how to build a bulletproof 4r70w

Building a bulletproof 4R70W transmission involves a series of modifications and upgrades to enhance its strength and durability. The 4R70W is a popular automatic transmission used in many Ford vehicles, and making it “bulletproof” typically means reinforcing it for high-performance applications or heavy-duty use. Here are the steps to build a bulletproof 4R70W:

  1. Assessment and Inspection:
    • Start by thoroughly inspecting the existing transmission to identify any worn or damaged components. This includes checking the torque converter, clutches, bands, and seals.
  2. Select Quality Parts:
    • Invest in high-quality aftermarket or performance parts that are designed to handle increased power and torque. Look for reputable manufacturers who specialize in transmission components.
  3. Rebuild the Transmission:
    • Disassemble the transmission and replace any worn or damaged parts. This may include upgrading the clutches, bands, and torque converter to heavy-duty or performance versions.
  4. Strengthen the Gear Train:
    • Upgrade the planetary gear set to a stronger one, such as a billet or aftermarket planetary gear set. This can help handle higher horsepower and torque levels.
  5. Install a Shift Kit:
    • Install a shift kit to improve shift performance and reduce slippage. This will also allow you to adjust shift firmness to your preference.
  6. Upgrade the Valve Body:
    • Consider installing an aftermarket or performance valve body to improve hydraulic control and increase overall transmission performance.
  7. Add a Transmission Cooler:
    • Install a high-capacity transmission cooler to help keep the transmission fluid at an optimal temperature, especially if you plan to use the vehicle for towing or high-performance driving.
  8. Modify the Pump:
    • Some builders choose to modify the transmission pump to increase fluid pressure for improved clutch engagement. This is particularly important for high-performance applications.
  9. Install a Deep Transmission Pan:
    • A deep transmission pan with cooling fins can help dissipate heat more effectively and provide extra fluid capacity.
  10. Reinforce the Case and Shafts:
    • Depending on your power goals, consider reinforcing the transmission case and upgrading to hardened input and output shafts for added strength.
  11. Adjust the Transmission Control Strategy:
    • If your vehicle has a computer-controlled transmission, you may need to reprogram or tune the transmission control module (TCM) to accommodate the upgrades and optimize shift points.
  12. Dynamometer Testing:
    • After the rebuild and modifications, it’s essential to perform dyno testing to ensure the transmission is performing as expected and handling the increased power and torque.
  13. Regular Maintenance:
    • Proper maintenance is key to keeping your bulletproof 4R70W transmission in top condition. Regularly change the transmission fluid and filter, and monitor for any signs of wear or issues.

Building a bulletproof 4R70W transmission requires knowledge of transmission rebuilding and modification techniques. It’s often a good idea to consult with a transmission specialist or a reputable transmission shop with experience in high-performance builds to ensure the best results. Additionally, consider your specific performance goals and budget when selecting components and upgrades.

Related Articles

Leave a Reply