Unbolting The 700R4 Transmission: Oil Pan Bolt Count

The 700R4 transmission from General Motors is a reliable and sought-after automatic gearbox. It features four forward gears and reverse, and is used in all types of cars and trucks. The 700R4 has a 16-bolt oil pan. The factory bolts are M8 1.25x19.3, and there are 16 bolts and 16 washers in a standard kit.

GM 700R4 transmission pan bolt kit includes 16 bolts and 16 washers

The GM 700R4 transmission pan bolt kit is a zinc-plated transmission pan allen head bolt kit. It is designed for use with GM 700R4 transmission pans with the part numbers HZ-7599, HZ-9712, and HZ-8493kit. The kit includes 16 zinc-plated steel bolts and 16 zinc-plated washers. The bolt size is 8M-1.25.

This bolt kit is compatible with several GM and Chevy transmissions, including the 4L60, 4L60e, 2004R, 700R4, and 200R4. It is also compatible with specific engines, such as the LS1, LM7, LR4, LQ4, LS6, L59, LQ9, LM4, L33, SBC 305, 327, 350, and 383. The bolts are grade 10.9, JIS head, and have a length of 16mm.

The GM 700R4 transmission pan bolt kit provides high-quality and affordable solutions for those undertaking an LS swap project. The bolts are clear zinc-coated steel, ensuring corrosion protection and preventing thread seizing. Additionally, the kit's bolts have a larger head size compared to stock bolts, providing a clean and tight fit.

This bolt kit offers a hassle-free installation process, ensuring a secure and leak-free transmission pan. It is essential to follow the torque specifications for the 700-R4 transmission pan bolts to achieve optimal results. Proper torque settings and careful inspection of the pan and mounting surfaces are crucial steps to prevent leaks and ensure the longevity of the transmission.

The factory bolts are M8 1.25x19.3

The M8 1.25x19.3 bolts are often used in transmission pan bolt kits for vehicles such as the Chevy/GM 700R4 and similar models. These kits typically include 16 bolts and matching washers. When purchasing replacement bolts, it is important to ensure that the correct size and grade are selected to guarantee compatibility and maintain the integrity of the transmission system.

The installation process for these bolts typically involves using a torque wrench to achieve the recommended torque specification of 9 ft-lbs. Proper torque ensures a secure fit and helps prevent leaks. It is also crucial to inspect the transmission pan for any warping or distortion before installation, as this can lead to leaks even with properly tightened bolts.

Additionally, the M8 1.25x19.3 bolts can be purchased from various retailers, including Amazon and Home Depot, either individually or in packs of varying quantities. When buying bolts, it is advisable to check the product specifications and reviews to ensure their suitability for your specific application.

GM 700R4 transmission is reliable and sought-after

The GM 700R4 transmission is a reliable and sought-after four-speed automatic gearbox, even over 40 years after its introduction. Its popularity is due to its strength, compact nature, and fuel efficiency.

The 700R4 was first introduced in the early 1980s as an upgrade to the three-speed TH350 automatic transmission. The 700R4 features a 30% overdrive ratio of 0.69:1, which was a notable improvement over the TH350's direct-drive third gear. This allowed the 700R4 to keep rpm down while cruising and still perform well off the line. The 3.06:1 first gear ratio was also popular with off-road enthusiasts.

The 700R4 transmission is made from cast aluminium, which adds to its sturdiness and ruggedness. It is 23.4 inches long, weighs 155 pounds, and has 16 bolts. The transmission can store about 11 quarts of transmission fluid, and its recommended fluid is Dexron VI.

The 700R4 transmission was used in a wide range of vehicles between 1982 and 1993, including trucks and rear-wheel-drive cars such as the Astro Van, S10 Blazer, Pontiac Firebird, and Holden Commodore. The widespread use of the 700R4 continued until 1992, with the 1993 Corvette, Camaro, and Typhoon being the last vehicles to feature the transmission.

The 700R4 has undergone several updates and improvements throughout its lifespan. In 1984, the 27-spline input shaft, which was a known point of failure, was replaced with a 30-spline shaft. Internal components such as the oil pump housing and ring gear were also updated between 1984 and 1987. In 1986, an auxiliary valve body was added for smoother shifting.

Despite some common issues such as overheating and a prone-to-fail input shaft, the 700R4 is considered a reliable and durable transmission. It is also easy to find replacement parts due to its popularity. Overall, the GM 700R4 transmission is a sought-after option for those looking for a sturdy and fuel-efficient gearbox.

Torque the bolts to 12 foot-pounds

Torque is a twisting force that measures force multiplied by distance. It is the application of force acting at a radial distance to create tension in threaded fasteners. When tightening bolts, it is important to ensure that the bolt has the appropriate amount of torque and tension to avoid bolt shearing and tensile forces.

The torque for a 700-R4 transmission pan bolt should be set to 12 foot-pounds. This can be achieved by using a torque wrench, which will allow you to measure and apply the proper torque. However, it is important to note that torque wrenches are not perfectly accurate, so it is recommended to double-check the torque value using one of the following methods:

• The First Movement Test: After tightening the fastener, use a torque audit wrench to slowly apply force in the tightening direction until you notice the first movement in the fastener. The reading will indicate the original torque applied.
• Reverse First Movement Test: This is the same as the first method, but in the opposite direction. Apply force in the loosening direction until you feel the first movement, and the reading on the audit wrench will indicate the torque.
• Mark Alignment Method: Mark the surface of the fastener and the surface it is being fastened to. Then, loosen the fastener, wait a moment, and re-tighten until the marks align. The torque required to reach this point is a reference for the original torque used.

By following these instructions and torqueing the bolts to 12 foot-pounds, you can ensure a secure and functional bolt tightening process for the 700-R4 transmission pan.

The 700R4 transmission has a 30-spline input shaft

The 700R4 transmission, a popular General Motors transmission, is known for its propensity to leak around the pan due to distorted mounting bolt holes or warping of the pan caused by improper installation. To address this issue, it is crucial to ensure that the pan is properly inspected and repaired before setting the pan bolts to the recommended torque of 12 foot-pounds.

Now, let's delve into the specific topic of the 700R4 transmission's 30-spline input shaft:

The 30-spline input shaft provides a stronger and more durable connection between the torque converter and the transmission. This enhancement not only improves performance but also contributes to the overall longevity of the transmission. It is worth noting that when dealing with the 700R4 transmission, it is important to determine whether it has a 30-spline or 27-spline count to ensure the correct matching of components, especially when purchasing a new torque converter.

The upgrade to a 30-spline input shaft was one of the significant improvements made by GM to enhance the reliability of the 700R4 transmission. This particular upgrade addressed a common failure point, ensuring that the transmission could handle higher torque and perform more efficiently. As a result, the 700R4 transmission with the 30-spline input shaft became a popular choice for high-performance applications and contributed to its reputation as a rugged and dependable transmission option.

In summary, the 700R4 transmission's 30-spline input shaft is a crucial feature that enhances the transmission's overall performance and durability. This upgrade addressed previous shortcomings, making the 700R4 transmission a preferred choice for those seeking a robust and reliable transmission system, especially when paired with small-block Chevy V-8 engines.

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