* Canadian dollar weakens 0.2% against the greenback

* Trade surplus hits a four-year high

* U.S. crude oil futures drop 5.7%

* Bond yields fall across the curve

By Fergal Smith

TORONTO, Aug 4 (Reuters) - The Canadian dollar weakened

against its U.S. counterpart on Tuesday as oil prices fell and

despite data that showed Canada posting a fourth-straight month

of trade surpluses.

The loonie was trading 0.2% lower at 1.4070 per U.S.

dollar, or 71.07 U.S. cents, after touching its weakest intraday

level since last Wednesday at 1.4076.

* Canada's trade surplus hit a four-year high of C$3.86

billion ($2.75 billion) in June, when a weaker Canadian dollar

helped inflate the value of exports and imports. Analysts had

forecast a surplus of C$3 billion.

* "June's data confirm that a further rebound in export

volumes from the lows seen in 2025 appears to have been a large

driver of the strength in GDP signalled for Q2," Andrew

Grantham, senior economist at CIBC Capital Markets, said in a

note. "However, with the threat of new tariffs looming, this

surge in exports could easily slow or stall ahead."

* Preliminary data has pointed to Canada's economy growing

by 3.4% in the second quarter on an annualized basis.

* The U.S. announced new tariffs on nearly $20 billion worth

of Canadian goods last month.

* Separate data on Tuesday showed that Canada's

manufacturing sector expanded in July at the fastest pace in

more than four years as rising domestic activity boosted

production and new orders, but weak international demand raised

doubt over the sustainability of the increase.

* The price of oil, one of Canada's major exports,

fell 5.7% to $75.80 a barrel after comments by Qatari and U.S.

officials raised hopes for a diplomatic resolution to the Iran

war that could improve oil flows through the Strait of Hormuz.

* Canadian bond yields moved lower across the curve as the

market reopened following Monday's civic day holiday. The

10-year was down 10 basis points at 3.565%, pulling

back from a two-month high on Friday.