[00xj54]

Well the 00-01 have low pinion D30 in the front. What does that mean? and is better then the high pinion?

[LankyXJ]

I know, rather I think, for the most part it just refers to the fact that the high pinion differential housing actually sits higher on the axle than the low pinion. So in essence, you have slightly more clearance in the high rather than low pinion. I'm pretty sure the spline count, ring gear, and shaft diameters are the same. The U-Joints may be different based upon year.

[Alexia]

High pinion, the drive shaft comes in on the top half of the differential, giving better clearance.

[LankyXJ]

Originally Posted by Alexia

High pinion, the drive shaft comes in on the top half of the differential, giving better clearance.

So the differential housing is still in the same place then on the axle?

[FrankZ]

The HP is a stronger axle, and yes they are both a drivers side drop.

[Alexia]

Originally Posted by XJer1302

So the differential housing is still in the same place then on the axle?

Yes, exactly.

[toledotimber]

The high-pinion version also has reverse-cut gears which are slightly stronger.

[EricsXJ]

Originally Posted by 00xj54

Well the 00-01 have low pinion D30 in the front. What does that mean? and is better then the high pinion?

The low-pinion has the pinion below the centerline of the axle. The high-pinion is above the centerline.

High-pinion is preferable for several reasons.

First is driveshaft clearance. With a HP axle, the driveshaft is a good 2 or 3 inches higher up than the LP. That could very well be the determining factor on whether or not your driveshaft survives a rock.

Second is driveshaft angle. A higher pinion gives you a much better driveshaft angle and this means less chance of vibration on a lifted XJ.

Third is strength. The ring and pinion on a HP axle is slightly stronger than on the LP.

That being said, lots of people use the LP Dana 30 without problems. Its the same axle used in the TJs. If you are going to lift it above 5" I think it would be a very good idea to look for a HP, or if you ever just have a good opportunity to get one. Make sure you have at least some lift however or the driveshaft might make contact with your exhaust.

[cj7xjmj]

Like Eric said the only real difference is in where the pinion is in relation to the centerline of the axle. As for which is stronger HP or LP diffs... this debate will rage for yrs. The ring gear is the only thing that is not interchangeable between the 2. Carriers, axle shafts, knuckles are all the same. Install kits are different as well

[BIGNUTT]

Yeap I've had a 2000 (lp d30) lifted with a Rustys 4.5" and I got vibes up front when in 4wd because of the pinion angle.

I now have a '99 (HP d30) and RE 4.5" and no vibes at all ever.

[BIGNUTT]

Originally Posted by cj7xjmj

Like Eric said the only real difference is in where the pinion is in relation to the centerline of the axle. As for which is stronger HP or LP diffs... this debate will rage for yrs. The ring gear is the only thing that is not interchangeable between the 2. Carriers, axle shafts, knuckles are all the same. Install kits are different as well

There is ZERO debate on strength. HP axle in a front axle application IS stronger, by how much? Thats the debate some say 10% some say 30%. Just like a HP axle in the rear is weaker because of which side of the gears are being run (coast side or drive side)