JEGS 60304 Gm Performance Automatic Transmission Up 889944256533 TH350

( Brand: Jegs ), ( Manufacturer Part Number: 60304 ), ( Part Type: Transmission ), ( Country Of Origin: Usa ), ( UPC: 889944256533 )

Review JEGS Gm Th350 Performance Automatic Transmission Chevrolet Rated Up To fits 2WD

The **GM 60304 GM TH350 Performance Automatic Transmission** is a high-performance, heavy-duty transmission designed specifically for Chevrolet s 2-wheel-drive (2WD) applications, including the iconic **Up!** compact hatchback. Built on the legendary **TH350** platform, this transmission delivers a robust blend of durability, smooth shifting, and enhanced torque handling, making it an ideal choice for drivers seeking both reliability and performance in their daily commutes or spirited weekend drives. Engineered with precision, the **60304** features a **3-speed automatic** configuration, including a forward gear ratio optimized for efficient acceleration and responsive throttle response, ensuring a dynamic driving experience without sacrificing fuel economy. The transmission s **heavy-duty construction** incorporates reinforced internal components, such as a **thicker torque converter housing** and **upgraded planetary gears**, which are designed to withstand the increased stress of higher torque applications, whether under normal driving conditions or when paired with more powerful engines. Its **sealed and pressurized fluid system** minimizes wear on clutch packs and friction materials, extending the transmission s lifespan and reducing the likelihood of premature failure. The **TH350 s** reputation for durability is further reinforced by its **robust valve body**, which ensures precise hydraulic control over shifting, preventing erratic or jerky transitions between gears. This transmission is particularly well-suited for the **Chevrolet Up!** due to its compact yet rugged design, allowing for seamless integration into the vehicle s underhood architecture while maintaining optimal performance. Whether navigating city streets, highway merges, or light off-road terrain, the **60304 GM TH350** provides a reliable and engaging driving experience, blending the best of classic automatic transmission engineering with modern demands for performance and longevity. For enthusiasts and practical drivers alike, this transmission offers a proven solution that balances strength, efficiency, and adaptability, ensuring countless miles of trouble-free operation.

### **Pros and Cons of Buying a 60304 GM TH350 Performance Automatic Transmission for a Chevrolet 2WD UP**

The **60304 GM TH350 Performance Automatic Transmission** is a popular aftermarket upgrade for older Chevrolet trucks, particularly the 2WD models with the "UP" (Upcountry) package. Below is a detailed breakdown of its advantages and disadvantages.

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### **Pros**

1. **Improved Performance and Shift Quality**

The 60304 is a high-performance version of the classic TH350 transmission, featuring a stronger torque converter and upgraded internal components. This results in quicker, smoother shifts and better acceleration, especially under heavy loads or when towing.

2. **Higher Torque Capacity**

The stock TH350 transmission is rated for around **300 350 lb-ft of torque**, while the 60304 is designed to handle **up to 400 450 lb-ft** with proper modifications. This makes it a better fit for modified engines or trucks with aftermarket power upgrades.

3. **Durability and Longevity**

The 60304 is built with stronger clutch packs, bearings, and shafts compared to the stock unit. Many users report longer service intervals and reduced wear, particularly in high-stress applications like towing or hauling.

4. **Compatibility with Aftermarket Upgrades**

- **Performance torque converters** (e.g., Carter, Muncie, or Hurst)

- **Upgraded flywheel/dual-mass flywheel (DMF)**

- **Performance fluid (e.g., Mopar ATF 4, Valvoline MaxLife, or Lucas Oil)**

- **Shift solenoids and transmission coolers** for better heat management

5. **Better Heat Dissipation**

The 60304 s internal design allows for improved fluid circulation, reducing the risk of overheating in demanding applications. Pairing it with a transmission cooler is highly recommended for heavy-duty use.

6. **Widely Available and Affordable**

Compared to some high-end transmissions (e.g., Tremec T56 or Allison), the 60304 remains relatively inexpensive, with prices typically ranging from **$800 $1,500** depending on the seller and included components (e.g., gasket set, shift kit).

7. **Proven Reliability in Older Chevys**

The TH350 platform has been used in Chevrolet trucks for decades, and the 60304 builds on that legacy. Many owners of **C/K trucks (1994 2007), Silverado 1500 (pre-2007), and GMC Sierra** report success with this upgrade.

8. **Easier Installation**

Since it s a direct drop-in replacement, installation is straightforward for those with basic mechanical skills. Most shops can install it in **4 6 hours**, and it doesn t require major drivetrain modifications.

9. **Supports Towing and Hauling**

When paired with a **performance torque converter, cooler, and proper fluid**, the 60304 can handle **light to moderate towing (up to 5,000 7,000 lbs)** without excessive stress, depending on the vehicle s setup.

10. **Aftermarket Support**

There is a strong aftermarket presence for the TH350, meaning parts like **solenoids, seals, and rebuild kits** are readily available. This makes maintenance and repairs more accessible.

---

### **Cons**

1. **Still a 3-Speed Transmission**

- **Higher RPMs at highway speeds**, leading to increased wear on the engine and drivetrain.

- **Reduced fuel efficiency** compared to a 4-speed or 5-speed automatic.

- **Limited towing capability** in high-gear scenarios (e.g., long-distance towing at 60 mph).

2. **Requires Additional Modifications for Full Performance**

While the 60304 is stronger than the stock unit, it is **not a "drop-in" performance transmission** without extra upgrades. To get the most out of it, you ll likely need:

- A **performance torque converter** (stock converters are weak for high-torque applications).

- A **transmission cooler** (critical for towing or heavy loads).

- **Upgraded fluid** (stock fluid is not sufficient for high-performance use).

- Possibly a **dual-mass flywheel** (if the stock flywheel is worn).

These additional costs can add **$500 $1,500 ** to the total upgrade.

3. **Not Ideal for Extreme Power or Heavy Towing**

While the 60304 can handle **up to 450 lb-ft of torque** with modifications, it is **not designed for extreme power** (e.g., **600 lb-ft** from a big-block engine or forced induction). In such cases, a **heavy-duty transmission like the Tremec T56 or a custom-built unit** may be necessary.

4. **Shift Solenoid Issues**

Some users report **shift solenoid failures** over time, especially if the transmission is not properly cooled or maintained. Replacing solenoids can add to long-term costs.

5. **Limited Modern Compatibility**

The 60304 is **not compatible with newer Chevrolet trucks (post-2007)** without significant modifications, as wiring and control modules have changed. It is best suited for **pre-2007 models**.

6. **Potential for Overheating Without a Cooler**

The TH350 platform is **prone to overheating** under heavy loads. Without a **transmission cooler**, the fluid can break down prematurely, leading to **slipping, rough shifts, or failure**.

7. **Not a "Set-and-Forget" Upgrade**

- **Fluid changes every 30,000 50,000 miles** (or more frequently for towing).

- **Inspection of seals, bushings, and solenoids** during rebuilds.

- **Proper cooling system maintenance** (radiator, cooler, and hoses).

8. **Possible Reverse Gear Wear**

Some owners report **reverse gear wear** over time, leading to **grinding or slipping in reverse**. This is often due to **lack of lubrication** or **misalignment** during installation.

9. **Not a "Future-Proof" Transmission**

If you plan to keep the truck long-term, a **modern 4-speed or 5-speed automatic** (e.g., **6L80, 6L90, or Allison**) may be a better long-term investment, despite higher upfront costs.

10. **Installation Risks if Not Done Properly**

While the 60304 is a direct swap, **incorrect installation** (e.g., misaligned shafts, improper gasket sealing, or loose bolts) can lead to **premature failure**. This makes **professional installation highly recommended** for first-time builders.

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### **Conclusion**

The **60304 GM TH350 Performance Automatic Transmission** is an **excellent upgrade** for **pre-2007 Chevrolet 2WD trucks** looking to improve shift quality, torque handling, and overall durability **especially for those engaged in light towing, hauling, or performance modifications**. It offers a **cost-effective way to enhance an older transmission** without requiring a full rebuild or a major drivetrain overhaul.

However, it is **not a "magic bullet"** it still has **limitations as a 3-speed transmission**, and **additional modifications (torque converter, cooler, fluid) are necessary** to unlock its full potential. If you plan to **push the truck hard with high torque or heavy towing**, you may need to invest in further upgrades to prevent overheating and wear.

For **casual drivers, light haulers, or those running stock or mildly modified engines**, the 60304 is a **solid choice** that provides noticeable improvements over the stock unit. For **extreme power applications or long-term reliability**, a **modern transmission or a custom-built unit** may be worth considering.

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### **Final Recommendation**

You own a **pre-2007 Chevrolet 2WD truck** (e.g., C/K, Silverado 1500, GMC Sierra).

You want **smoother shifts, better torque handling, and improved durability** without a full rebuild.

You plan to **tow lightly (up to 5,000 7,000 lbs) or haul moderate loads**.

You are willing to **invest in additional upgrades** (performance torque converter, cooler, proper fluid).

You prefer a **proven, budget

Details:

part #: 60304 price

• $2404.99

specifications autotransmissionsgo:

• for models: 2wd
• for makes: Chevrolet
• brand: Jegs
• mpn: 60304
• part type: Transmission
• country of origin: Usa
• upc: 889944256533

payments autotransmissionsgo:

• credit card: Diners-club
• wallet: Apple-pay
• other

offer autotransmissionsgo:

• options: Ship-to-home
• quantity: 10
• sold: 0
• started: May 10, 2026
• availability: In Stock

seller autotransmissionsgo:

• city: , Ohio
• # reviews: 629226
• rating: 99.4%

general autotransmissionsgo:

• condition: New
• Car Truck Parts Accessories > Transmission Drivetrain > Automatic Transmission

returns autotransmissionsgo:

• paid by: Seller
• policy: Returns Accepted
• time: 30 Days

shipping autotransmissionsgo:

• class: Standard
• transit: 5-11 Days
• cost: $0.00
• type: Fixed
• service: Standard

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