The Jeep Gladiator stands out as a tough, versatile truck. But if you’re thinking of upgrading, two options grab attention: the 35S and 37S packages. Both transform the Gladiator into a more serious off-road machine, but they offer different experiences. Knowing the differences helps you choose the right fit for your adventures, daily driving, and budget.
What Are The Jeep Gladiator 35s And 37s?
Both 35S and 37S are popular upgrade packages, mainly for off-road enthusiasts. The number refers to the tire size: 35-inch for 35S, 37-inch for 37S. These packages often include tire upgrades, lift kits, suspension tweaks, and supporting hardware. Some dealers offer these as pre-built packages, while many owners build their own versions.
Key upgrades usually include:
- Larger tires (35″ or 37″)
- Suspension lift (2–3.5 inches)
- Upgraded shocks
- Reinforced axles or driveshafts
- Fender modifications
- Recalibrated speedometer
The changes affect driving feel, capability, and appearance. But the gap between 35S and 37S is bigger than you might expect.
Performance And Handling Differences
When you move from 35S to 37S, the Gladiator’s abilities and behavior change a lot. Let’s compare them directly:
| Feature | 35S Package | 37S Package |
|---|---|---|
| Tire Size | 35-inch | 37-inch |
| Lift Height | 2–2.5 inches | 3–3.5 inches |
| Ground Clearance | ~12.5 inches | ~13.5 inches |
| Approach Angle | 42° | 44° |
| Fuel Economy | ~16–18 mpg | ~14–16 mpg |
| Ride Comfort | Good | Moderate |
35S upgrades give you a strong boost in ground clearance and off-road power, but keep the Jeep closer to factory comfort and handling. 37S takes things further, with more clearance and aggressive looks, but can feel stiffer and heavier, especially on pavement.
Off-road Capability
If you plan to crawl over rocks or deep mud, the 37S package offers clear benefits:
- Better approach and departure angles: You’re less likely to scrape bumpers or get stuck.
- Higher ground clearance: Easier to clear big obstacles.
- Tougher stance: 37″ tires can handle more abuse.
But these upgrades come with trade-offs. The Gladiator’s engine and gearing must work harder to spin bigger tires. Without re-gearing, acceleration and towing can suffer.
On-road Experience
Most Gladiator owners spend plenty of time on highways and city streets. Here, the 35S package keeps things simple:
- Easier handling: Less sway and bounce.
- Better fuel efficiency: Less rolling resistance.
- Quieter ride: Smaller tires make less noise.
The 37S package can feel rougher and louder. Cornering and braking need more attention, especially in wet conditions.
Cost And Maintenance
Upgrading isn’t just about tires and lifts. There are hidden costs, especially with 37S builds.
| Upgrade | 35S Average Cost | 37S Average Cost |
|---|---|---|
| Tires & Wheels | $2,000–$2,500 | $2,500–$3,500 |
| Suspension/Lift Kit | $1,000–$1,500 | $1,500–$2,000 |
| Supporting Mods | $800–$1,200 | $1,500–$2,500 |
| Total Estimate | $3,800–$5,200 | $5,500–$8,000 |
37S builds almost always require extra parts:
- Re-gearing axles: Fixes power loss and restores towing. Cost: $1,500–$2,500.
- Upgraded brakes: Needed for extra weight.
- Fender trimming: Prevents rubbing.
Maintenance costs also rise. Bigger tires wear faster and put more strain on suspension parts. Insurance may increase, too.
Real-world Examples And Insights
Many Jeep owners share their experiences online. Here’s what they report:
35S owners say:
- The Jeep feels balanced and fun.
- Daily driving is easy, with few downsides.
- Factory warranty often covers most upgrades.
37S owners love:
- The bold, aggressive look.
- Easier trail rides in tough areas.
- “Wow factor” at shows and events.
But some regret the extra cost and complexity. For example, gearing issues can make the Jeep sluggish, especially if you don’t upgrade the axles. Another common mistake: skipping brake upgrades, which can lead to longer stopping distances.
Non-obvious insight: Bigger is not always better. Many new owners chase the largest tire size without considering the impact on daily driving and reliability. Also, resale value can drop if upgrades aren’t done professionally.
Choosing The Right Package
Before you decide, think about these key points:
- Usage: If you spend most days on pavement, 35S is easier to live with. If you chase tough trails, 37S is worth the effort.
- Budget: 37S costs more up front and over time.
- Technical skill: Building a 37S Gladiator often needs expert help.
- Warranty: Some upgrades may void factory coverage.
- Local laws: Some states limit tire size or bumper height.
Ask yourself: do you want a daily driver with off-road options, or a dedicated trail rig?
Pros And Cons Summary
Here’s a quick summary for easy reference:
| Package | Pros | Cons |
|---|---|---|
| 35S | – Balanced ride – Lower cost – Easier daily use | – Less extreme off-road – Less visual impact |
| 37S | – Maximum off-road – Bold appearance – More ground clearance | – Higher cost – Complex upgrades – Reduced fuel economy |
Frequently Asked Questions
What Is The Main Difference Between The Gladiator 35s And 37s?
The biggest difference is tire size and the related upgrades. 37S includes 37-inch tires, higher lifts, and extra hardware, making the Jeep more capable but also more expensive and harder to drive daily.
Will Bigger Tires Affect My Jeep’s Warranty?
Yes, some upgrades for 37S (like axle swaps or lifts) might void parts of the factory warranty. Always check with your dealer before making changes.
Is Re-gearing Necessary For 37s Builds?
For most 37S builds, re-gearing is strongly recommended. It restores power, helps towing, and keeps the engine running efficiently.
How Does Fuel Economy Change With 35s Vs 37s?
Expect a drop in fuel economy. 35S gets about 16–18 mpg, while 37S drops to 14–16 mpg, depending on driving style and other mods.
Where Can I Find Reliable Upgrade Parts And Advice?
Check trusted sources like Quadratec for parts and community advice.
Upgrading your Jeep Gladiator is an exciting project. Whether you choose 35S or 37S, plan carefully, budget for hidden costs, and enjoy the ride.
Both packages can transform your Jeep, but the best choice depends on your needs, skills, and style.
