* Sees savings of $440 mln from Centex deal, up 25 pct

* Q3 loss $1.15 a share; Street view loss $0.69

* Gross margins higher

* Shares jump 5 percent (Recasts first paragraph, updates stock move, adds background)

NEW YORK, Nov 4 (Reuters) - Pulte Homes Inc (PHM.N: Quote, Profile, Research) said its recent acquisition of a rival homebuilder will boost its financial health more than previously estimated, sending its shares up 5 percent despite a quarterly loss and ongoing challenges in the battered industry.

Pulte, which after buying Centex Corp has operations in 29 states, said on Wednesday its new target for efficiencies and savings from is $440 million, up 25 percent from its prior estimate.

The upward revision to the merger's benefits as well as higher-than-expected gross margins and lower-than-expected impairments make the third-quarter results "a positive for the company," J.P. Morgan analyst Michael Rehaut wrote in a note to clients.

Pulte shares were up 47 cents, or 5.1 percent, to $9.70 in afternoon trading on the New York Stock Exchange.

Pulte's third-quarter gross margins of 13.1 percent, excluding interest, merger costs and impairments, were up from the second quarter and were solidly higher than Rehaut's 11.2 percent estimate.