Investing in mutual funds for retirement is never too late. And the Zacks Mutual Fund Rank can be an excellent tool for investors looking to invest in the best funds.

The easiest way to judge a mutual fund's quality over time is by analyzing its performance, diversification, and fees. Using the Zacks Mutual Fund Rank of over 19,000 mutual funds, we've identified three outstanding mutual funds that are ideally suited to help long-term investors pursue and achieve their retirement investing goals.

Let's break down some of the mutual funds with the top Zacks Mutual Fund Rank and the lowest fees.

DFA US Core Equity 2 I

(DFQTX Quick QuoteDFQTX - Free Report) has a 0.19% expense ratio and 0.16% management fee. DFQTX is classified as a Large Cap Blend fund. More often than not, Large Cap Blend mutual funds invest in companies with a market cap of over $10 billion. Buying stakes in bigger companies offer these funds more stability, and are well-suited for investors with a "buy and hold" mindset. With yearly returns of 13.32% over the last five years, this fund clearly wins.

Goldman Sachs Enhnc Core Eq R6

(GFCUX Quick QuoteGFCUX - Free Report) is a stand out amongst its peers. GFCUX is a Large Cap Growth mutual fund, and these funds invest in many large U.S. firms that are projected to grow at a faster rate than their large-cap peers. With five-year annualized performance of 15%, expense ratio of 0.56% and management fee of 0.55%, this diversified fund is an attractive buy with a strong history of performance.

Principal Mid Cap R5

(PMBPX Quick QuotePMBPX - Free Report) . Expense ratio: 0.84%. Management fee: 0.58%. Five year annual return: 11.27%. PMBPX is a Mid Cap Growth mutual fund. These mutual funds choose companies with a stock market valuation between $2 billion and $10 billion.

There you have it. If your financial advisor had you put your money into any of our top-ranked funds, then they've got you covered. If not, you may need to talk.