Sirius ( SIRI) says its radios will be standard equipment on four models of Mitsubishi's 2007 car line and in all the 2008 models.

The deal, initially struck last year with the struggling automaker, was updated Monday by naming the 2007 models to feature factory-installed radios. According to Sirius, the radios will be available in the Galant Ralliart and Endeavor SE cars, along with the Raider LS and DuroCross double-cab pickup trucks. The radios will be an option on other levels of the 2007 Galant, Endeavor and Raider and the Outlander.

"Mitsubishi has been a great partner in the growth of Sirius, and we are very pleased that they have decided to expand the number of vehicle lines offering Sirius," CEO Mel Karmazin said in a press release.

Sirius and Washington, D.C.-based rival XM ( XMSR) have nearly split the carmakers down the middle, with each of the major players aligning with one or the other broadcaster. XM's largest automaking partner, GM ( GM), is expected to build 1.55 million cars and trucks this year with factory-installed XM radios.

Both companies are negotiating follow-on deals with the carmakers.

Sirius is expected to report second-quarter earnings before the market opens Tuesday. Analysts are looking for a net loss of 15 cents a share on revenue of $147 million in the second quarter.

The New York pay-radio shop already announced it signed on 600,460 net new users, pushing its subscriber roll to 4.7 million. XM said last week that its user total is now more than 7 million, though the company disappointed investors by trimming its year-end subscriber guidance for the second time.

Sirius shares rose 7 cents to $4.21 in premarket trading Monday.