NOTE A – Basis of Presentation

The accompanying unaudited consolidated financial statements have been prepared in accordance with generally accepted accounting principles (GAAP) for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. In the opinion of management, all adjustments (consisting of normal recurring accruals) considered necessary for a fair presentation have been included. Operating results for the three and nine months ended September 30, 2013 are not necessarily indicative of the results that may be expected for the year ending December 31, 2013. For further information, refer to the consolidated financial statements and footnotes included in PACCAR Inc’s (the Company) Annual Report on Form 10-K for the year ended December 31, 2012.

Earnings per Share : Basic earnings per common share are computed by dividing earnings by the weighted average number of common shares outstanding, plus the effect of any participating securities. Diluted earnings per common share are computed assuming that all potentially dilutive securities are converted into common shares under the treasury stock method. The dilutive and antidilutive options are shown separately in the table below.

New Accounting Pronouncements : In July 2013, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) 2013-11, Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists . This ASU requires an unrecognized tax benefit, or a portion of an unrecognized tax benefit, to be presented in the consolidated financial statements as a reduction to a deferred tax asset for a net operating loss carryforward, a similar tax loss, or a tax credit carryforward if available under the applicable tax jurisdiction. The ASU is effective for annual periods beginning after December 15, 2013 and interim periods within those annual periods. The Company does not expect the adoption of the ASU to have a material impact on its consolidated financial statements.

In July 2013, the FASB issued ASU 2013-10, Inclusion of the Fed Funds Effective Swap Rate (or Overnight Index Swap Rate) as a Benchmark Interest Rate for Hedge Accounting Purposes . The amendments in this ASU permit the Fed Funds Effective Swap Rate (OIS) to be used as a U.S. benchmark interest rate for hedge accounting purposes in addition to U.S. government and London Interbank Offered Rate. The amendments also remove the restriction on using different benchmark rates for similar hedges. The ASU is effective for qualifying new or redesignated hedging relationships entered on or after July 17, 2013. The Company adopted ASU 2013-10 in the third quarter of 2013; the implementation of this amendment did not have an impact on the Company’s consolidated financial statements.

In February 2013, the FASB issued ASU 2013-02, Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income. This ASU requires disclosure of additional information about reclassification adjustments from other comprehensive income. The ASU is effective for annual periods beginning on or after January 1, 2013 and interim periods within those annual periods. The Company adopted ASU 2013-02 in the first quarter of 2013; the implementation of this amendment resulted in additional disclosures (see Note F), but did not have an impact on the Company’s consolidated financial statements.

In January 2013, the FASB issued ASU 2013-01, Clarifying the Scope of Disclosures about Offsetting Assets and Liabilities , an update to ASU 2011-11, Disclosures about Offsetting Assets and Liabilities .

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The ASUs require entities with derivatives, repurchase agreements and securities borrowing and lending transactions that are either offset on the balance sheet, or subject to a master netting arrangement, to provide expanded disclosures about the nature of the rights of offset. The updated ASU is effective for annual periods beginning on or after January 1, 2013 and interim periods within those annual periods. The Company adopted ASU 2013-01 in the first quarter of 2013; the implementation of this amendment resulted in additional disclosures (see Note I), but did not have an impact on the Company’s consolidated financial statements.

NOTE B – Investments in Marketable Debt Securities

The Company’s investments in marketable debt securities are classified as available-for-sale. These investments are stated at fair value with any unrealized gains or losses, net of tax, included as a component of accumulated other comprehensive loss.

The Company utilizes third-party pricing services for all of its marketable debt security valuations. The Company reviews the pricing methodology used by the third-party pricing services including the manner employed to collect market information. On a quarterly basis, the Company also performs review and validation procedures on the pricing information received from the third-party providers. These procedures help ensure that the fair value information used by the Company is determined in accordance with applicable accounting guidance.

The Company evaluates its investment in marketable debt securities at the end of each reporting period to determine if a decline in fair value is other than temporary. Realized losses are recognized upon management’s determination that a decline in fair value is other than temporary. The determination of other-than-temporary impairment is a subjective process, requiring the use of judgments and assumptions regarding the amount and timing of recovery. The Company reviews and evaluates its investments at least quarterly to identify investments that have indications of other-than-temporary impairments. It is reasonably possible that a change in estimate could occur in the near term relating to other-than-temporary impairment. Accordingly, the Company considers several factors when evaluating debt securities for other-than-temporary impairment, including whether the decline in fair value of the security is due to increased default risk for the specific issuer or market interest rate risk.

In assessing default risk, the Company considers the collectability of principal and interest payments by monitoring changes to issuers’ credit ratings, specific credit events associated with individual issuers as well as the credit ratings of any financial guarantor, and the extent and duration to which amortized cost exceeds fair value.

In assessing market interest rate risk, including benchmark interest rates and credit spreads, the Company considers its intent for selling the securities and whether it is more likely than not the Company will be able to hold these securities until the recovery of any unrealized losses.

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The cost of marketable debt securities is adjusted for amortization of premiums and accretion of discounts to maturity. Amortization, accretion, interest and dividend income and realized gains and losses are included in investment income. The cost of securities sold is based on the specific identification method. The proceeds from sales and maturities of marketable securities for the nine months ended September 30, 2013 and 2012 were $628.5 and $445.8, respectively. Gross realized gains were $1.7 and $1.9 for the nine months ended September 30, 2013 and 2012, respectively, and gross realized losses were $.5 and $.1 for the nine months ended September 30, 2013 and 2012, respectively.

The fair value of marketable debt securities that have been in an unrealized loss position for less than 12 months at September 30, 2013 was $246.1 and the associated unrealized loss was $.7. The fair value of marketable debt securities that have been in an unrealized loss position for less than 12 months at December 31, 2012 was $291.0 and the associated unrealized loss was $.4. The fair value of marketable debt securities that have been in an unrealized loss position for 12 months or greater at September 30, 2013 was $1.0 and the associated unrealized loss was less than $.1. There were no marketable debt securities that were in an unrealized loss position for 12 months or greater at December 31, 2012.

For the investment securities in gross unrealized loss positions identified above, the Company does not intend to sell the investment securities. It is more likely than not that the Company will not be required to sell the investment securities before recovery of the unrealized losses, and the Company expects that the contractual principal and interest will be received on the investment securities. As a result, the Company recognized no other-than-temporary impairments during the periods presented.

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NOTE C – Inventories

Inventories are stated at the lower of cost or market. Cost of inventories in the U.S. is determined principally by the last-in, first-out (LIFO) method. Cost of all other inventories is determined principally by the first-in, first-out (FIFO) method.

Inventories include the following:

Under the LIFO method of accounting (used for approximately 48% of September 30, 2013 inventories), an actual valuation can be made only at the end of each year based on year-end inventory levels and costs. Accordingly, interim valuations are based on management’s estimates of those year-end amounts.

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Recognition of interest income and rental revenue is suspended (put on non-accrual status) when the receivable becomes more than 90 days past the contractual due date or earlier if some other event causes the Company to determine that collection is not probable. Accordingly, no finance receivables more than 90 days past due were accruing interest at September 30, 2013 or December 31, 2012. Recognition is resumed if the receivable becomes current by the payment of all amounts due under the terms of the existing contract and collection of remaining amounts is considered probable (if not contractually modified) or if the customer makes scheduled payments for three months and collection of remaining amounts is considered probable (if contractually modified). Payments received while the finance receivable is impaired or on non-accrual status are applied to interest and principal in accordance with the contractual terms.

Allowance for Credit Losses

The Company continuously monitors the payment performance of all its finance receivables. For large retail finance customers and dealers with wholesale financing, the Company regularly reviews their financial statements and makes site visits and phone contact as appropriate. If the Company becomes aware of circumstances that could cause those customers or dealers to face financial difficulty, whether or not they are past due, the customers are placed on a watch list.

The Company modifies loans and finance leases as a normal part of its Financial Services operations. The Company may modify loans and finance leases for commercial reasons or for credit reasons. Modifications for commercial reasons are changes to contract terms for customers that are not considered to be in financial difficulty. Modifications for credit reasons are changes to contract terms for customers considered to be in financial difficulty. The Company’s modifications typically result in granting more time to pay the contractual amounts owed and charging a fee and interest for the term of the modification.

When considering whether to modify customer accounts for credit reasons, the Company evaluates the creditworthiness of the customers and modifies those accounts that the Company considers likely to perform under the modified terms. When the Company modifies loans and finance leases for credit reasons and grants a concession, the modifications are classified as troubled debt restructurings (TDRs). The Company does not typically grant credit modifications for customers that do not meet minimum underwriting standards since the Company normally repossesses the financed equipment in these circumstances. When such modifications do occur, they are considered TDRs.

On average, modifications extended contractual terms by approximately six months in 2013 and seven months in 2012 and did not have a significant effect on the weighted average term or interest rate of the total portfolio at September 30, 2013 and December 31, 2012.

The Company has developed a systematic methodology for determining the allowance for credit losses for its two portfolio segments, retail and wholesale. The retail segment consists of retail loans and direct and sales-type finance leases, net of unearned interest. The wholesale segment consists of truck inventory financing loans to dealers that are collateralized by trucks and other collateral. The wholesale segment generally has less risk than the retail segment. Wholesale receivables generally are shorter in duration than retail receivables, and the Company requires monthly reporting of the wholesale dealer’s financial condition, conducts periodic audits of the trucks being financed and in many cases, obtains personal guarantees or other security such as dealership assets. In determining the allowance for credit losses, retail loans and finance leases are evaluated together since they relate to a similar customer base, their contractual terms require regular payment of principal and interest generally over 36 to 60 months and they are secured by the same type of collateral. The allowance for credit losses consists of both specific and general reserves.

The Company individually evaluates certain finance receivables for impairment. Finance receivables that are evaluated individually for impairment consist of all wholesale accounts and certain large retail accounts with past due balances or otherwise determined to be at a higher risk of loss. A finance receivable is impaired if it is considered probable the Company will be unable to collect all contractual interest and principal payments as scheduled. In addition, all retail loans and leases which have been

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classified as TDRs and all customer accounts over 90 days past due are considered impaired. Generally, impaired accounts are on non-accrual status. Impaired accounts classified as TDRs which have been performing for 90 consecutive days are placed on accrual status if it is deemed probable that the Company will collect all principal and interest payments.

Impaired receivables are considered collateral dependent. Large balance retail and all wholesale impaired receivables are individually evaluated to determine the appropriate reserve for losses. The determination of reserves for large balance impaired receivables considers the fair value of the associated collateral. When the underlying collateral fair value exceeds the Company’s recorded investment, no reserve is recorded. Small balance impaired receivables with similar risk characteristics are evaluated as a separate pool to determine the appropriate reserve for losses using the historical loss information discussed below.

For finance receivables that are not individually impaired, the Company collectively evaluates and determines the general allowance for credit losses for both retail and wholesale receivables based on historical loss information, using past-due account data and current market conditions. Information used includes assumptions regarding the likelihood of collecting current and past-due accounts, repossession rates, the recovery rate on the underlying collateral based on used truck values and other pledged collateral or recourse. The Company has developed a range of loss estimates for each of its country portfolios based on historical experience, taking into account loss frequency and severity in both strong and weak truck market conditions. A projection is made of the range of estimated credit losses inherent in the portfolio from which an amount is determined as probable based on current market conditions and other factors impacting the creditworthiness of the Company’s borrowers and their ability to repay. After determining the appropriate level of the allowance for credit losses, a provision for losses on finance receivables is charged to income as necessary to reflect management’s estimate of incurred credit losses, net of recoveries, inherent in the portfolio.

In determining the fair value of the collateral, the Company uses a pricing matrix and categorizes the fair value as Level 2 in the hierarchy of fair value measurement. The pricing matrix is reviewed quarterly and updated as appropriate. The pricing matrix considers the make, model and year of the equipment as well as recent sales prices of comparable equipment through wholesale channels to the Company’s dealers (principal market). The fair value of the collateral also considers the overall condition of the equipment.

Accounts are charged-off against the allowance for credit losses when, in the judgment of management, they are considered uncollectable (generally upon repossession of the collateral). Typically the timing between the repossession and charge-off is not significant. In cases where repossession is delayed (e.g., for legal proceedings), the Company records partial charge-offs. The charge-off is determined by comparing the fair value of the collateral, less cost to sell, to the recorded investment.

For the following credit quality disclosures, finance receivables are classified as dealer wholesale, dealer retail and customer retail segments. The dealer wholesale segment consists of truck inventory financing to PACCAR dealers. The dealer retail segment consists of loans and leases to participating dealers and franchises that use the proceeds to fund customers’ acquisition of commercial vehicles and related equipment. The customer retail segment consists of loans and leases directly to customers for the acquisition of commercial vehicles and related equipment. Customer retail receivables are further segregated between fleet and owner/operator classes. The fleet class consists of customer retail accounts operating more than five trucks. All other customer retail accounts are considered owner/operator. Each individual class has similar measurement attributes, risk characteristics and common methods to monitor and assess credit risk.

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* Operating lease and other trade receivables.

Information regarding finance receivables evaluated and determined individually and collectively is as follows:

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