There is never a wrong time to invest in mutual funds for retirement. So, if you're still looking for the best mutual funds, the Zacks Mutual Fund Rank can be a great guide.

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.

DFA US Large Cap Growth Institutional (DUSLX Quick QuoteDUSLX - Free Report) : 0.18% expense ratio and 0.15% management fee. DUSLX is a Large Cap Growth option; these mutual funds purchase stakes in numerous large U.S. companies that are expected to develop and grow at a faster rate than other large-cap stocks. With annual returns of 12.19% over the last five years, this fund is a winner.

Oppenheimer Gold & Special Mineral Y (OGMYX Quick QuoteOGMYX - Free Report) : 0.82% expense ratio and 0.58% management fee. OGMYX is classified as a Sector - Precious Metal fund, and these mutual funds invest in stocks with a focus on the mining and production of precious metals like gold, silver, platinum, and palladium. With yearly returns of 11.24% over the last five years, OGMYX is an effectively diversified fund with a long reputation of solidly positive performance.

Putnam Large Cap Value Y (PEIYX Quick QuotePEIYX - Free Report) is an attractive large-cap allocation. PEIYX is a Large Cap Value mutual fund, which invests in stocks with a market cap of $10 billion of more, but whose share prices do not reflect their intrinsic value. PEIYX has an expense ratio of 0.64%, management fee of 0.47%, and annual returns of 10.27% 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.