Michael Birch was left in a critical but stable condition after the crash in which 23 people were injured.
The bus and lorry collided on Wednesday near Colchester, with the steam engine falling into the front of the bus.
Friends hope to raise Â£2,000 to help Mr Birch and his family. They described him as a "really genuine guy".
Of the 23 injured in the accident in East Mersea, seven were seriously hurt including the 44-year-old bus driver from Colchester.
A 51-year-old Great Yarmouth man arrested after the collision on suspicion of causing serious injury by dangerous driving has been released on police bail.
Cab driver Dan Hammett, 24, and bus driver Laura Bearder, 37, helped set up the fundraising page for Mr Birch.
Mr Hammett, who has known Mr Birch for several years, said: "One thing you don't want is financial pressure when you're concerned for your loved ones.
"Hopefully if this raises a few hundred pounds for him and his family, it will be a great help, even if it's train tickets to see him in hospital."
By Saturday morning, more than 40 people had pledged a total of almost Â£600.
Ms Bearder described Mr Birch as a "really loyal, dependable guy."
She said as a fellow bus driver, the news of the crash had rocked her and her colleagues.
"Driving around yesterday, you could tell by the looks on the faces of the other drivers - it's so sad, he's one of ours," she said.
First Essex managing director Alex Jones said the firm had received countless messages of support for its driver from colleagues and customers, and it was supporting his family.
"Our thoughts are also with those customers that were injured as a result of the incident," he said.
A fundraising page has been set up for a bus driver seriously injured in a crash that saw a steam engine fall off a lorry into his bus.