When to replace oil pump

[capejeep99]

I'm replacing the clutch in my '99 xj manual 4.0 - 6 liter. While I have the transmission out I'm planning to replace the rear main seal and oil pan gasket. Looking for thoughts, while I have all these components removed, whether I should think about replacing the oil pump. While the vehicle was operational, I didn't really notice any oil pump issues, but figuring while I have all these components removed, would it be prudent to replace the oil pump? Thanks for any thoughts.

 

[Anak]

Probably not necessary. Maybe if you have 500K miles on the clock, but if it doesn't seem to have any oil issues I wouldn't change it. They are not known for having issues. There may be some new engine designs where the bean counters managed to screw up the oil pump, but the 4.0L predates that nonsense.

 

[75SV1]

What is your present oil pressure? How many miles on the clock? I have replaced an oil pump on one of my 4.0L. The oil pressure went from say 15 psi to 25 or 35. Maybe a bit higher. Still, you have to factor in, that the bearings would be worn. I replaced the main bearings on the mentioned 4.0l. Also, I'd replace the harmonic balancer. On my 2000 XJ, with 271K on it, the oil pump was fine. I think in the 40 psi. Piston cracked, so I put in a mini stroker.