The Turbo Hydra-Matic 400, often referred to as the TH400, is a legendary automatic transmission known for its robustness and reliability. Favored by drag racers, off-road enthusiasts, and muscle car aficionados, it has earned its place in automotive history. One common question that arises when dealing with this transmission is: how much does a TH400 weigh? This article will delve deep into the weight specifics of a TH400, exploring factors that influence its weight and comparing it to other popular transmissions.
Understanding the Base Weight of a TH400 Transmission
The base weight of a TH400 transmission typically falls between 130 to 135 pounds. This refers to the weight of the transmission itself, without any fluids, torque converter, or external accessories. It’s a substantial piece of machinery, reflecting its heavy-duty construction.
The TH400’s robust design contributes to its considerable weight. It features a cast-iron case, heavy-duty gears, and a large torque converter. These components are built to withstand high horsepower and torque, making it a popular choice for performance applications.
Keep in mind that this base weight serves as a general guideline. Variations can occur depending on the specific year, manufacturer, and any modifications that may have been made to the transmission.
Factors Influencing the Weight of a TH400
Several factors can affect the overall weight of a TH400 transmission. It’s crucial to consider these variables when estimating the total weight for shipping, installation, or performance calculations.
Fluid Fill
The TH400 requires transmission fluid to operate properly. The amount of fluid it holds will significantly impact its overall weight. A fully filled TH400 can weigh considerably more than its dry weight.
The TH400 typically holds around 10 to 12 quarts of transmission fluid. Transmission fluid weighs approximately 7 pounds per gallon, so this adds a significant amount of weight.
Torque Converter
The torque converter is a crucial component that connects the engine to the transmission. It acts as a fluid coupling, allowing the engine to continue running even when the transmission is stopped.
Torque converters for the TH400 come in various sizes and designs, each with a different weight. A typical torque converter for a TH400 can weigh between 30 and 50 pounds, depending on its size and construction.
The weight of the torque converter is a significant factor when calculating the total weight of the TH400 assembly. Performance-oriented torque converters, designed for higher stall speeds and increased torque multiplication, often weigh more than stock converters.
Transmission Adapter Plates and Bellhousings
Depending on the application, a TH400 may require adapter plates or a different bellhousing to mate with a specific engine. These adapters and bellhousings add to the overall weight.
The weight of adapter plates and bellhousings can vary depending on the material and design. Aluminum adapters are lighter than steel adapters, but steel offers greater strength.
External Accessories and Modifications
External accessories, such as transmission coolers, dipstick tubes, and aftermarket shifters, also contribute to the overall weight of the TH400 assembly.
Aftermarket modifications, such as valve body upgrades or hardened shafts, may also add a small amount of weight. These modifications are often done to improve performance and durability.
Casting Variations
Even within the same model year, slight variations in the casting process can lead to minor weight differences between individual TH400 transmissions. These differences are usually negligible but can exist.
Estimating the Total Weight of a TH400 Transmission
To accurately estimate the total weight of a TH400 transmission, you need to consider the base weight, the weight of the torque converter, the weight of the fluid, and the weight of any adapters or accessories.
Here’s a breakdown of how to calculate the estimated weight:
- Base Transmission Weight: 130-135 pounds
- Torque Converter Weight: 30-50 pounds
- Fluid Weight: (10-12 quarts / 4 quarts per gallon) * 7 pounds per gallon = 17.5-21 pounds
- Adapter Plate/Bellhousing Weight: Varies depending on material and design (estimate 5-15 pounds)
- External Accessories: Varies depending on accessories (estimate 2-5 pounds)
Adding these weights together, the total estimated weight of a TH400 transmission, ready to install, is approximately 184.5 to 226 pounds. This is a significant weight, so proper lifting equipment and safety precautions are essential when handling a TH400.
Comparing the Weight of a TH400 to Other Transmissions
Understanding how the weight of a TH400 compares to other popular transmissions can help you make informed decisions about your drivetrain setup.
TH350 vs. TH400
The TH350 is another popular automatic transmission from General Motors. It is lighter than the TH400, making it a more suitable option for applications where weight is a critical concern.
A TH350 typically weighs around 120 pounds dry, which is 10-15 pounds lighter than a TH400. However, the TH400 is significantly stronger and more durable than the TH350.
4L60E vs. TH400
The 4L60E is an electronically controlled automatic transmission that replaced the TH350 in many GM vehicles. It is lighter than the TH400 and offers the advantage of overdrive.
A 4L60E typically weighs around 140 pounds dry. While it offers an overdrive gear for improved fuel economy, it is generally not as strong as the TH400.
Ford C6 vs. TH400
The Ford C6 is a heavy-duty automatic transmission similar to the TH400. It was commonly used in Ford trucks and performance cars.
The Ford C6 weighs approximately 165 pounds dry, making it heavier than the TH400. Both transmissions are known for their durability and strength.
Why the Weight Matters
The weight of a TH400 transmission is a crucial consideration for several reasons.
Performance
Weight directly affects vehicle performance. A heavier transmission can reduce acceleration, braking, and handling. In racing applications, every pound counts. While the TH400 provides strength, its weight can be a disadvantage in some scenarios.
Shipping and Handling
Shipping a TH400 can be expensive due to its weight. The cost of shipping increases with weight, so it’s essential to get an accurate weight estimate before arranging shipment.
Handling a TH400 requires proper lifting equipment and safety precautions. Its weight makes it difficult to move and install without the right tools.
Installation
Installing a TH400 can be challenging due to its weight. It requires a transmission jack or other lifting device to safely lift and position the transmission. Working with a heavy transmission can be dangerous if proper safety measures are not followed.
Conclusion
The TH400 is a robust and reliable transmission with a base weight of approximately 130-135 pounds. However, the total weight can range from 184.5 to 226 pounds when including fluid, torque converter, and accessories. This weight is an important factor to consider for performance, shipping, handling, and installation purposes. While its weight might be a drawback in certain applications, the TH400’s strength and durability make it a popular choice for high-performance vehicles and demanding applications. Understanding the factors that contribute to the weight of a TH400 allows you to make informed decisions and plan accordingly when working with this legendary transmission.
What is the approximate weight of a bare TH400 transmission?
The weight of a bare TH400 transmission, meaning the transmission without any fluid, torque converter, or external components like the bellhousing or tailshaft housing, is typically around 130 to 135 pounds. This weight can vary slightly depending on the specific manufacturer, the year it was produced, and any internal modifications that might have been made.
Keep in mind that this is just the weight of the core transmission itself. To get a true understanding of the total weight you’ll be dealing with when installing or transporting a TH400, you’ll need to factor in the additional weight of the torque converter, transmission fluid, bellhousing, tailshaft housing, and any other accessories attached to it.
How much does a TH400 weigh with fluid and a torque converter?
When filled with transmission fluid and equipped with a standard torque converter, a TH400 transmission’s weight increases significantly. You can generally expect the total weight to be somewhere in the neighborhood of 170 to 180 pounds. This added weight is mainly due to the fluid capacity of the transmission and the substantial mass of the torque converter.
The specific type of torque converter used can influence this final weight, as larger, high-performance converters will naturally be heavier than smaller, stock units. Similarly, the amount of fluid required will depend on the specific pan and cooler lines installed, adding further variability. Always account for these additions when planning installations or transportation.
Does the bellhousing material affect the overall weight of a TH400?
Yes, the material of the bellhousing does have an impact on the overall weight of the TH400 transmission assembly. Bellhousings are commonly made from either cast iron or aluminum. Cast iron bellhousings are significantly heavier than their aluminum counterparts.
Choosing an aluminum bellhousing can shave several pounds off the total weight of the transmission. This weight difference can be a consideration for performance applications where reducing weight is a priority. However, cast iron bellhousings are often preferred for their increased strength and durability, especially in high-horsepower applications.
How does the tailshaft housing affect the TH400’s weight?
The tailshaft housing is another component that contributes to the total weight of a TH400 transmission, though typically less than the bellhousing. The material of the tailshaft housing, usually cast iron or aluminum, and its length will impact the final weight. Longer tailshaft housings, designed for specific vehicle applications, will naturally be heavier than shorter ones.
While the weight difference between cast iron and aluminum tailshaft housings might not be as dramatic as with bellhousings, it’s still a factor, particularly when combined with other weight-saving measures. Swapping to an aluminum tailshaft housing can contribute to a minor reduction in overall weight, although the primary consideration is typically based on the required length and mounting configuration for the specific vehicle application.
Why is the TH400 considered a heavy-duty transmission?
The TH400 is considered a heavy-duty transmission due to its robust internal components and overall design. It features a strong cast iron case, a large 32-spline output shaft, and a heavy-duty planetary gear set. These components are designed to withstand high horsepower and torque levels, making it a popular choice for performance and racing applications.
Furthermore, the TH400’s simple and reliable design contributes to its durability. It’s known for its ability to handle significant abuse, making it a preferred option for trucks, SUVs, and high-performance vehicles where reliability and strength are paramount. The robust construction allows it to handle the stresses associated with towing, off-roading, and drag racing far better than many lighter-duty transmissions.
Is the weight of a TH400 significantly different from other automatic transmissions?
Yes, the weight of a TH400 is typically greater than many other common automatic transmissions, particularly those found in smaller or more modern vehicles. Transmissions like the TH350, 700R4, or newer electronic transmissions are often designed with weight reduction in mind, utilizing lighter materials and smaller overall dimensions.
The TH400’s heavier construction is a direct result of its heavy-duty design. While the increased weight might be a disadvantage in some situations where weight savings are crucial, it’s a trade-off for the transmission’s inherent strength and durability. This makes it a more suitable option for applications where high power handling and longevity are prioritized over minimizing weight.
What are some strategies to reduce the weight of a TH400 transmission setup?
Several strategies can be employed to reduce the weight of a TH400 transmission setup, though some may come at a higher cost or potentially compromise strength. The most common approach is to use an aluminum bellhousing and tailshaft housing instead of cast iron versions. This can save a noticeable amount of weight without significantly affecting the transmission’s performance in many applications.
Additionally, using a smaller, lighter torque converter can contribute to weight reduction. Careful selection of ancillary components, such as lightweight transmission pans and cooler lines, can also provide marginal weight savings. Ultimately, the decision to implement these strategies should be based on the specific needs of the application and the desired balance between weight savings and overall strength and reliability.