Increase gas mileage by 1-2 mpg?

After two tanks I'm seeing a difference.

 

Maybe you forgot to put the serpentine belt on the pump, and the decreased workload on the engine is causing your MPG increase.

 

ha ha!

The pump was replaced because I'd run out of power assist when turning the wheel quickly, like when backing a trailer.

Spun easily when off the car.

I don't get it

 

A power steering pump is a parasitic drain on engine perfomormance and therefore gas mileage. If your old pump was binding or dragging the engine down, I suppose this is possible. But I've never heard of it.

Did you make any other changes? Maybe you just didn't drive it as hard on the last tank?

 

Yes it can!
One of the off road mags (can't remember which one) did a write up on bolt ons for Xj to increase H.P. and MPG. Cold air box, K&N filter and such. The biggest MPG increase they noted was when they replaced the old worn out PS pump. It was 1-2 MPG.

 

Could very well be.

No other changes 'cept the pump and a high pressure hose.

Musta cracked the old hose when swappin the pump.

 

I know this sounds weird but my handling and steering tightness improved when I put on a new high pressure hose. The difference was instantly noticeable.