GOODWILL (Details) $ in Millions	3 Months Ended	12 Months Ended
Sep. 30, 2015 USD ($)	Sep. 30, 2015 USD ($) segment unit	Sep. 30, 2014 USD ($)	Sep. 30, 2013 USD ($)
Goodwill [Line Items]
Number of operating segments \| segment		3
Goodwill [Roll Forward]
Goodwill, beginning balance		$ 431	$ 434
Impairment	$ (15)	(15)	0	$ 0
Foreign currency translation		(14)	(3)
Goodwill, ending balance	402	$ 402	431	434
Commercial Truck & Industrial
Goodwill [Line Items]
Number of reporting units \| unit		3
Goodwill [Roll Forward]
Goodwill, beginning balance		$ 261	262
Impairment		(15)
Foreign currency translation		(7)	(1)
Goodwill, ending balance	239	$ 239	261	262
Aftermarket & Trailer
Goodwill [Line Items]
Number of operating segments \| unit		1
Goodwill [Roll Forward]
Goodwill, beginning balance		$ 170	172
Impairment		0
Foreign currency translation		(7)	(2)
Goodwill, ending balance	$ 163	$ 163	$ 170	$ 172

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of increase (decrease) from foreign currency translation adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Number of reporting units tested for impairment of goodwill. A reporting unit is an operating segment or one level below an operating segment.

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