I concur with Mr. Justice Carr’s opinion so far as it relates to the validity of the order of August 6, 1957. However, I must respectfully dissent therefrom so far as it relates to the order of August 26, 1957, exempting United Parcel Service from the provisions of the minimum rate schedule of 1950.
In the trial court’s opinion can be found the following statement of facts concerning the August 26, 1957, order:
“In 1950 the commission issued an order (D 3476, Supp 6), setting minimum rates for contract and *607common carriers of property, and exempting therefrom certain territory, certain commodities and certain carriers.
“On August 15, 1957, and after the issuance of the opinion and order of August 6, 1957, United Parcel filed a petition seeking an exemption from the above-mentioned order. On August 26, 1957, the commission caused the petition to be published in its information bulletin, and by order dated the same day, granted said petition. On August 28, 1957, the plaintiffs served written notice on the commission, requesting that a hearing be held and no action be taken without providing plaintiffs an opportunity to be heard. (Emphasis added.)
“On September 5, 1957, the plaintiffs, without a hearing thereon having been granted them, were served with the order exempting United Parcel from the minimum rate order. On September 19, 1957, the original plaintiffs filed an amended bill of complaint herein, appealing from the exemption order.”
Article 5, § 18, of the motor vehicle carrier act, CL 1948, § 479.18 (Stat Ann § 22.583), provides in part:
“The commission may upon application of any person or any motor carrier, or upon its own motion, and upon at least 10 days’ notice to the parties affected thereby, for good cause, and after an opportunity to be heard, revoke, suspend, alter, amend or modify any and all of its findings or orders; but no certificate or permit shall be amended, altered, modified, revoked, suspended, or impaired, except only after like notice and opportunity to be heard and upon clear proof of good, just, and sufficient cause.”
While noting that the commission’s order of August 26, 1957, was written in terms of an amendment of the minimum rate order, the trial court concluded :
“That amendment so-called does not change the substance of the order of August 26th in any respect *608whatever, and in our opinion is not such an amendment of an order as comes within the provisions of CL 1948, §479.18 (Stat Ann §22.583). Had the amendment been one of substance, then we think plaintiffs’ position would have been well taken, but it is obviously not such an amendment.”
Reliance was placed by the trial court on language contained in this Court’s opinion in In re Application of Joe Brown & Sons, 273 Mich 652, 656, where it was held that a change of the substance of a former order could only be done in strict compliance with section 18 of the act, above quoted. In the case at bar the trial court concluded that such language indicated that compliance with article 5, § 18, was not required if the change is not one of substance.
I cannot agree that exemption of a carrier’s operations previously subject to the minimum rate order is not a change in substance. The exempted carrier would not contend (and defendant United Parcel Service of Detroit, Inc., does not argue before this Court, except by reference to the trial court’s opinion) that the order of August 26, 1957, was not a change of substance as it related to it. The change authorized by the exemption order permitted defendant carrier to file a rate schedule, and to charge rates, below the rates permitted to be charged by its competitors. On the other hand, it cannot be said that the August 26,1957, order was not a change in substance affecting defendant carrier’s competitors, including plaintiffs. The change authorized by the exemption order permitted defendant carrier to assume a competitive advantage over them solely because it freed defendant carrier from the minimum rate schedule which still bound them. When an administrative agency undertakes to establish minimum rates for a regulated industry, it must *609do so uniformly, unless good cause is shown for doing otherwise.
This principle was recognized by the commission when it promulgated its minimum rate order in the following statement of purposes:
“We find that an order prescribing the rates and charges to be assessed and observed, and classifications and the rules and regulations to govern all types of motor carriers (except as hereinaftér provided) is both necessary and desirable in the public interest to remove unjust and unreasonable rates, charges, classifications, rules and regulations, and practices, to enable said carriers to provide safe and adequate service, facilities and equipment for the transportation of property in intrastate commerce, to foster sound economic conditions in the transportation of property by said carriers, and to promote adequate, economic, and efficient service by motor carriers within this State at reasonable rates without unjust discrimination, undue preference or advantage, or unfair or destructive competitive practices.”
Article 5, § 18, of the act permits amendment of prior orders, but only for good cause, upon notice to affected parties and after an opportunity for hearing. In the absence of the prescribed notice and hearing, the order of August 26, 1957, is invalid.
Defendants contend that other exemption orders have been issued by the commission without hearing. Testimony was offered relating to only 4 or 5 such orders issued without hearing, but in none was there shown to be an absence of notice. Furthermore, the supervisor of the commission’s rates and tariffs sec,tion testified that the general policy of the commission was to hold hearings before issuing an order modifying the minimum rate order whenever there *610was any objection made to a petition for exemption. The evidence discloses no valid reason for the commission’s failure to comply with the plaintiffs’ request for a hearing as the statute requires.
I would affirm the decree of the trial court as it relates to the order of August 6, 1957, reverse the decree as it relates to the order of August 26, 1957, and remand for the entry of a decree in compliance herewith. I would award no costs, none of the parties having fully prevailed.
Smith, Black, and Edwards, JJ., concurred with Souris, J. Dethmers, C. J., and Kavanagh, J., did not sit.