Shares of Genuine Parts (GPC -2.12%) tumbled 3.3% through 11 a.m. ET Tuesday despite beating analyst targets for sales and earnings this morning.

Heading into its fourth-quarter 2024 report, Wall Street thought Genuine Parts would earn $1.55 per share, adjusted for one-time items, on sales of just over $5.7 billion. In fact, the auto and industrial parts supplier earned $1.61 per share, and its sales approached $5.8 billion.

Fourth quarter earnings

Not all the news was good. Quarterly sales beat expectations but still rose only 3.3% year over year. Worse, an inventory write-down shrank gross profit margins 50 basis points to 35.9%. And while Genuine Parts reported $1.61 in adjusted earnings per share (EPS), its actual earnings as calculated according to generally accepted accounting principles (GAAP) were only $0.96 per share, less than half what the company earned in the year-ago quarter.

Management attributed the decline to "costs associated with the company's global restructuring initiative, the acquisition and integration of independent stores and [the aforementioned] charge to write down certain existing inventory."

For the full year, sales grew only 1.7% to $23.5 billion, and earnings declined 31% to $6.47 per share.

Genuine Parts' big earnings warning

And here's the worst news: Turning to guidance, management said sales will grow only 2% to 4% in the coming year, and its adjusted EPS will range from only $7.75 to $8.25, all of which is below analysts' forecast earnings of $8.29.

GAAP profits will probably be lower again, at $6.95 to $7.45 per share. And on top of all that, management anticipates taking a big charge to earnings when its U.S. pension plan termination settles in late 2025 or in early 2026.

Management isn't including this charge in its 2025 forecast because it might not happen in 2025 at all. But make no mistake: Whether it happens in 2025 or in 2026, diluted EPS will be affected.

That's an earnings warning, folks. Pay attention to it.