A “While I’m There” DIY Jeep Maintenance Marathon

When it comes to wrenching on your vehicle, sometimes a simple job evolves into a sprawling maintenance marathon. That’s exactly what happened when I decided to tackle a 10-year, 100,000-mile service on my 2013 Jeep Wrangler Unlimited Rubicon JKU. What started as a plan to replace the oil cooler turned into a long list of “while I’m there” repairs and tune-ups—everything from draining coolant to swapping out spark plugs and coil packs.

Was it a little chaotic? Absolutely. But it was also deeply satisfying, and I’ve got plenty of tips to share from the adventure.

Why So Many Repairs?

This marathon of maintenance kicked off when I discovered that my oil cooler housing was leaking—a common issue on this Jeep model. After consulting my trusty endoscope camera, I saw that the seals were failing. Since the intake manifold had to come off to access the cooler, I figured I might as well tackle a slew of other repairs while everything was apart.

In addition to replacing the oil cooler, my to-do list grew to include:

Replacing the PCV valve.

Installing new ignition coils and spark plugs.

Swapping out the thermostat housing and radiator hoses.

Cleaning and refreshing components that hadn’t seen attention in years.

This “while I’m there” philosophy isn’t just practical—it’s a chance to refresh parts of your vehicle that are often overlooked but essential for long-term reliability.

The Parts Lineup

Before diving in, I lined up all the parts I’d need for the job. Most of them came from my Amazon shopping list (Jeep Wrangler Maintenance Essentials), including:

Dorman Aluminum Housing Oil Cooler: Affordable but, as I later discovered, not without its flaws.

Bosch Ignition Coils: Known for quality and compatibility with Mopar specs.

E3 Spark Plugs: A budget-friendly option at just $6.99 each.

Thermostat Housing and Radiator Cap: Often-overlooked components that play a big role in keeping your engine cool.

Gunk Engine Degreaser: My secret weapon for cleaning grime and restoring parts to their former glory.

With everything ready, it was time to get started.

The Journey: Challenges, Victories, and Setbacks

Taking apart the intake manifold was the first step, and let me tell you, it’s a messy job. From carefully removing hoses with pliers to accessing hidden bolts, it’s a reminder that patience is a virtue in DIY maintenance. Along the way, I took extra care to inspect for leaks and clean components, using a mix of brake cleaner, shop vacs, and good old-fashioned elbow grease.

The PCV valve and thermostat housing replacements were straightforward, thanks to having the intake manifold already removed. Spark plugs and coil packs also went in without a hitch, although I can’t stress enough how much a dab of anti-seize on the plugs helps during installation.

The real drama came with the oil cooler replacement. After installing the Dorman unit, I filled the Jeep with fresh oil, only to discover a massive leak the moment I started the engine. Oil had pooled in the galley, undoing hours of meticulous cleaning. Turns out, the seals on the new cooler had failed. Frustrated but determined, I tore everything apart again and replaced the faulty cooler with a new unit. Lesson learned: when it comes to deep internal parts, don’t skimp on quality.

The Final Stretch: Testing and Burping the Coolant System

Once the repairs were complete, it was time for the moment of truth. I started the Jeep, checked for leaks, and burped the cooling system using a specialized funnel—a tool I now consider a must-have. The engine ran smoothly, oil pressure was stable, and hot air flowed from the heater vents, signaling that everything was back in working order.

Takeaways from the Adventure

This marathon repair session reinforced a few key lessons:

Quality Matters: Skip the budget parts for critical components like the oil cooler. Stick with OEM or trusted brands.

Clean As You Go: Taking the time to clean parts and components not only makes reassembly easier but also extends the life of your vehicle.

Plan for the Unexpected: Tackling multiple jobs at once saves time in the long run, but be prepared for setbacks.

A Jeep Reborn

After all the effort, my 10-year-old Jeep is running like new and ready to hit the trails. These types of projects are never simple, but they’re worth it for the peace of mind and the satisfaction of knowing your vehicle is in top shape.

If you’re tackling a similar project, check out my Jeep Wrangler Maintenance Essentials list on Amazon for the tools and parts I used. And for more how-to videos and gearhead adventures, visit my YouTube channel, AutoEdits: youtube.com/@AutoEdits.

Until next time, happy wrenching—and don’t forget to enjoy your drive!