* Transport protests worsen chaos in capital Santiago
* Week of protests has led to deaths, arrests, destruction
* President Pinera seeking to placate demonstrators
* Chile unrest adds to wave of street protests round world (Adds Pinera quote, context, latest damage, deaths and protest details)
SANTIAGO, Oct 25 (Reuters) - Chilean truck and taxi drivers brought gridlock to the capital's highways on Friday in a protest against high road tolls that added to a week of rowdy demonstrations over social inequality.
Protests that started over a hike in public transport fares boiled into riots, arson and looting that have killed at least 17 people, injured hundreds, brought more than 7,000 arrests and caused more than $1.4 billion of losses to Chilean businesses.
On Friday morning, trucks, cars and taxis slowed to a crawl on major roads, honking horns, waving Chilean flags and bearing signs of protest. "No more tolls! Enough with the abuse!" read bright yellow-and-red signs plastered to the front of vehicles.
Chile's unrest is the latest in a flare-up of protests in South America and round the world - from Beirut to Barcelona - each with local triggers but also sharing underlying anger at social disparities and ruling elites.
Chile's two-term President Sebastian Pinera trounced the opposition in the most recent 2017 election, dealing the center-left ruling coalition its biggest loss since the end of Augusto's Pinochet's dictatorship in 1990.
But now many protest placards call for his exit.
The protests are still without a leader, spokesperson or political party. Students and unions organizing on social media touted plans to launch "The Largest March in Chile" on Friday afternoon, with rallies expected to paralyze major cities.
"These protests were necessary," said fruit vendor Sergio Perez. "But they've made everything difficult, especially getting around."
The streets of downtown Santiago were littered with trash and broken glass and reeked of tear gas early on Friday from the latest marches and clashes. Many shops and schools remained closed.
Vandals set fire to underground transport trains and stops in Chile's capital last weekend, sowing nearly $400 million in damage and hobbling public transportation. Chile's military has since taken over security in Santiago, a city of 6 million now under a state of emergency with night-time curfews.
"THIS MUST STOP"
Many bus drivers in Santiago also staged a walk-off on Friday after one of their number was shot.
"I used to take one bus to get to work, now I have to take four. This must stop," said Julio Herrera, 71, as he waited in a long line at a street corner for what few buses remained.
While much of wealthy east Santiago remains calm under evening lockdown, the poorer flank of the city has seen widespread vandalism and looting.
Pinera, a billionaire businessman, told the nation on Thursday he had heard "loud and clear" the demands of Chileans.
He has sent lawmakers legislation to overturn a recent hike in electricity rates, and called for reforms to guarantee a minimum wage of $480 a month and introduce state medical insurance for catastrophes.
Seated with a group of elderly Chileans over lunch on Friday, Pinera put finishing touches on a bill to hike minimum pensions by 20%."We must approve these projects with the urgency that Chileans demand," Pinera said.
The biggest rallies, according to interior ministry figures, took place on Wednesday, with 424,050 people rallying nationwide. By Thursday, protests simmered to 102,680 people.
An online poll conducted by local company Activa Research of 2,090 people between Oct. 22-23 found 83% of respondents said they supported the goals of the demonstrators, but 72.5% opposed violence as a method of protest.
The principal causes of the protests were low salaries, utility prices, pensions and economic inequality, the poll said.
U.N. human rights boss Michelle Bachelet, a former president of Chile, said she would send a mission to her homeland to investigate allegations of rights violations by security forces. The Chilean government said it would welcome a U.N. delegation, along with representatives of global NGO Human Rights Watch.
(Reporting by Dave Sherwood; Additional reporting by Natalia Ramos, Aislinn Laing and Fabian Cambero; Writing by Dave Sherwood; Editing by Andrew Cawthorne)