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 best way to shortlist great mutual funds is to ensure solid performance, diversification, and low fees. Some are better than others, but utilizing the Zacks Mutual Fund Rank, we have identified three mutual funds that could be solid additions to one's retirement portfolio.

Here are the funds that have achieved the Zacks Mutual Fund Rank #1 (Strong Buy) and have low fees.

Van Eck International Investors Gold I (INIIX): 1% expense ratio and 0.72% management fee. INIIX is a Sector - Precious Metal mutual fund, typically investing in companies that are involved in the mining and production of precious metals like gold, silver, platinum, and palladium. INIIX has achieved five-year annual returns of an astounding 24.26%.

Invesco Main Street R (OMGNX): 1.06% expense ratio and 0.44% management fee. OMGNX 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. OMGNX, with annual returns of 12.34% over the last five years, is a well-diversified fund with a long track record of success.

American Funds New Economy F (ANFFX Quick QuoteANFFX - Free Report) is an attractive large-cap allocation. ANFFX is a Global - Equity mutual fund. These funds invest in large markets like the U.S., Europe, and Japan, and operate with very few geographical limitations ANFFX has an expense ratio of 0.78%, management fee of 0.37%, and annual returns of 11.38% over the past five years.

These examples highlight the fact that there are some astonishingly good mutual funds out there. If your advisor has you in the good ones, bravo! If not, you may need to have a talk.