I have this nice, extra 4" x 4" oil cooler lying around. All this talk about the PS dying I wonder if I put the cooler in the lines somewhere, probably return, might be a good idea. Any thoughts?

 

First thing I would do BEFORE MODIFYING it is...
Check to see if your car is covered by the extended warrenty.....
If it is not due to miles or production date, guess you could experiment....
A couple thoughts....while the return line is mostly a standpipe, so very low psi, I would be careful about increasing back pressure.... If the back pressure goes up much...you are just increaseing the load on the PS pump....kinda counter productive....
An observation....
Most folks that have failures usually have heavy 17+ rims.....cars run on 15 or 16 rims usually don't have seem to have PS pumps fail, and you would be amazed at how much more lively the car feels with a nice light tire/rim combo.....more MINI, IMO, MORE LIVELY!!
For some that want to "look" a certain way it might not be an option, but I have found myself running 15' more after spending a few winterwinters on them....car feels more tossable, moreclivrly...not as straight line stable, but more willing to turn, less truck like....

 

Zippy. Good point on the 17" rims. I have the factory BBS MINI rims and while they look great they weigh a ton. With the tire they're a bruising 55lb each. My pump failed at 11 years 170k which for an electric pump in Florida isn't too bad. I'm certain my PS fan was out of commission for a good bit of that time.

I wouldn't go to the trouble of trying to install an oil cooler. Most pump failure is worn out brushes and commutator. Keep in mind the pump runs 100% of the time at about 70% capacity at rest and 100% under load. The electric fan supposedly help keep the electronics cool. Replacing the pump is pretty easy. Labor intensive but very basic mechanic skills.

 

I hadn't thought of the bigger tires/rims. I think the pump has already been replaced as all the hose clamps have been replaced with worm gear clamps. I'm in the habit of not turning the wheel unless I am moving, rarely turning when not moving.