Truck Q: drive shaft seal

My wife is looking at used trucks, and has found one online that she is interested in. The dealership is a bit far away, so before we head on out there, we’re trying to learn as much in advance as possible. Along with photos, the dealer has provided a written list of defects, all of which are cosmetic. Except, perhaps, for this:
[li]There is some minor seepage from the front right axle drive shaft seal.[/li][/ul]
Obviously, we’ll be taking any prospective purchase to a local mechanic for a full inspection, but I’d like to understand this a bit more before it even gets to that.

Is this a potentially serious issue? If so, how serious (in time/money)? If not, why wouldn’t the dealer just go ahead and repair it now? Does it matter how “minor” the seepage really is?

If it matters, the truck is a 2001 Tahoe, with ~58k miles.

Thanks in advance.

I assume the vehicle is 4WD. I would try to get the dealer to replace the seal. As a last resort, the very last, if it’s otherwise in good shape and I wanted that particular vehicle I’d tell the dealer to fix it and add the cost to the purchase parice. That way, your payments over 36 months go up a little and you are spared what will be a constant annoyance, at least, because the seepage isn’t going to get better.

It’s really not that big of a deal, which really makes me wonder why the dealer didn’t just replace the seal instead of listing it as a defect. I suspect that the dealer knows something else is amiss and is covering their butt legally by letting you know the seal leaks.