Exhibit 99.C

Exhibit C

JOINT FILING AGREEMENT

In accordance with Rule 13d-l(k) under the Securities Exchange Act of 1934, as amended, the persons named below agree to the joint filing on behalf of each of them of a statement on Schedule 13D (including amendments thereto) with respect to the common stock, $10.00 par value, of SPX Corporation and further agree that this Joint Filing Agreement be included as an Exhibit to such joint filing.  In evidence thereof, the undersigned hereby execute this Agreement this 15th day of November, 2004.

RELATIONAL INVESTORS, L.P.

RELATIONAL FUND PARTNERS, L.P.

RELATIONAL COAST PARTNERS, L.P.

RELATIONAL PARTNERS, L.P.

RH FUND 1, L.P.

RH FUND 2, L.P.

RH FUND 4, L.P.

RH FUND 6, L.P.

RH FUND 7, L.P.

RELATIONAL INVESTORS III, L.P.

RELATIONAL INVESTORS VIII, L.P.

RELATIONAL INVESTORS X, L.P.

RELATIONAL INVESTORS XI, L.P.

RELATIONAL INVESTORS XII, L.P.

By:	RELATIONAL INVESTORS, LLC
	as general partner to each, except as the sole managing member of the general partners of Relational Investors III, L.P. and Relational Investors X, L.P.
		By:	/s/ Ralph V. Whitworth
			Ralph V. Whitworth, Principal
RELATIONAL INVESTORS, LLC
		By:	/s/ Ralph V. Whitworth
			Ralph V. Whitworth, Principal
			/s/ Ralph V. Whitworth
			Ralph V. Whitworth
			/s/ David H. Batchelder
			David H. Batchelder
			/s/ Joel L. Reed
			Joel L. Reed
			/s/ James J. Zehentbauer
			James J. Zehentbauer