GOODWILL (Details) - USD ($) $ in Millions		3 Months Ended	12 Months Ended
	Aug. 31, 2017	Sep. 30, 2015	Sep. 30, 2017		Sep. 30, 2016		Sep. 30, 2015
Goodwill [Roll Forward]
Goodwill		$ 417					$ 417
Accumulated impairment losses		(15)					(15)
Goodwill, beginning balance			$ 390	[1]	$ 402
Impairment		(15)	0		0		(15)
Foreign currency translation			5		(12)
Goodwill acquired from acquisition			19
Goodwill, ending balance		402	414	[1]	390	[1]	402
Commercial Truck & Industrial
Goodwill [Roll Forward]
Goodwill		254					254
Accumulated impairment losses		(15)					(15)
Goodwill, beginning balance			230		239
Impairment			0		0
Foreign currency translation			3		(9)
Goodwill acquired from acquisition			19
Goodwill, ending balance		239	252		230		239
Aftermarket & Trailer
Goodwill [Roll Forward]
Goodwill		163					163
Accumulated impairment losses		0					0
Goodwill, beginning balance			160		163
Impairment			0		0
Foreign currency translation			2		(3)
Goodwill acquired from acquisition			0
Goodwill, ending balance		$ 163	$ 162		$ 160		$ 163
Fabco Holdings, Inc.
Goodwill [Line Items]
Purchase price	$ 34
Goodwill [Roll Forward]
Goodwill, ending balance	$ 19

[1] As of September 30, 2017, Assets and Liabilities held for sale were: (i) $1 million Cash and cash equivalents; (ii) $13 million Receivables, trade and other, net; (iii) $2 million Inventories; (iv) $3 million Net property; (v) $1 million Goodwill; (vi) $1 million Other assets; (vii) $12 million Accounts and notes payable; and (viii) $2 million Noncontrolling interests. As of September 30, 2016, Assets and Liabilities held for sale were: (i) $1 million Cash and cash equivalents; (ii) $8 million Receivables, trade and other, net; (iii) $1 million Inventories; (iv) $6 million Net property; (v) $5 million Accounts and notes payable; and (vi) $3 million Noncontrolling interests.