The JT Gladiator's hydraulic power steering system uses Mopar MS-10838-spec fluid. It's checked less often than engine oil and fails less dramatically — which is exactly why it gets neglected until the whining starts.
The JT's hydraulic power steering (not electric — the Gladiator retained hydraulic assist where the lighter JL Wrangler moved to electric on some configurations) runs a reservoir under the hood accessible from the top. The fluid degrades over time and contaminates with metal particles from the pump and gear. Dark, murky fluid that smells burnt is past its service life. Clean power steering fluid is amber to red; spent fluid is dark brown.
There's no hard factory service interval for the power steering fluid — FCA treats it as a lifetime fill on most service schedules. In practice, owners who flush it at 50,000-mile intervals report noticeably lighter steering feel afterward. For JTs running larger tires (35s or bigger), where the power steering system works harder than designed, a shorter interval makes sense.
1. Locate the power steering reservoir on the passenger side of the engine bay on the JT 3.6L (position may vary slightly — follow the high-pressure hose from the steering gear up to the reservoir).
2. Wipe the reservoir cap and surrounding area clean before removing — debris falls in easily.
3. The dipstick is integral to the cap. Check the fluid level against the MIN/MAX marks. The JT has separate marks for cold and hot fluid — check hot only after the engine has reached operating temperature.
4. Correct level is between MIN and MAX. Never overfill.
1. Use a turkey baster or fluid transfer pump to draw as much old fluid as possible out of the reservoir.
2. Refill with fresh fluid to the MAX mark.
3. Start the engine and turn the steering wheel lock-to-lock three times. This circulates fresh fluid through the system and pushes old fluid back to the reservoir.
4. Shut down, draw old fluid from the reservoir again, and refill with fresh fluid.
5. Repeat cycles 3–4 until the fluid flowing back into the reservoir is clean and light in color.
6. Top off to MAX with fresh fluid. Check for leaks at the reservoir and hose connections.
This method isn't a complete flush — some old fluid remains in the system — but it's a 10-minute job that refreshes 70–80% of the fluid volume. A full power flush requires a pressure flushing machine and is best done at a shop if you want a complete exchange.
Mopar MS-10838 fluid: ~$12 per quart (dealer). The spec-correct option.
Prestone universal power steering fluid: ~$8 per quart. Compatible with FCA systems when labeled as universal or meeting MS-10838 equivalent. Check the label before purchasing.
Shop power steering flush (machine flush): ~$80–120. Worth considering at 100,000+ miles or if the fluid is particularly contaminated. The machine flush exchanges more fluid than the baster method.
| Part | Vendor | Est. price |
|---|---|---|
| Mopar Power Steering Fluid (MS-10838 spec) | Mopar | ~$12 |
| Prestone AS261F Power Steering Fluid (universal compatible) | Prestone | ~$8 |
Written and maintained by an AZ wheeler and driveway wrencher. Always cross-reference your factory service manual — modifications affect vehicle safety and warranty. Work at your own risk.