'93-'98 V8 Power Steering Cooler

Here's another great ZJ mod. I found out that export Grand Cherokees get a power steering cooler. This is an excellent add-on for those who drive their Grand Cherokees in a spirited fashion <g> or if you tow a lot. If you work the steering or carry a heavier load, the power steering fluid heats up, and can eventually cause seal and other failures in the box and pump as it loses it's lubricity. Note that all Grand Cherokees with a factory trailer tow option come with special high temperature seals on the power steering pump and box. That plus the cooler on export vehicles indicates to me Chrysler is well aware of power steering fluid cooling problems.

I am not using the export cooler, as I don't know what it looks like and you can't order export parts here in the US anyway. I found a better and easier mod, and it uses all factory parts, is easy to install and works on all V8 Grand Cherokees. Unfortunately if you have a 6 cyl, you'll have to figure something else out.

I found out that the auxiliary auto trans cooler for the 6 cyl Grand Cherokees will work extremely well as a power steering cooler for the V8. The V8 uses an auxiliary trans cooler on the RH (passenger) side of the car and there is no cooler on the LH (driver) side. The 6 cyl Grand Cherokee uses an auxiliary trans cooler on the LH side, which is what I am using for a power steering cooler on the V8.

Photo A shows the power steering cooler mounted in front of the radiator on the LH (driver's) side.

Photo B shows both the transmission and power steering coolers mounted.The great part is that Mopar parts sells a complete 6 cyl cooler add-on kit for those who don't have an auxiliary trans cooler on their 6 cyl Grand Cherokee. The kit is available from your dealer under part number 82203002 and costs only about $50. This kit is complete, it includes the cooler, plus all mounting hardware, hard lines, hoses, etc. The hard lines attach to the cooler with short rubber elbows and route very nicely around the left hand (driver's side) of the radiator.

Normally they would attach in-line to the in-tank radiator trans cooler on the LH (driver) side on 4.0L 6-cyl Grand Cherokee, but the transmission cooler and associated lines for the V8 models are on the other side. Since the intended use here is for power steering, all you have to do is cut the flare fitting ends plus a few additional inches of tube off of the hard lines (use a small tubing cutter for a clean cut). Cut them so they end up pointing towards the steering box and pump. Then remove the low-pressure return hose from the power steering box to the pump.

Now you'll need two hoses, one to go from the outlet on the steering box to the inlet on the cooler, and another to go from the outlet on the cooler back to the inlet on the pump. You'll be able to re-use the return hose you removed earlier, but you'll also need an additional piece of 3/8" power steering hose, about 1 foot should do it.

Trim the hoses to the proper length and attach over the lines with clamps. Besides the parts included in the cooler kit, you will need about a foot of additional 3/8" or 11/32" power steering (or transmission) hose, and possibly a couple of additional 3/8" hose clamps.

Photo C shows the hose connections between the hard lines from the cooler, the power steering box, and the pump.

Make sure you attach the low pressure output line from the power steering box to the line which enters the bottom fitting on the cooler. The other hose should be connected from the line which exits the top of the cooler back to the power steering pump inlet. This is the low pressure return side of the circuit. Routing in this manner insures that the fluid flows in the bottom and out the top of the cooler which causes air to be automatically purged from the system. Be sure to bleed the entire steering system of air after the cooler is installed. This is normally accomplished by lifting the front tires off the ground, and cycling the wheels back and forth lock to lock about 20 times with the engine running.