If you’re building a serious off-road rig and need 38-inch mud tires for 20-inch rims, you’re in the right place. We researched and compared the top models from leading brands, analyzing manufacturer specifications, published industry standards, and aggregated owner feedback. Our evaluation focuses on real-world performance in mud, durability on rocks, road manners, and value. Whether you drive a lifted truck, Jeep, or SUV, this guide will help you choose the right tire for your needs and budget.
We considered tread design, compound hardness, sidewall strength, and load ratings to rank these tires. Keep in mind that 38-inch tires on 20-inch rims are a niche size, so availability and fitment can vary. Always check your vehicle’s clearance and gearing before purchasing. Here are our top picks after thorough research.
| Photo | Product | Score | Buy |
|---|---|---|---|
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Nitto Trail Grappler M/T Best Overall 38×13.50R20, Load Range E, 3-ply sidewall |
9.0 | 🛒 Check Price |
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BFGoodrich Mud-Terrain T/A KM3 Best for Durability 38×13.50R20, Load Range E, 3-ply sidewall |
8.7 | 🛒 Check Price |
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Toyo Open Country M/T Best Value 38×13.50R20, Load Range E, 3-ply sidewall |
8.4 | 🛒 Check Price |
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Cooper Discoverer STT Pro Best for On-Road Comfort 38×13.50R20, Load Range E, 3-ply sidewall |
8.1 | 🛒 Check Price |
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Mickey Thompson Baja Boss M/T Best for Extreme Mud 38×13.50R20, Load Range E, 3-ply sidewall |
8.8 | 🛒 Check Price |
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Federal Couragia M/T Budget Pick 38×13.50R20, Load Range E, 2-ply sidewall |
7.8 | 🛒 Check Price |
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Ironman All Country M/T Solid All-Rounder 38×13.50R20, Load Range E, 2-ply sidewall |
7.3 | 🛒 Check Price |
1. Nitto Trail Grappler M/T: Best Overall
In our evaluation, the Nitto Trail Grappler M/T stands out as the best 38-inch mud tire for 20-inch rims. Based on manufacturer specs and owner feedback, it delivers exceptional mud performance thanks to its aggressive tread pattern and large shoulder lugs. The 3-ply sidewall provides excellent durability for rock crawling and rough trails, while the variable pitch design helps keep road noise manageable for a mud tire. Many owners report over 30,000 miles of tread life, which is impressive for this size.
However, the Trail Grappler is heavy, which can impact acceleration and fuel economy on daily drives. If you primarily drive on pavement and only occasionally hit mud, you might prefer a lighter, more road-friendly tire. Also, some users note that it can be noisy at highway speeds. This tire is best for serious off-roaders who need maximum traction and durability without compromising too much on-road civility.
- Aggressive mud tread with variable pitch for reduced road noise
- Reinforced sidewall with three-ply construction for puncture resistance
- Excellent self-cleaning in mud and soft terrain
Pros: Outstanding traction in deep mud and loose soil; Long tread life compared to many competitors
Cons: Heavy weight can affect fuel economy and acceleration
2. BFGoodrich Mud-Terrain T/A KM3: Best for Durability
BFGoodrich’s Mud-Terrain T/A KM3 is a legend in off-road durability, and our research confirms it’s a top contender for 38-inch mud tires on 20-inch rims. The KM3 features a Mud-Philic compound that maintains flexibility in cold conditions and a self-cleaning tread design that sheds mud effectively. The sidewall armor is reinforced with an extended shoulder that protects against sharp rocks, making it a favorite among rock crawlers. Owner feedback consistently praises its toughness and long lifespan.
On the downside, the KM3 can feel stiff on pavement, and some owners report increased road noise after moderate wear. It also tends to be pricier than some alternatives, which may deter budget-conscious buyers. If you frequently traverse sharp rocks or debris, this tire is an excellent choice, but if you want a smoother highway ride, consider a less aggressive option. This tire is best for hardcore off-roaders who prioritize durability over on-road comfort.
- Mud-Philic compound with self-cleaning tread bars
- Sidewall armor with extended shoulder for cut resistance
- CoreGard Max technology for enhanced puncture protection
Pros: Extremely tough sidewall resists cuts and abrasions; Consistent traction in mud and on rocks
Cons: Stiffer ride on pavement compared to some competitors
3. Toyo Open Country M/T: Best Value
The Toyo Open Country M/T offers impressive value for a 38-inch mud tire on 20-inch rims. Our evaluation of its specs shows a deep tread depth that provides excellent grip in mud and soft terrain, while stone ejectors help prevent damage. Owner feedback highlights its balanced performance: it handles well on pavement for a mud tire and wears evenly over time. For the price, it delivers solid off-road capability without breaking the bank.
However, the sidewall is not as robust as the BFGoodrich or Nitto, making it more susceptible to cuts in rocky environments. Some owners also note that it can be noisy at highway speeds. If you primarily drive on muddy trails and gravel roads with occasional rocks, this tire is a great value. But if you frequently tackle sharp rocks, you may want a stronger sidewall. This tire is best for budget-minded off-roaders who still want reliable mud performance.
- Deep tread depth for long wear and mud traction
- Stone ejectors prevent stone drilling
- Balanced off-road capability with decent road manners
Pros: Competitive price for a 38-inch mud tire; Good tread life and even wear
Cons: Sidewall not as tough as premium competitors
4. Cooper Discoverer STT Pro: Best for On-Road Comfort
Cooper’s Discoverer STT Pro is designed to offer a more civilized on-road experience without sacrificing off-road capability. Based on our research, its Armor-Tek3 carcass provides solid durability, and the stone block technology helps prevent stone drilling. Owner feedback often mentions that it’s quieter than many competitors, making it a good choice for daily drivers who still want mud traction. It also performs well in snow, adding versatility.
However, some owners report that the tread wears faster in hot climates or under heavy loads. The sidewall, while strong, is not as thick as some premium tires. If you need a tire that balances off-road ability with daily driving comfort, the STT Pro is a strong pick. But if you prioritize extreme durability or maximum mud performance, other options may be better. This tire is best for those who use their vehicle as a daily driver with weekend off-road trips.
- Armor-Tek3 carcass construction for durability
- Stone block technology to prevent stone retention
- Quieter on-road than many mud tires
Pros: Relatively low road noise for a mud tire; Good traction in mud and snow
Cons: Tread life may be shorter in high-heat conditions
5. Mickey Thompson Baja Boss M/T: Best for Extreme Mud
The Mickey Thompson Baja Boss M/T is built for extreme off-road conditions, and in our evaluation, it excels in deep mud. Its aggressive tread design features large blocks and mud scoops that eject debris quickly, maintaining grip. The PowerPly XD sidewall is among the toughest in its class, offering excellent protection against cuts and punctures. Owner feedback from hardcore off-roaders is overwhelmingly positive, praising its ability to claw through thick mud and over rocks.
However, the Baja Boss is heavy and can be loud on the highway, which may be a drawback for daily drivers. It also comes at a premium price. If you frequently encounter deep mud and rocky trails, this tire is a top performer. But if you spend most of your time on pavement, you might find it too harsh. This tire is best for dedicated off-roaders who want maximum traction in extreme conditions.
- PowerPly XD sidewall for extreme durability
- Large tread blocks with mud scoops for self-cleaning
- Enhanced tread compound for cut and chip resistance
Pros: Exceptional mud traction and self-cleaning; Very strong sidewall for rock crawling
Cons: Heavy and can be noisy on pavement
6. Federal Couragia M/T: Budget Pick
Federal Couragia M/T is a budget-friendly option for those who need 38-inch mud tires on 20-inch rims without spending a lot. Based on our research, it offers an aggressive tread pattern that performs adequately in mud and loose soil. Owner feedback indicates it’s a good entry-level mud tire for occasional off-road use. The reinforced bead area helps with stability at lower pressures.
However, the 2-ply sidewall is a significant weakness compared to the 3-ply construction of premium tires, making it more prone to punctures in rocky terrain. Road noise and vibration are also more noticeable. If you’re on a tight budget and only tackle mild mud trails, this tire can work. But for serious off-roading or frequent rock crawling, we recommend investing in a more durable tire. This tire is best for occasional off-roaders who prioritize cost savings.
- Aggressive tread pattern with deep grooves
- Reinforced bead area for better stability
- Affordable price point for 38-inch size
Pros: Very attractive price for a 38-inch mud tire; Decent mud traction for the cost
Cons: 2-ply sidewall is less durable than competitors; Higher road noise and vibration
7. Ironman All Country M/T: Solid All-Rounder
Ironman All Country M/T is another budget-conscious option that provides reasonable off-road capability for the price. Our evaluation of its specs shows a multi-angle tread that works in mud and snow, and a reinforced shoulder offers some protection. Owner feedback suggests it’s a decent tire for light to moderate off-road use, especially for those on a limited budget.
However, like many budget tires, the 2-ply sidewall is a concern for durability in harsh conditions. Road noise and vibration are common complaints, and the tread life may be shorter than premium tires. If you need a 38-inch mud tire for occasional off-road trips and want to save money, the Ironman could be a viable option. But for frequent or severe off-roading, we recommend stepping up to a tire with a stronger sidewall. This tire is best for casual off-roaders who prioritize low cost.
- Multi-angle tread design for mud and snow
- Reinforced shoulder for off-road protection
- Affordable alternative to premium brands
Pros: Good value for the price; Decent traction in mud and snow
Cons: 2-ply sidewall limits durability; Can be noisy and vibrate at highway speeds
Frequently Asked Questions
Will 38-inch mud tires fit on 20-inch rims without modifications?
Fitment depends on your vehicle’s suspension, lift, and wheel offset. Generally, 38-inch tires require a significant lift (4-6 inches or more) and may need trimming or aftermarket fenders. Always check your vehicle’s clearance and consult a professional before purchasing. We recommend measuring your current setup and comparing with the tire’s overall diameter and width.
What is the difference between a 2-ply and 3-ply sidewall?
3-ply sidewalls have an extra layer of rubber and reinforcement, making them more resistant to cuts, punctures, and impacts. They are preferred for rock crawling and extreme off-road conditions. 2-ply sidewalls are lighter and more affordable but less durable. For 38-inch mud tires on heavy vehicles, a 3-ply sidewall is generally recommended for safety and longevity.
How do 38-inch mud tires affect fuel economy and performance?
Larger, heavier tires increase rolling resistance and unsprung weight, which can reduce fuel economy by 10-20% and decrease acceleration. They also require recalibrating your speedometer and may affect braking distance. Re-gearing your differentials can help restore performance. Consider these factors before upgrading to 38-inch tires.
What is the best tire pressure for 38-inch mud tires on the road?
Recommended pressure varies by tire model and load, but typically between 35-45 psi for highway driving. For off-road, lower pressures (15-25 psi) improve traction. Always follow the manufacturer’s guidelines and adjust based on your vehicle’s weight and driving conditions. Underinflation can cause heat buildup and tire failure.
How long do 38-inch mud tires typically last?
Tread life depends on driving habits, terrain, and tire quality. Premium mud tires like the Nitto Trail Grappler or BFGoodrich KM3 can last 30,000-40,000 miles with proper rotation and inflation. Budget tires may wear faster, around 20,000-30,000 miles. Aggressive off-road use significantly reduces lifespan.
Our Verdict
After researching and comparing the top 38-inch mud tires for 20-inch rims, our top pick is the Nitto Trail Grappler M/T for its outstanding balance of mud traction, durability, and on-road manners. For those who need extreme durability and don’t mind a stiffer ride, the BFGoodrich Mud-Terrain T/A KM3 is an excellent runner-up. Choose based on your primary terrain and budget.
