While Fools should generally take the opinion of Wall Street with a grain of salt, it's not a bad idea to take a closer look at particularly stock-shaking analyst upgrades and downgrades -- just in case their reasoning behind the call makes sense.

What: Shares of J.B. Hunt Transport Services (JBHT 0.05%) closed up 2.6% on Friday after Bank of America upgraded the transportation services company from neutral to buy.

So what: Along with the upgrade, analyst Ken Hoexter reiterated his price target of $81, representing about 9% worth of upside to where the stock sits now. J.B. Hunt shares have been sluggish in recent months on concerns over rising costs, but Hoexter believes it provides investors with a decent entry point given the company's long-term growth prospects.

Now what: B of A expects J.B. Hunt to earn $3.60 per share in 2014. "In our view JBHT is a solid secular growth story given its core Intermodal business improvement," said B of A. "While we recognize near-term weakness heading into earnings, primarily driven by higher costs in its non-core segments Dedicated and Truck, we believe this to be a temporary overhang on the stock." Given J.B. Hunt's still-hefty debt load and seemingly lofty forward P/E of 27, however, I'd expect the stock to remain under pressure for much longer than B of A believes.