Comparison / review: PSC versus Black Magic Brakes bolt-on power steering coolers

It’s a work in progress. I can definitively say the Derale 33603 cooler fits with -8AN on the passenger side, and I’m confident it will fit on the drivers side as well.

For the passenger side I installed an engine oil cooler kit that includes the Derale 33603, a thermostatic sandwich adapter, and a few other parts. I also bought -8AN tube fittings from PSC so it is easily removable and field serviceable.

The engine oil cooler runs great, and based on my idle/stopped measurements, there is at least a good 10-20 degree drop in engine oil temperature across the cooler once the thermostat blocks off the bypass. I’ll bet it will reject much more heat at higher engine and road speeds.

I also did the rear main seal while I had the oil out, and even threw in a high volume Melling pump for no good reason. (That pump was a beast to prime but works great.)

I have another 33603 cooler on hand for the power steering pump along with all the adapters and fittings I need to create a super short return line.
 
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This is the engine oil cooler kit I used:
https://www.amazon.com/dp/B004XONT6G/?tag=wranglerorg-20
The kit is advertised as having a non-thermostatic sandwich adapter but it actually came with a thermostatic one, which was a pleasant surprise. The sandwich adapter is short enough you can continue to use the oversized oil filters like the M1-301A. Stock filters will certainly work too, but the larger ones will have less pressure drop.

Instead of buying a standalone 33603 cooler for the power steering pump, I ordered this kit:
https://www.amazon.com/gp/product/B004XONS2G/?tag=wranglerorg-20
For whatever reason it is cheaper to buy this kit than a standalone 33603 cooler. Plus you get some leftover fittings to mess around with.
 
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This is the engine oil cooler kit I used:
https://www.amazon.com/dp/B004XONT6G/?tag=wranglerorg-20
The kit is advertised as having a non-thermostatic sandwich adapter but it actually came with a thermostatic one, which was a pleasant surprise. The sandwich adapter is short enough you can continue to use the oversized oil filters like the M1-301A. Stock filters will certainly work too, but the larger ones will have less pressure drop.

Instead of buying a standalone 33603 cooler for the power steering pump, I ordered this kit:
https://www.amazon.com/gp/product/B004XONS2G/?tag=wranglerorg-20
For whatever reason it is cheaper to buy this kit than a standalone 33603 cooler. Plus you get some leftover fittings to mess around with.
Interesting. I've been looking at whether it's possible to make a 3.6 oil cooler/filter work on a 4.0l. It's a thought piece at this point, but, in theory, it would be a easy way to cool, add additional oil filtration, and a temp sensor. :unsure:
 
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Interesting. I've been looking at whether it's possible to make a 3.6 oil cooler/filter work on a 4.0l. It's a thought piece at this point, but, in theory, it would be a easy way to cool, add additional oil filtration, and a temp sensor. :unsure:
That could be interesting. The advantage of the sandwich adapters is they are incredibly simple and easy to install and remove. So you have an oil out line and an oil in line just like a transmission. Then you plumb in whatever cooler you want.

The thermostatic ones have a manual thermostat similar to a coolant thermostat. There is a bypass hole that is normally open that most of the flow goes through. A small amount still goes through the cooler such as to not send a slug of cold oil through a hot engine. Once the thermostat heats up it blocks the bypass and all flow goes through the cooler.

Most oil thermostats are set at about 180 degrees, which is still more than enough temperature to cook out moisture. You'll still get oil temperatures well above that on occasion, but lowered by anywhere from 10-50 degrees depending upon conditions.
 
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I don't think I'd ever put an oil cooler on my Jeep. The block temperature is regulated by the cooling system, the thermostat, fan and radiator. If you run cool oil through the block the coolant will rise in temperature to maintain the correct block temperature. If you run hot oil through the block the coolant will run cooler to decrease the temperature of the block. As the engine is running the oil and coolant both play roles in cooling the engine but you don't need two systems to regulate the temperature unless one of them can't keep up. Since the cooling and oil passages are closely coupled in the block I don't see any need in our case for another cooler. The end result of a very high performance oil cooler is slower coolant flow which doesn't seem like something I'd want.
 
I don't think I'd ever put an oil cooler on my Jeep. The block temperature is regulated by the cooling system, the thermostat, fan and radiator. If you run cool oil through the block the coolant will rise in temperature to maintain the correct block temperature. If you run hot oil through the block the coolant will run cooler to decrease the temperature of the block. As the engine is running the oil and coolant both play roles in cooling the engine but you don't need two systems to regulate the temperature unless one of them can't keep up. Since the cooling and oil passages are closely coupled in the block I don't see any need in our case for another cooler. The end result of a very high performance oil cooler is slower coolant flow which doesn't seem like something I'd want.
As long as you're running a thermostatic oil cooler of a reasonable size, that feedback echo tends to be a non-issue.

The linked cooler is only rated to about 21,000 btu/hr of maximum heat rejection. (You can buy bigger ones of course.) Plus the thermostat ensures that oil that is too cold does not continue to get overcooled.

Meanwhile, driving at 70 mph on an average freeway, I get about 13 MPG, equivalent to 5.4 gallons an hour. A gallon of gasoline has about 116,090 btu. So you are burning 627,000 btu/hr. Roughly 30% of that is turned into power, or 73 horsepower. (Some of that is then lost in the drivetrain, engine friction, and belt drive.) Another 40% leaves the tailpipe. The remaining 30% leaves the cooling system. That's 188,000 btu/hr leaving the radiator.

Thus the addition of an oil cooler doesn't negatively impact the ability of the cooling system to cool. It can just as easily reject 165,000 btu/hr as 188,000. The thermostat just doesn't open quite as far. The rest of the coolant gets pumped through the heater core and remixed with the cooled coolant before recirculating through the block.

As to in the block, the advantage comes that the oil and coolant are now at more consistent temperatures. More consistent engine temperatures result in lower thermal stresses, and less overall wear.

In addition, since the oil temperature is thermostatically regulated, it now has a more consistent viscosity across a wide range of operating conditions. Thus less dramatic swings in oil temperature and viscosity occur, reducing the odds of engine wear from excessively low viscosity at high temperatures. The thermostat protects against high viscosity caused by overcooling.

Thirdly, reducing the peak temperatures of the oil will extend the life of the oil, allowing it to keep its properties consistent for a longer period of time. Theoretically you could extend your oil life interval, but I wouldn't recommend this for other reasons.

The only two scenarios I could see causing an issue would be a massively oversized oil cooler, or a non-thermostatically controlled oil cooler. If the oil is not hot enough, it will not lubricate as intended and it will collect moisture and fuel vapors.
 
In addition to that argument, both the thermostat in the coolant loop and in the oil loop are only proportional control devices. The hotter the coolant or oil, the more it opens.

Unlike more modern/complex controllers like the Proportional Integral Derivative (PID) controllers, they tend to not get into a feedback loop when used in parallel except in unique design circumstances. Two PID controllers can much more easily get into oscillating fights with one another.

One very common example of PID controllers fighting one another is a long line of cars that have active cruise control engaged, following a car with a mostly constant speed. Early in the line the cars in front will follow the lead car's speed easily, but oscillations will develop as slight variances in the speeds of the following cars create huge feedback waves. (This example is actually a huge design issue in self driving car schemes.)
 
since the oil temperature is thermostatically regulated, it now has a more consistent viscosity across a wide range of operating conditions
Sorry, didn't mean to suggest it was a bad idea or that they would fight each other, just I wouldn't do it. The oil is thermostatically controlled on a TJ, that is the function of the cooling system. You are not changing the temperature of the oil much at all because our massive engine block that the oil is pumping through is always about the same temperature. The thermostats will work together to maintain the same temperature regardless of the oil cooler. I know it sounds strange but the oil system on a TJ isn't independent of the coolant system, the passages are designed specifically as an oil to water cooler so you don't need an external one. Bad engine designs or small engine blocks often need coolers because there isn't enough flow in the engine to exchange heat. This isn't an issue on the 4.0. If you like the idea go for it. Trying to help you understand why it isn't often done even by folks that run in extreme temperatures.
 
Funny you mentioned a PID, that's what I use to measure the temp of my 42RLE.

pid.jpg


Jeep is cold, it's hot today.
 
Yup, no problem, I will take some pics tonight.
Here ya go @Irun it's a pretty standard setup.. the psc dual cooler with -6 lines.. only upgrade was I ditched the worm clamps for constant tension ones.. seems to work fine for a stock pump and non desert wheeling Trans operation... but I'm considering tearing it all out when I do the hydro assist .. I have never been unhappy with performance after following @mrblaine advice.. and when he says -8 return on the heatsink style single pass PS cooler coupled with a nice bar and plate style single pass Trans cooler I'm listening. I've researched a few competitors and pricing is similar to the Setrab. **edit to actually add the damn pictures... mobile app woes**

dual cooler driver.jpgdual cooler passenger.jpg
dual cooler wide.jpg
 
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Here are some photos of the 33603 oil cooler and kit on the PSC bracket. Note the original PSC steering cooler is still installed in the driver's side. I plan to swap it with the 33603 shortly.

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