Introduction
This manual provides essential instructions for the proper installation, operation, and maintenance of your PROFORM 66182 TH400 Locking Dipstick and Tube. Please read this manual thoroughly before installation and use to ensure optimal performance and safety.

Image 1: PROFORM 66182 TH400 Locking Dipstick and Tube. This image displays the complete dipstick and tube assembly, showcasing its black finish and overall design.
Setup and Installation
The PROFORM 66182 is designed for TH400 transmissions and features a bellhousing mount. Proper installation is crucial for accurate fluid level readings and to prevent leaks.
- Verify Compatibility: Ensure this dipstick and tube assembly is compatible with your specific vehicle and TH400 transmission model. Refer to your vehicle's service manual for transmission specifications.
- Prepare for Installation: Ensure the transmission is cool. Clean the area around the transmission dipstick opening to prevent contaminants from entering the transmission.
- Install the Tube: Carefully insert the dipstick tube into the designated opening on the transmission. The bellhousing mount should align correctly. Secure the tube according to standard automotive practices, ensuring a tight seal.
- Insert the Dipstick: Insert the locking dipstick into the newly installed tube. Ensure it seats fully and the locking mechanism engages securely.
- Initial Fluid Level Check: After installation, start the vehicle and allow the transmission to reach operating temperature. Follow the operating instructions to check the fluid level. Add or remove fluid as necessary to achieve the correct level.
Important: Incorrect installation can lead to fluid leaks or inaccurate fluid level readings, potentially causing transmission damage. If you are unsure about the installation process, consult a qualified automotive technician.
Operating Instructions
This locking dipstick is designed to provide a secure seal and accurate transmission fluid level readings.
- Checking Fluid Level:
- Ensure the vehicle is on a level surface and the engine is at operating temperature.
- With the engine running and the transmission in Park (P) or Neutral (N) as specified by your vehicle manufacturer, locate the dipstick.
- To unlock, rotate the dipstick handle as indicated by the "TRANS/LOCK" marking, then pull it out slowly.
- Wipe the dipstick clean with a lint-free cloth.
- Reinsert the dipstick fully until the locking mechanism engages.
- Remove the dipstick again and observe the fluid level. The fluid should be between the "FULL" and "ADD" marks.
- If fluid is low, add the recommended type of transmission fluid in small increments, rechecking the level after each addition.
- Once the correct level is achieved, reinsert the dipstick and ensure it is securely locked to prevent fluid loss and contamination.

Image 2: Close-up of the dipstick handle, showing the "TRANS/LOCK" marking and the locking mechanism. This indicates how to engage and disengage the lock.
Maintenance
Regular maintenance ensures the longevity and proper function of your PROFORM locking dipstick and tube.
- Cleaning: Periodically clean the exterior of the dipstick and tube to remove dirt, grime, and oil residue. Use a mild automotive cleaner and a soft cloth. Avoid harsh chemicals that could damage the finish or seals.
- Seal Inspection: Inspect the O-rings or seals on the dipstick and tube for any signs of wear, cracking, or damage. Damaged seals can lead to leaks. Replace seals if necessary.
- Locking Mechanism Check: Ensure the locking mechanism operates smoothly and securely engages when the dipstick is fully inserted. If it feels loose or does not lock properly, inspect for debris or damage.
- Material: The dipstick and tube are constructed from alloy steel, providing durability.
Troubleshooting
- Difficulty Removing Dipstick: If the dipstick is difficult to remove, ensure the locking mechanism is fully disengaged. Check for any bends or obstructions in the tube. Applying a small amount of transmission fluid to the O-rings can aid in removal and reinsertion.
- Inaccurate Fluid Readings: Ensure the vehicle is on a level surface and the engine is at operating temperature when checking fluid. Verify that the dipstick is fully inserted and locked. If readings remain inconsistent, inspect the tube for damage or kinks.
- Fluid Leaks: Check the seals and O-rings on both the dipstick and the tube for proper seating and damage. Ensure the tube is securely mounted to the transmission.
- Fitment Issues: If the dipstick or tube does not fit correctly, double-check the product's compatibility with your specific TH400 transmission and vehicle model. Incorrect application can lead to fitment problems.
For issues not resolved by these steps, it is recommended to consult a professional automotive technician.
Specifications
| Feature | Detail |
|---|---|
| Model Number | 66182 |
| Brand | ProForm |
| Product Type | Transmission Dipstick and Tube |
| Transmission Compatibility | TH400 |
| Mounting Type | Bellhousing Mount |
| Material | Alloy Steel |
| Item Dimensions (L x W x H) | 25.8 x 6.8 x 3 inches |
| Item Weight | 1 pound (16 ounces) |
| UPC | 037995661824 |
Warranty and Support
For specific warranty information, please refer to the documentation provided with your purchase or contact ProForm customer support directly. Keep your proof of purchase for any warranty claims.
Customer Support: For technical assistance or inquiries regarding this product, please visit the official ProForm website or contact their customer service department.
California Proposition 65 Warning: This product may expose you to chemicals known to the State of California to cause cancer and reproductive harm. For more information, visit www.P65Warnings.ca.gov.





