I think this is an aftermarket front driveshaft? I’m not sure what they look like as this is my first disco. It has long grease zerts on the u joints.

 

Yes, it's aftermarket driveshaft, what brand I am not sure, (but it's not GKN even though it says on it),

 

That looks like an OE LR Drive Shaft with greasable MOOG 344 U joints.

Not really the strongest U joint on the planet( OK for on road/DD). And not a fan of those long zerks. With the drive shaft/suspension fully articulated (like with a lifted truck) they tend to hit the drive shaft yokes (don't ask how I know this ).
Those zerks should also be in the opposite direction/phase of each other.

MOOG-344 - U-Joint made by MOOG

 

I agree it looks like an OEM front shaft that's been rebuilt. The lower half isn't painted bright blue on the splines so I'm going with rebuilt OEM unit.

 

Ok I’ll switch it out for the tom woods shaft I got. I’ll keep it around for a spare. Thanks everyone ��

 

That's a good call, especially with the new lift.
You might also want to grab some new drive shaft bolts and locknuts. It's a good thing to do, plus the nuts @ the transfer case look like they are starting to round off.

The bolts are 1 1/8" X 3/8" UNF(don't use coarse thread hardware) part #509045P and the nut part # NZ606041L. You can also get a complete hardware kit (DA1123) > Range Rover Discovery Defender Driveshaft Drive Shaft Bolt Nut
Many places sell this kit, like L8 on ebay > https://www.ebay.com/itm/Land-Rover-...4383.l4275.c10

 

Any particular reason not to use coarse thread hardware? I've got grade 8 3/8" coarse at both diffs.

 

The simple answer is a fine thread bolt is stronger than a coarse thread. I'm not going to bore you with details that are an easy search on google. The pic is just some real basic info.

For years I have only used fine threaded hardware for drive shafts on LRs and other vehicles that have a ton more horsepower and torque. Are you going to be fine with coarse threaded hardware, probably but my 1st choice is fine threads.
It's your call.