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Cherry Bomb
There are all kinds of daily drivers: those called drivers because they have a few road miles on them, so they are not considered show cars; and those that are true daily drivers because they represent your only mode of transportation. Most rodders have been there at one time or another, when all we had were our hot rods to drive. The stories are endless about how these cars were transformed from grocery-getter to show car, but it happens. You use the car for family needs throughout the winter months and then clean it up come spring, maybe even paint the fenders, and enter it in a local rod show.

DASHING F100
In past stories we have shown you how to shave door handles, install custom outside door handles, round door corners, build suicide doors, add bear claw latches and so on. Now we’re going to offer you a personal favorite custom touch—installing a dash from a ’59-’60 Chevrolet Impala into a ’56 Ford F-100.

SNAKE CHARMER
If there is such a thing as an ’03 Cobra sleeper, and we’re not sure there is, this car could easily fill that vacancy. For those who know their Mustangs, the front fascia, hood and rear spoiler are all signs that this is not a car to underestimate. But the ’03 Cobra, mighty as it is, isn’t invincible. So, if you’re prowling the streets or the track in some modded Mach or souped SS, you might see this car and assume you’ve got something for it. You don’t—Ford Racing made sure of that, throwing practically its entire catalog at this car. But if you bought the best Mustang available, and it still isn’t enough for you, Ford Racing has something for you—and this car is living proof.
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PRODUCT SPOTLIGHT: Gearstar 4L65E Transmissions
Hand-Built for High-Performance
Author
The Auto Builder Staff
Photos Courtesy of Gearstar
Fits Like a Glove in Older Rides
Originally developed by GM as an upgrade to the 4L60E, the 4L65E was designed to meet the rising demands of performance vehicles. Though it looks nearly identical on the outside, it features internal enhancements—including a hardened input shaft, stronger sun shell, and a five-pinion rear planetary gear set. These enhancements make the 4L65E ideal for street performance, towing, or track use—easily handling more torque and heat than its predecessor.
Thanks to its two-piece case design and compact size, the 4L65E fits easily into most older vehicles without major modifications to the transmission tunnel. It’s a go-to option for hot rodders, classic car restorers, and custom builders alike.
Ideal for LS Engine Swaps
The 4L65E features a 7-bolt LS bellhousing pattern and a 13-pin main harness connector, making it highly compatible with modern GM engines and standalone transmission controllers. Whether your build is fuel injected or carbureted, Gearstar will configure your transmission to match your setup—including popular systems like Holley Sniper or Edelbrock Pro-Flo.
This level of adaptability has made the 4L65E one of the most popular transmissions for LS swap applications, especially for builds staying under the 650-horsepower mark.
Mopar-Compatible Transmission Option
For Mopar enthusiasts looking to modernize their drivetrain, Gearstar offers a version of the 4L60E/4L65E with a Mopar-specific bellhousing. Whether you’re running a Small Block, Big Block, or Gen III HEMI, this package includes a specially designed torque converter and requires a standalone controller—making it one of the few high-performance GM automatic transmissions available for Mopar engine applications.
Custom-Built, Not Mass-Produced
At Gearstar, every 4L65E is hand-built from start to finish by a single master technician. This hands-on approach ensures complete quality control and unmatched attention to detail. There are no assembly lines—just one expert dedicated to your build from the first bolt to final test.
Before shipping, each unit is dyno-tested for the equivalent of 100 miles. This rigorous process guarantees the transmission is performing flawlessly before it ever leaves the shop—saving you time and hassle during installation.
Perfectly Paired Torque Converter Included
Every Gearstar 4L65E package includes a custom torque converter, engineered specifically for your vehicle’s power level, application, and performance goals. Since acquiring Yank Performance Converters in 2022, Gearstar has brought converter manufacturing entirely in-house, ensuring seamless integration across the engine, transmission, and drivetrain.
Designed to Perform—Built to Last
Gearstar offers several performance levels for both 2WD and 4×4 applications. These range from Level II units rated for up to 400 horsepower to Level IV packages capable of handling 650 horsepower in 2WD or 600 in 4×4 configurations.
Level 2
Power Handling: 400 HP / 400 ft-lbs torque
Torque Converter Stall: Lower stall range (1600–2400 RPM) for smoother street driving
Component Strength: Uses high-energy frictions and a 10-vane pump, suitable for moderate builds
Performance Focus: Optimized for reliability and moderate performance
Level 3
Power Handling: 500 HP / 500 ft-lbs torque
Torque Converter Stall: Higher stall range (2600–3200 RPM) for performance
Component Strength: Upgrades to Raybestos Stage 1 frictions, a 13-vane pump, and a stronger input drum for increased durability
Performance Focus: Balances performance and durability for more demanding applications
Level 4
Power Handling: 650 HP / 600–650 ft-lbs torque
Torque Converter Stall: Highest stall range (2600–4000 RPM) with custom 10” or 11” billet converter for aggressive performance
Component Strength: Incorporates Raybestos Gen II racing frictions, hardened output and reaction shafts, and front/rear 5-pinion planetary sets for maximum strength
Performance Focus: Tailored for high-horsepower street and track use, with the most robust components
Additional Notes
- All levels require an ECU controller and transmission cooler for non-OEM applications.
- Gearstar’s transmissions are custom-built by a single technician and dyno-tested for reliability.
- The 4L65E’s design improvements (e.g., five-pinion planetary carrier, hardened sun shell, 300mm input shaft, and better 3-4 clutch) make it stronger than the 4L60E, with each level enhancing these features for higher performance.
Warranty and Support
Gearstar stands behind its craftsmanship:
- 2WD transmissions come with a 3-year / 36,000-mile warranty
- 4×4 transmissions include a 1-year / 12,000-mile warranty
Their in-house experts are always available to help with installation questions or performance tuning support—part of Gearstar’s commitment to long-term performance and customer satisfaction.
Upgrade with Confidence
The 4L65E represents more than just an evolution of the 4L60E—it’s a proven, high-performance transmission capable of supporting powerful street cars, off-roaders, and classic restorations alike. Built by experts. Dyno-tested. Backed by warranty. And ready to bolt in.
Ready to take your build to the next level? Gearstar has the performance you need—precision-built and track-tested.









