JOHANNESBURG, May 4 (Reuters) - The South African rand was flat in early trade on Monday ahead of the release of a local manufacturing purchasing managers' index (PMI) and vehicle sales data for April.

o At 0639 GMT the rand traded at 16.6075 against the dollar, broadly unchanged from its previous close.

o An Absa PMI survey is set to be released at 0900 GMT and will shed light on manufacturing conditions in Africa's most industrialised economy.

o South African manufacturing sentiment remained weak in March, with respondents expressing concern about the impact of the Iran war although business activity is yet to take a serious knock.

o Investors will then turn their focus to vehicle sales data due around 1200 GMT, which will give a snapshot of consumer demand for big-ticket items.

o Nedbank economists, in a research note, said they expect car sales to contract by 16% in April, largely reflecting more public holidays than in March and softer demand amid uncertainty over the war in Iran.

o "Higher fuel prices and a shifting interest rate outlook are likely to weigh on consumer confidence and, in turn, vehicle demand. Even so, the decline comes off a high base," said the note.

o South Africa's benchmark 2035 government bond was stronger in early deals, as the yield fell 3.5 basis points to 8.76%.

(Reporting by Sfundo Parakozov;Editing by Louise Heavens)