If you are talking about the turbo oil supply line that is mounted using a banjo fitting to the block inboard inboard of the oil filter and the tube has split or the banjo fitting is split, then REPLACE the oil line. If you are talking about the turbo oil return line then replace it too.

It might be prudent to replace both the supply tube and return tube while you are in there.

When you order the parts, make sure the guys KNOW which Turbo you have BEFORE they order it, make a point of making them show you what they are ordering for you. I had an episode of "ok dude, you're all set, the tube is on order" and of course it was the wrong one. Typical. Make sure the seal comes out of the return tube - you may need to get it out by sticking your finger in the recess where the tube sits in to get the seal out (it's more like a thick rubber O ring). I would assume you have either a Garret Turbo or a Mitsubishi Turbo. They are different and require different parts. TRUST ME.

If it's the oil supply line (banjo) it's easier than lining up the return tube when you are ready to do it. Don't tighten it up to the block, leave it loose enough to tighten up the seal at the supply line on top of the turbo and replace that gasket while you are at it too. It's worth the 4.00 for the gasket.

I just did mine two weeks ago, literally. If you have oil leaks and you are going to be in there, replace them so you won't have to screw with it for a long long time.

Another word to the wise. Make damn sure you know who you are ordering from. If you wind up with and aftermarket supply or return line, you may run into a MAJOR hassle when you are reistalling the Turbo parts. I was under there veryt recently and it sort of suck, no, it REALLY sucks !!
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Rich George