Thirteenth Annual Global High Yield Conference

September 2005

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Forward Looking Statements

This presentation contains forward-looking statements that involve known and unknown risks and uncertainties. Forward-looking statements are identified by words or phrases such as “believes,” “expects,” “anticipates,” “estimates,” “should,” “could,” “plans,” “intends,” ”will,” variations of such words and phrases, and other similar expressions. While these forward-looking statements are made in good faith, and reflect the Company’s current judgment regarding such matters, actual results could vary materially from the forward-looking statements. Important factors that could cause actual results to differ from forward-looking statements include, the risk that the pipeline acquisition and the acquisition of Dial Oil Company will not result in additional growth or increased profitability for our Four Corners operations, the risk that it will not be possible to place the acquired pipeline system in operation and/or operate the Bloomfield and Ciniza refineries at maximum rates due to financial, operational or other constraints, the risk that the timetable for placing the pipeline system into operation will be different than anticipated, the risk that it will not be possible to obtain additional crude oil for processing at the Bloomfield and Ciniza refineries at cost effective prices, the risk that the operations of Dial Oil Company will not complement our existing wholesale and retail businesses, the risk that the combination of the operations of Dial Oil Company with the operations or Phoenix Fuel will not provide a platform for future growth, the risk that we will not be able to obtain a larger credit facility should we want it, the risk that refining fundamentals will not remain more positive than the same time last year, the risk that our retail group will not continue to see fuel volumes and merchandise sales above last year’s levels, the risk that Phoenix Fuel will not continue to see stronger margins than last year or volumes consistent with the same time last year, , and other risks detailed from time to time in the Company’s filings with the Securities and Exchange Commission. All subsequent written and oral forward-looking statements attributable to the Company, or persons acting on behalf of the Company, are expressly qualified in their entirety by the foregoing. Forward-looking statements made by the Company represent its judgment on the dates such statements are made. The Company assumes no obligation to update any forward-looking statements to reflect new or changed events or circumstance.

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Company Overview

80% of EBITDA(a)

3 refineries (104,500 mbpd(b))

2 terminals Crude gathering pipeline

system Truck transports

11% of EBITDA(a)

124 convenience stores located in NM, AZ, CO(c)

9% of EBITDA(a)

One of the largest wholesale distributors in Arizona

Distribution plants Unmanned fleet fueling

locations Delivery trucks

Refining GroupRefining Group

(a) 2004 EBITDA, before corporate overhead and discontinued operations. See appendix for explanatory note and reconciliation.

(b) Total combined refining capacity.(c) As of June 30, 2005.

Phoenix FuelPhoenix FuelRetail GroupRetail Group

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Strong refining margin environment and positive long-term trends

Diversified operations and geographic markets

Proven ability to optimize operations and grow earnings

Long-term crude supply agreement for Yorktown enhances earnings and mitigates risks

Improved balance sheet

Additional growth opportunities

Key Investment Considerations

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Grow the Business

Refining Growth Evaluate divestitures from larger

competitors Consolidation of smaller

independents Evaluate refinery projects on ROCE

Retail Growth Increase market share in current

markets Enter new refinery markets

Phoenix Fuel Capitalize on supply economics and

technology to expand market share Identify acquisition opportunities to

expand geographic area (Dial Oil Co.)

Giant Strategic Objectives

Maximize ROCE

Grow the Business

Achieve & MaintainStrong Capital Structure

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Optimize operations, costs and capital spending

Identify strategic partners to improve costs and earnings

Increase crude supply to Four Corners refineries (Pipeline Acquisition)

Continue to increase merchandise and fuel sales in retail group

Continue to increase wholesale, cardlock and lubricant market share

Maximize Return on Capital Employed

Giant Strategic Objectives

Maximize ROCE

Grow the Business

Achieve & MaintainStrong Capital Structure

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Maintain Strong Capital Structure

Focus on continued debt reduction

Utilize free cash flow for debt repayment

Maintain capital discipline Strict capital planning for capital

expenditure requirements Cost effectively manage operating

and overhead costs Balanced acquisition financing

Giant Strategic Objectives

Maximize ROCE

Grow the Business

Achieve & MaintainStrong Capital Structure

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Significant Recent Debt Reduction

Giant has been disciplined about debt reduction Debt to capitalization ratio reduced from 77% to 50% Approximately $175MM of debt reduction since June 30, 2002

Balance Sheet ($MM)

6/30/2002 6/30/2005

Cash $11.6 $59.9

Debt

Revolving Credit Facility $60.0 $0.0

11% Senior Sub Notes $194.2 $127.0

9% Senior Sub Notes $150.0 $0.0

8 % Senior Sub Notes $147.6

Term Loan $38.9 $0.0

Capital Leases $6.8 $0.0

Total Debt $449.9 $274.6

Shareholders’ Equity $132.3 $270.9

Debt / Book Cap 77% 50%

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Continuing Debt Reduction

Balance Sheet ($MM)

6/30/2005 Adjustments Pro Forma

6/30/2005

Cash $59.9 $72.2

Acquisitions ($40.0)

Equity Proceeds $52.3

Debt

Revolving Credit Facility $0.0 $0.0

11% Senior Sub Notes $127.0 $127.0

9% Senior Sub Notes $0.0 $0.0

8 % Senior Sub Notes $147.6 $147.6

Total Debt $274.6 $274.6

Shareholders’ Equity $270.9 $52.3 $323.2

Debt / Book Cap 50.3% 45.9%

Net Debt /Net Book Cap 44.2% 38.5%

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2002 2003 2004

Net Income ($9.3) $11.2 $16.2

Depreciation & Amortization 35.2 36.9 37.1

Deferred Taxes 0.1 8.0 8.6

Other (0.7) 7.8 7.4

Changes in Working Capital 12.7 (1.5) 7.2

Cash Flow From Operations $38.1 $62.3 $76.5

Less: Capital Expenditures ($13.0) ($17.9) ($58.7)

Cash Flow $25.1 $44.5 $17.8

Giant made significant progress restoring financial flexibility and

improving operating performance

EBITDA ($MM)(a)

Strong Financial Performance

Cash Flow ($MM)(a)

(a) See appendix for explanatory note and reconciliation. (b) Excludes acquisitions, asset sales and insurance settlements.

(b)

2002 2003 2004

EBITDA $54.6 $102.5 $111.8

Depreciation & Amortization 35.2 36.9 37.1

EBIT $19.4 $65.6 $74.7

Interest Expense 36.3 39.0 32.9

Other (Incl. One Time Items) 2.2 6.4 14.8

Taxes (7.7) 7.9 10.7

Earnings (Cont. Ops.) ($11.5) $12.3 $16.3

Change in Accounting Principle 0.0 (0.7) 0.0

Discontinued Operations 2.3 (0.4) (0.1)

Net Income ($9.3) $11.2 $16.2

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Giant Industries: An Attractive Investment Opportunity

Strong industry fundamentals Increasing mid-cycle margins Strong operating performance Increased operating flexibility Positive impact from high-acid

crude agreement and refinancing transactions

Maximize ROCE

Grow the Business

Achieve & MaintainStrong Capital Structure

Significant leverage reduction Improved float & liquidity Valuation discount to

independent refining peers New flexibility to pursue

growth opportunities

Diversified lines of business Experienced management Growth opportunities across

all business segments

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2002 2003 2004EBITDA $54.6 $102.5 $111.8Depreciation & Amortization (35.2) (36.9) (37.1)EBIT $19.4 $65.6 $74.7Net Gain on Asset Sale 0.6 (1.8) (0.2)Gain from Insurance Settlement 3.9Interest Expense (36.3) (39.0) (32.9)Early Debt Extinguishment Costs (10.6)Financing Fee Amortization / Writeoff (3.3) (4.7) (8.3)Interest and Investment Income 0.4 0.2 0.4Income Taxes 7.7 (7.9) (10.7)Earnings from Continuing Operations ($11.5) $12.3 $16.3Change in Accounting Principle 0.0 (0.7) 0.0Discontinued Operations 2.3 (0.4) (0.1)Net Income ($9.3) $11.2 $16.2

EBITDA Reconciliation

EBITDA represents income before interest expense, interest income, income tax, and depreciation and amortization. EBITDA is not a calculation based upon generally accepted accounting principles; however, the amounts included in the EBITDA calculation are derived from amounts included in the consolidated financial statements of the Company. EBITDA should not be considered as an alternative to net income or operating income, as an indication of operating performance of the Company or as an alternative to operating cash flow as a measure of liquidity. EBITDA is not necessarily comparable to similarly titled measures of other companies.

Consolidated EBITDA ($MM) Segment EBITDA ($MM)(a)

(a) Prior to corporate overhead allocation. Segment EBITDAs do not add to consolidated total due to overheads and other reconciling items. Excludes discontinued operations.

RefiningGroup

RetailGroup

PhoenixFuel

2004 Operating Income $83.7 $6.8 $10.5

D&A 25.5 9.1 1.6

EBITDA $109.2 $15.9 $12.1

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EBIT Definition and Cash Flow Reconciliation

EBIT represents income before interest expense, interest income and income tax. EBIT is not a calculation based upon generally accepted accounting principles; however, the amounts included in the EBIT calculation are derived from amounts included in the consolidated financial statements of the Company. EBIT should not be considered as an indication of operating performance of the Company or as an alternative to operating cash flow as a measure of liquidity. EBIT is not necessarily comparable to similarly titled measures of other companies.

Cash flow is defined as cash flow from operations less capital expenditures. Cash flow is not a calculation based upon generally accepted accounting principles; however, the amounts included in the cash flow calculation are derived from amounts included in the consolidated financial statements of the Company. Cash flow should not be considered as an indication of liquidity of the company or as an alternative to cash flow from operations as a measure of liquidity. Cash flow is not necessarily comparable to similarly titled measures of other companies.