* Prices retreat further from 18-month highs
* Levels could hold below $85; back in range
* Crude down despite dollar weaker, equities' gain
* Coming up: Weekly U.S. Commitment of Traders report (Recasts; dateline from LONDON)
By Gene Ramos
NEW YORK, April 9 (Reuters) - Oil prices fell below $85 a barrel on Friday, retreating further from 18-month highs, as bloated inventories stoked concerns about weak demand and technical signals sparked a selloff.
The downturn erased early gains fueled by economic optimism and a weaker dollar.
The stark effects of weak fundamentals in the United States, the world's largest oil consumer -- where crude inventories have risen for the past 10 weeks -- overrode guidance from financial markets, analysts said.
Front-month U.S. crude <CLc1> fell 93 cents to $84.46 a barrel by 1:40 p.m. EDT (1740 GMT), after earlier hitting a session high of $86.37. In London, ICE Brent crude <LCOc1> was 50 cents lower at $84.31, after climbing more than $1 to $85.94 earlier in the session.
"Fundamentals are forcing crude to disconnect from financials," said Jim Ritterbusch, president of Ritterbusch & Associates in Galena, Illinois.
For the moment, the dollar is weaker against the euro while Wall Street rose on hopes that aid could finally be cobbled up for beleaguered Greece. [
] [ ]The euro rose against the dollar as deputy finance ministers and central bankers in the euro zone decided that any emergency loans to Greece would be made on terms almost identical to standard International Monetary Fund bailouts, if Athens needed them. [
]That eased earlier worries as Fitch Ratings cut Greece's credit ratings by two notches and signaled further downgrades are possible, citing intensifying fiscal challenges in the debt-ridden country. [
]Usually, a dip in the dollar makes commodities more attractive to investors seeking less risky assets.
Early in the week, oil prices broke above the $65 to $85 range, where they have traded since August, to touch an 18-month high of $87.09 on Tuesday.
But government data on Wednesday put the breaks on the six-day rally as U.S. crude inventories reached their highest level in almost 10 months, an indication supply is still outpacing demand. [
]"The past week's rally moved to a point where it's gotten ahead of itself," said Tom Pawlicki, an analyst at MF Global Research in Chicago.
Other analysts attributed Friday's drop to a technical reversal.
"The drop is being mostly fueled by technical selling after a top at around $87. We are currently likely to come back to the recent range between $80 and $83," said Eugen Weinberg, head of Commodities Research at Commerzbank in Frankfurt.
Looking ahead, traders were expected to keep a close eye on the yuan-dollar relationship. China, the world's second-largest oil consumer, has pegged the yuan near 6.83 per dollar since mid-2008 to help its exporters weather the global crisis.
But this has drawn increasing complaints from Washington that the yuan is seriously undervalued, handing Chinese firms an unfair trading advantage and effectively exporting unemployment.
Some think a revaluation would boost China's oil demand in the short term as it will make dollar-denominated crude cheaper for Chinese buyers. (Additional reporting by Robert Gibbons in New York, Emma Farge in New York and Alejandro Barbajosa in Singapore; Editing by Walter Bagley)