Federal Reserve Board Chair Janet Yellen
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That sound you hear is the Federal Reserve backing up a multi-trillion-dollar truck.

The Fed is getting ready to start unloading a large portion of its balance sheet, bringing an end to nearly a decade of unprecedented action to prop up the U.S. economy after the worst financial collapse in generations.

The central bank bought up Treasury bonds and mortgage-backed securities to push down long-term interest rates as tonic for the ailing economy. Now, the Fed is ready to shrink its $4.5 trillion in bond holdings.

The unprecedented reduction should begin this fall and could ultimately impact your own bottom line.

Here’s what you need to know.

Why is the Fed shedding bonds?

The economy has come a long way since the financial crisis and Great Recession: Employers are hiring, stocks are on fire and home prices are surging. But trouble spots remain — especially low inflation. So why are Fed chief Janet Yellen and her team contemplating anything that may hold back the economy?

They feel it’s time.

“The whole concept is to return to some type of ‘normalization,’ whatever that means,” says Joe Heider, founder of Cirrus Wealth Management in Cleveland.

The Fed has been raising a key short-term interest rate over the past 18 months. The central bank now wants to let bonds roll off its huge portfolio to help return long-term rates to a more historically “normal” level.

One main reason: Fed policymakers want some levers in case the U.S. falls into another recession. If interest rates are close to zero and the Fed’s bond holdings are already massive, the central bank may be rendered impotent the next time the economy needs help.

What does it mean for you?

The Fed’s plan is to start unwinding its balance sheet slowly, by casting off $10 billion a month – comprising $6 billion of government debt and $4 billion of mortgage-back securities – before eventually ramping up to $50 billion per month.

It’s that ramping up that could have some impact on your life. Here’s advice on how to protect yourself from three things you might see.

1.    Rising mortgage rates

The recent homebuying craze has been aided by ultra-low mortgage rates, which are tied to the yields on 10-year Treasury bonds. Right now, the more limited supply of government debt – courtesy of the Fed’s bond-buying — has pushed up bond prices and lowered yields. (Prices and yields are inversely related.)

When the Fed starts letting go of hundreds of billions of longer-term Treasuries, expect those yields to rise, in turn pushing up the cost of financing a home. If you’re thinking about buying a home or refinancing your existing mortgage, lock in a great rate when you spot one.

2.    Financial turbulence

Stock market volatility has has been noteworthy in recent months – because there’s been so little of it. Stocks have mainly been moving in one direction: up.

Investors should brace themselves for choppier days of both big gains and big losses as financial markets digest the Fed’s bond-trimming. Keep some money in certificates of deposit and other safer investments. Savers, meanwhile, should benefit from a higher interest rate environment.

3.    Lower economic growth

The current recovery is the third-longest expansion in U.S. history, lasting nearly 100 months, according to Goldman Sachs. That was made possible, in part, by historically easy monetary policy. Now that the Fed is moving in the opposite direction, albeit deliberately, it stands to reason that the current business cycle may finally meet its end — with a recession.

The uncertainty makes it very important that you build up your emergency fund.