HP = High Pinion. Jeep used both versions High and Low.

 

High pinion is stronger than the low pinion, hence why it's an upgrade

 

^ Really?
The reason is usually for a reduced drive-line angle on a lifted rig.

 

yes it's stronger because of the way the gears are cut. Low pinion axles have the pinion pushing on the weak side of the ring gear.

The HP axle is an upgrade for those two reasons (drive line angle and the strength of the gears)

 

HP is stronger than LP.

 

Did they use the Chrysler rear end in the 4 cylinder models? I would hate to give that up for better gearing on larger tires.

 

Yes some did

 

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