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GM to Test Syntroleum Fuels

1 June 2000

GM to Test Syntroleum Fuels

    TULSA, Okla., June 1 Syntroleum Corporation
announced today the execution of a fuels testing agreement with General Motors
Corporation .  The agreement covers testing of synthetic fuels for
advance power train systems.
    "Because synthetic fuels could someday play a role in the US and Europe,
we are interested in better understanding their properties and advantages,"
stated Dr. James Spearot, Director of GM's Chemical & Environmental Sciences
Lab.  "The tests will be conducted as part of our power train development
program to further define the benefits of these fuels relative to our current
and future engine designs."
    "We are pleased to be have GM's expertise added to the growing number of
companies helping to establish the benefits of synthetic fuels in various
power train technologies," said Mark Agee, Syntroleum president and chief
operating officer.
    Syntroleum Corporation, which is headquartered in Tulsa, Oklahoma,
licenses its proprietary process for converting natural gas into synthetic oil
and transportation fuels. These ultra-clean fuels are more environmentally
friendly than conventional fuels because they are virtually free of sulfur,
aromatics and heavy metals.  The process is designed for application in plant
sizes ranging from 2,000 barrels per day to more than 100,000 barrels per day.
Current licensees include ARCO, Enron, Ivanhoe Energy, Kerr-Mcgee, Marathon,
Texaco, and Repsol-YPF.

    This document includes forward-looking statements as well as historical
information. Forward-looking statements include, but are not limited to,
statements relating to the testing, certification, characteristics and use of
synthetic fuels and alternative fuels, the Syntroleum Process and related
technologies and products, GTL plants based on the Syntroleum Process
(including the development of planned plants), the economic use of such plants
and the continued development of the Syntroleum Process. When used in this
document, the words "anticipate," "believe," "estimate," "expect," "intent,"
"may," "project," "plan" "should," and similar expressions are intended to be
among the statements that identify forward-looking statements. Although
Syntroleum believes that its expectations reflected in these forward-looking
statements are reasonable, such statements involve risks and uncertainties and
no assurance can be given that actual results will be consistent with these
forward-looking statements. Important factors that could cause actual results
to differ from these forward-looking statements include the potential that
commercial-scale GTL plants will not achieve the same results as those
demonstrated on a laboratory or pilot basis or that such plants will
experience technological and mechanical problems, the potential that
improvements to the Syntroleum Process currently under development may not be
successful, the impact on plant economics of operating conditions (including
energy prices), construction risks, risks associated with investments and
operations in foreign countries, the ability to implement corporate
strategies, competition, intellectual property risks, Syntroleum's ability to
obtain financing and other risks described in the company's filings with the
Securities and Exchange Commission.

    (R) "Syntroleum" is registered as a trademark and service mark in the U.S.
Patent and Trademark Office.