He also pleaded guilty to running an illegal money lending business (loan sharking) and ten counts of counterfeiting.
His son, Christopher Walker, was sentenced to 12 months imprisonment for kidnap and a concurrent nine month sentence for assault.
In May last year the father and son duo kidnapped a customer from the loan shark business who had fallen behind on repayments on a loan. The original loan was £800 but Walker added charges making it up to £2,000.
His interests rates ranged from 1,500 to 117,000 APR.
After assaulting their victim in the back of their vehicle Lee and Christopher Walker then drove to his family home and threatened his mother.
At a second location he was attacked with a machete and a baseball bat before being let go.
Consumer minister Ian McCartney welcomed the jail terms and congratulated the Birmingham loan shark team whose work led to the arrests.
"It takes a real parasite to prey on the most vulnerable in our communities and bully and intimidate them out of their hard-earned money," he said.
"I hope that this case gives hope to the thousands of people who live in fear of loan sharks. Today shows that people don't have to live in fear. If you can find the courage to come forward, we will back you up."
Councillor Neil Eustace, chair of Birmingham City Council's public protection committee, described the Walker case as one of the "most violent and shocking examples of illegal money lending".
"Today's sentence sends a clear message to loan sharks who would seek to exploit some of the most vulnerable people in our society that they will be caught and brought to justice," he added.
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