UZ Power Steering Cooler with Mounting Kit for Toyota Pickup & 4Runner 4x4 1979-1995

Product Overview

Universal-fit power steering fluid cooler designed for Toyota trucks, 4Runners, and any vehicle running a high-volume or high-pressure power steering system. When you upgrade to a Trail-Gear Power Flow™ 1,650 PSI pump, add a ram assist, or run full hydraulic steering, your power steering system generates significantly more heat than the factory setup was designed to handle. This Trail-Gear PS Cooler is the essential thermal management solution — protecting your steering pump, steering box, and hydraulic ram from fluid overheating and premature failure. Includes a complete mounting kit for straightforward installation in front of the radiator.

This cooler is also required equipment when running Trail-Gear's Power Flow™ pump kits. Using a high-output pump without a cooler on the low-pressure return side may cause pump failure and will void the Trail-Gear warranty — making this cooler a non-negotiable part of any serious steering upgrade.

Fitment

Year	Model	Engine
1979–1995	Toyota Pickup (4WD)	20R, 22R, 22R-E, 22R-TE (4-cyl); 3VZ-E (V6)
1985–1995	Toyota 4Runner	22R-E, 22R-TE (4-cyl); 3VZ-E (V6)
1989–1995	Toyota Pickup (V6)	3VZ-E 3.0L V6
1995–2004	Toyota Tacoma	2.7L 2RZ-FE (4-cyl); 3.4L 5VZ-FE (V6)
1995–2002	Toyota 4Runner (3rd Gen)	3.4L 5VZ-FE V6; 2.7L 2RZ-FE
1979–2004	Toyota Hilux (Global)	All engines — universal fitment
All Years	Custom / Rock Crawler / Off-Road Builds	Any engine — universal fitment with high-output PS pump or hydraulic steering

Important: This is a universal cooler — it is not vehicle-specific and does not require VIN verification. It fits any application on the low-pressure return side of the power steering system. Confirm hose fitting sizes and routing before ordering. Required on the low-pressure side when running Trail-Gear Power Flow™ 1,650 PSI pumps — use without a cooler voids the pump warranty.

Frequently Asked Questions

Q: Do I need a power steering cooler if I'm upgrading to a Trail-Gear Power Flow™ pump?
A: Yes — a power steering fluid cooler is required when running Trail-Gear's Power Flow™ 1,650 PSI pump. Trail-Gear explicitly states that operating the high-output pump without a cooler on the low-pressure return side may cause premature pump failure and will void the pump warranty. The stock Toyota power steering system produces around 1,300 PSI at 1 GPM; the Power Flow™ pump produces 1,650 PSI at 5 GPM — a significant increase in heat generation that the factory system cannot dissipate.

Q: Where does this cooler install in the power steering system?
A: The PS Cooler installs on the low-pressure return line — the line running from the steering box or orbital control valve back to the pump reservoir. It mounts in front of the radiator, where it receives direct airflow. Do not install it on the high-pressure line between the pump and steering box.

Q: Will this cooler work with my factory Toyota steering pump?
A: Yes. While this cooler is essential for high-output pump upgrades, it is also beneficial on factory Toyota steering systems in vehicles used for rock crawling, slow trail work, or any application where the steering wheel is held at full lock for extended periods. Sustained low-speed steering generates more heat than highway driving, and a cooler prolongs fluid and pump life in any Toyota off-road build.

Q: What hose fittings does this cooler use?
A: Verify fitting sizes before ordering — the PS Cooler uses standard low-pressure power steering return line connections. Most Toyota truck applications use 5/16" or 3/8" ID low-pressure return hose. The Trail-Gear Power Flow™ High-Flow Cooler (a separate product) uses #8 male JIC fittings for high-flow steering lines. Confirm which cooler variant matches your specific pump and hose kit configuration.

Q: Is this the same cooler included in Trail-Gear's full hydraulic steering kits?
A: The Trail-Gear PS Cooler is included as a component in Trail-Gear's Full Hydraulic Steering Kit (130305-1-KIT) and in select Power Flow™ pump kits. If you already have one of these complete kits, you may already have this cooler. It is also available separately for builders adding cooling to an existing steering upgrade.

Common Symptoms of Power Steering Overheating

• Steering pump groaning or whining after extended slow-speed trail use or repeated lock-to-lock turns
• Power steering fluid that appears dark brown or black, or has a burnt smell when checked on the dipstick
• Stiff or unresponsive steering when the system is hot, returning to normal after cooldown
• Premature steering pump failure — especially common when running high-output pumps without a return-line cooler
• Fluid foaming in the reservoir — indicates overheating has degraded the fluid's viscosity and air-separation properties
• Steering box or orbital valve leaking — heat cycling from chronic overheating accelerates seal degradation in steering components

 

Why Your Toyota Steering System Needs a Cooler

Toyota's factory power steering systems were designed for highway and light off-road use — not the sustained slow-speed stress of serious trail driving. When you're creeping through rock gardens, making repeated lock-to-lock inputs, or running a high-output pump pushing 1,650 PSI and 5 GPM, your steering fluid temperature climbs rapidly. Unlike engine coolant or transmission fluid, the factory Toyota steering system has no thermal management — heat builds until it destroys the fluid, and then the pump, and eventually the box or orbital valve.

The Trail-Gear PS Cooler solves this problem directly. By routing the low-pressure return flow through a 9" x 8" fin core mounted in front of the radiator, the cooler sheds heat before fluid cycles back into the pump — keeping temperatures stable even during all-day trail use. Toyota enthusiasts on IH8MUD and YotaTech have documented pump life extending dramatically after adding a return-line cooler, with common reports of steering staying responsive and quiet well past the point where uncooled systems begin groaning and degrading.

If you're running a Trail-Gear Power Flow™ pump, this cooler isn't optional — it's a warranty requirement and a mechanical necessity. If you're running a stock pump on a truck that sees serious trail use, it's the cheapest insurance you can buy against a several-hundred-dollar pump replacement. Either way, the PS Cooler belongs in any Toyota off-road build that takes the steering system seriously.