Lindsay Lohan -- Truck Driver Is A LIAR!!!

Lindsay Lohan is calling BS on the truck driver’s allegation of bribery ... and everything else he said about the aftermath of their accident is a flat out lie ... sources close to Lohan tell TMZ.

As TMZ previously reported, James -- the guy driving the 18-wheeler Lindsay crashed into on Friday -- told TMZ her people tried to offer him money to keep quiet. He also claimed Lindsay and her people took a mysterious bag out of her Porsche and told James not to mention it to police.

According to our sources, Lindsay says the whole tale is made up -- there was no bribe attempt and no bag removed the car.