What: Investors received some much needed relief Friday when shares of American Axle & Manufacturing Holdings (AXL 1.09%) soaring almost 20% during early Friday trading after the company posted a strong fourth-quarter. However, even with the 20% jump on Friday it's been a brutal year for the company's stock.

AXL Chart

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So what: Looking at American Axle's (AAM) fourth-quarter results, sales reached $958 million and the company recorded net income of $62.9 million. That equates to earnings per share of $0.81, which was ahead of consensus estimates of $0.69 per share. AAM's gross profit in the fourth-quarter jumped to nearly $160 million, much higher than the prior year's $111 million result with gross margins jumping from 11.8% to 16.7% during the same time frame. Its strong fourth-quarter helped the company end 2015 in style.

If you are a fan of historic results, AAM's full-year results will help you end your week on a good note: the company set record annual sales, record non-GM sales, and record gross profit during 2015. Certainly not a bad way to cap off a year.

Now what: Going forward there are a couple of things for investors to watch. First, keep an eye on the company's non-GM sales as it continues to focus on expanding and diversifying its business. While General Motors, in my opinion, is poised for strong global sales growth which will certainly benefit AAM, it's important for the company to expand its business relationships. Another metric to watch is the company's content-per-vehicle, which was $1,645 during the fourth-quarter, down slightly from the prior year's $1,667.

If the company can continue to grow its margins, increase its content-per-vehicle, and expand its business further beyond GM, this likely won't be the last day its stock price jumps double digits.