loan statutes and related regulations, the terms of which vary from state to state. These laws may require the Company to be licensed as a sales finance company and may regulate disclosure of finance charges and other terms of retail installment contracts. The Company is subject to substantive state franchise regulations and federal and state uniform franchise disclosure laws in connection with the offering of PacLease full-service truck leasing and rental franchises to Kenworth and Peterbilt truck dealers. The Company also owns and operates several truck leasing and rental business locations, which are subject to applicable state licensing laws. The Company is also subject to certain provisions of federal law relating to non-discrimination in the granting of credit.

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PACCAR Financial Corp.

SOURCES OF FUNDS

The Company’s primary sources of funds are commercial paper and medium-term note borrowings in the public capital markets, collections on loans and leases, retained earnings and to a lesser extent borrowings from PACCAR, bank loans and capital contributions from PFSC. The Company’s investment in additional receivables is dependent upon its ability to raise funds at competitive rates in the public and private debt markets. The receivables and leases that are financed are either fixed rate or floating rate with terms that generally range from 36 to 60 months.

To reduce the risk of changes in interest rates that could affect interest margins, the Company obtains funds with interest rate characteristics similar to the corresponding assets. Fixed rate assets are primarily funded with fixed and floating rate medium-term notes and commercial paper. Interest rate swaps are combined with commercial paper or floating rate medium-term notes to convert floating rate debt to fixed rate debt to achieve the Company’s match funding objectives. Floating rate assets are funded primarily with commercial paper with maturities of three months or less and floating rate medium-term notes.

As of December 31, 2010, the total notional principal amount of interest rate swap contracts outstanding was $845.0, all of which effectively resulted in a net fixed rate payment obligation. These swap contracts are accounted for as cash flow hedges.

A portion of the Company’s fixed-rate term notes has been converted to variable-rate term notes using fair value hedges for interest rate risk. Fair value is determined using modeling techniques that include market inputs for interest rates. As of December 31, 2010, the total notional principal amount of fair value swap contracts outstanding was $40.0, all of which result in a net floating rate payment obligation.

The notional amounts are used to measure the volume of these contracts and do not represent exposure to credit loss. The permitted types of interest rate swap contracts, counterparties’ transaction limits and related approval authorizations have been established by the Company’s senior management and Board of Directors. The interest rate contracts outstanding are regularly reported to, and reviewed by, the Company’s senior management.

The Company participates with PACCAR and certain other PACCAR affiliates in syndicated credit facilities of $3,000 at December 31, 2010. Of this amount, $1,000 expires in June 2011, $1,000 expires in 2012 and $1,000 expires in 2013. PACCAR and the Company intend to replace these credit facilities as they expire with facilities of similar amounts. Of these, credit facilities of $2,135 are available for use by the Company and/or PACCAR and certain other PACCAR affiliates. The remaining $865 is allocated to the following subsidiaries: $360 is available for use by PACCAR’s Canadian financial subsidiary, $200 is available for use by PACCAR’s Mexican financial subsidiaries, $155 is available for use by PACCAR’s Australian financial subsidiary and $150 is available for use by PACCAR’s United Kingdom financial subsidiary. These credit facilities are used to provide backup liquidity for the Company’s commercial paper and maturing medium-term notes. The Company is liable only for its own borrowings under these credit facilities. There were no borrowings under these credit facilities in the years ended December 31, 2010 and 2009.

As of December 31, 2010, the Company had medium-term notes outstanding with a notional value of $1,123.5 under two shelf registration statements, of which $323.5 are due within 12 months. See “Note F – Borrowings” in the Notes to the Financial Statements for further information on the Company’s medium-term notes.

An indenture of the Company dated as of December 1, 1983, as amended by a first supplemental indenture dated June 19, 1989 (Exhibit 4.1(a)) and a second indenture dated November 20, 2009 (Exhibit 4.1(c)) with respect to the Company’s medium-term notes, which are publicly issued from time to time, contain restrictions limiting secured debt which may be incurred by the Company and any subsidiary.

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RELATIONSHIP WITH PACCAR AND AFFILIATES

General

The operations of the Company are fundamentally affected by its relationship with PACCAR. Sales of PACCAR products are the Company’s principal source of its financing business. The Company receives administrative support from and pays dividends to PFSC and periodically borrows funds from or lends money to PACCAR and/or its affiliates. The Company’s principal office is located in the corporate headquarters building of PACCAR (owned by PACCAR). The Company also leases office space from one facility owned by PACCAR and five facilities leased by PACCAR. Since the directors of the Company are all executives of PACCAR and PACCAR is the sole owner of PFSC’s outstanding voting common stock, PACCAR can determine the course of the Company’s business.

Periodically, the Company makes loans to, borrows from and has intercompany transactions with PACCAR. The Company had $395.0 outstanding in loans due to PACCAR as of December 31, 2010 and 2009. The Company had $228.8 and $52.0 outstanding in loans due from PACCAR as of December 31, 2010 and 2009, respectively. In addition, the Company loans funds to certain foreign finance and leasing affiliates of PACCAR. The Company had $197.7 and $266.6 outstanding in loans due from foreign finance and leasing affiliates of PACCAR as of December 31, 2010 and 2009, respectively. These various affiliates have Support Agreements with PACCAR, similar to the Company’s Support Agreement with PACCAR described below. The foreign affiliates operate in the United Kingdom, The Netherlands, Mexico, Canada and Australia, and any resulting currency exposure is fully hedged. The foreign affiliates primarily provide financing and leasing of PACCAR-manufactured trucks and related equipment sold through DAF’s, Kenworth’s and Peterbilt’s independent dealer networks in Europe, Mexico, Canada and Australia. The Company will not make loans to the foreign affiliates in excess of the equivalent of $500.0 United States dollars, unless the amount in excess of such limit is guaranteed by PACCAR. The Company periodically reviews the funding alternatives for these affiliates, and these limits may be revised in the future.

PFSC charges the Company for certain administrative services it provides and certain services the Company receives indirectly from PACCAR. As of December 31, 2010, PFSC employed 146 full-time employees, none of whom are represented by a collective bargaining agent. The costs are charged to the Company based upon the Company’s specific use of the services at PFSC’s or PACCAR’s cost. Management considers these charges reasonable and similar to the costs that would be incurred if the Company were on a stand-alone basis. See “Note D – Transactions with PACCAR and Affiliates” in the Notes to Financial Statements.

Support Agreement

The Company and PACCAR are parties to a Support Agreement that obligates PACCAR to provide, when required, financial assistance to the Company to assure that the Company maintains a ratio of net earnings available for fixed charges to fixed charges (as defined in the Support Agreement) of at least 1.25 to 1 for any fiscal year. The Support Agreement also requires PACCAR to own, directly or indirectly, all outstanding voting stock of the Company. The required ratio was met for the years ended December 31, 2010, 2009 and 2008 without assistance. See “Note D – Transactions with PACCAR and Affiliates” in the Notes to Financial Statements.

The Company and PACCAR may amend or terminate any or all of the provisions of the Support Agreement upon 30 days notice, with copies of the notice being sent to all nationally recognized statistical rating organizations (“NRSROs”) which have issued ratings with respect to debt of the Company (“Rated Debt”). Such amendment or termination will be effective only if (i) two NRSROs confirm in writing that their ratings with respect to any Rated Debt would remain the same after such amendment or termination, or (ii) the notice of amendment or termination provides that the Support Agreement will continue in effect with respect to Rated Debt outstanding on the effective date of such amendment or termination unless such debt has been paid or defeased pursuant to the indenture or other agreement applicable to such debt, or (iii) the holders of at least two-thirds of the aggregate

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principal amount of all outstanding Rated Debt with an original maturity in excess of 270 days consent in writing to such amendment or termination, provided that the holders of Rated Debt having an original maturity of 270 days or less shall continue to have the benefits of the Support Agreement until the maturity of such debt.

The Support Agreement expressly states that PACCAR’s commitments to the Company thereunder do not constitute a PACCAR guarantee of payment of any indebtedness or liability of the Company to others and do not create rights against PACCAR in favor of persons other than the Company. There are no guarantees, direct or indirect, by PACCAR of payment of any indebtedness of the Company.

OTHER DISCLOSURES

The Company’s filings on Forms 10-K, 10-Q and 8-K and any amendments to those reports can be obtained through a link on the Company’s website, www.paccarfinancial.com, or PACCAR Inc’s website, www.paccar.com, free of charge as soon as reasonably practicable after the report is electronically filed with, or furnished to, the Commission. The information on the websites is not incorporated by reference into this report.

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SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Date August 5, 2011

Pursuant to the requirements of the Securities Exchange Act of 1934, this report has been signed below by the following persons on behalf of the registrant as of the above date and in the capacities indicated.

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EXHIBIT INDEX

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