Chris Pizzello/AP

Frank Dileo's final days were reportedly darkened by feuds with the late Jackson's co-executors.

Frank Dileo rests in peace - though we hear he was pretty agitated about Michael Jackson's estate before he died.

As the music world mourned the loss of Jackson's old-school cigar-chomping manager, who died on Wednesday, friends of Dileo tell us that his last healthy days were darkened by a growing disenchantment with the late pop star's co-executors.

One source says that early this year, Dileo even fired off an angry email to one of those executors, entertainment attorney John Branca, to complain about co-executor John McClain.

"He told Branca that he was very disappointed," says the friend who adds: "They were cutting Frank's power" and money he received as a consultant to Jackson's estate.

"He felt he wasn't getting his fair share financially and that McClain was undermining him," says the source.

Dileo, who managed the King of Pop from his "Thriller" years in the mid-'80s until the end of the decade and reunited with him shortly before Jackson's death in 2009, was particularly incensed with McClain's reaction to new Jackson tracks that were released posthumously on the album "Michael" last year.

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McClain, who had briefly managed Jackson in the early '90s, was among a Greek chorus that claimed an impostor was on the tapes. (Forensic experts concluded they were legit.)

Dileo told us he had brought the songs to the attention of Jackson's record label, Sony, and in his email to Branca, the source says he accused McClain of spreading "negative spin" about him and the record.

According to the source, Dileo also accused McClain of "standing in the way of the marketing plan" for "Michael" by "not letting anyone hear the record."

In January, Dileo told us he was writing a memoir in which he would set the record straight about Jackson and the controversy behind "Michael." Shortly after our story ran, the source says the estate paid Dileo "a bonus."

Now it's unclear if the book will see the light of day. After undergoing heart surgery in March, Dileo experienced complications and never recovered. He was 64.

Calls to McClain and Branca were not returned by deadline. In response to our questions, a spokesman for Jackson's estate wrote: We believe it is appropriate to limit our comments" to "those we have already expressed ... We will always be grateful for Frank's contributions to Michael Jackson's career and to the estate, and our hearts go out to the Dileo family."

Contact Gatecrasher:
Frank DiGiacomo: fdigiacomo@nydailynews.com
Carson Griffith: cgriffith@nydailynews.com
Adam Caparell: acaparell@nydailynews.com

Read more: http://www.nydailynews.com/gossip/2011/08/25/2011-08-25_frank_dileo_michael_jacksons_former_manager_fed_up_with_pop_stars_estate_before_.html#ixzz1W9RwD9mC