The Dana 35 TruTrac is an open differential upgrade designed to deliver more predictable traction compared to a traditional open differential. By using a clutch-based mechanism, it helps both rear wheels receive power when one wheel loses grip, which is especially useful on uneven surfaces or during light off-road driving.
Engine enthusiasts and daily drivers use this component to improve straight-line stability and cornering consistency without the locking behavior of a limited slip or fully locked differential. Understanding its internal design, installation requirements, and long-term maintenance expectations helps owners decide whether it fits their driving needs.
Dana 35 TruTrac at a Glance
| Model | Dana 35 Stock | Dana 35 with TruTrac | Dana 44 Comparison |
|---|---|---|---|
| Differential Type | Open | Clutch-Type Limited Slip | Often Open or Detroit Locker Option |
| Street Traction | Poor on low grip | Improved for daily driving | Higher overall grip |
| Off Road Capability | Limited slip in low traction | Better than open, not fully locked | Higher durability for serious trails |
| Maintenance Level | Standard open differential service | Requires clutch-friendly fluid | More frequent seal checks recommended |
| Typical Use Case | Commuting, light towing | All weather, light off road | Heavy off road, rock crawling |
How the TruTrac Mechanism Works
Inside the Dana 35 TruTrac, a set of helical gears and friction clutches automatically engages both side gears when wheel slip is detected. This action distributes torque to the wheel with more grip, reducing the spinning behavior of a fully open differential. Unlike locker-style differentials, it never fully locks, which keeps turning smooth on pavement and reduces drivetrain bind on uneven terrain.
Advantages Over Open Differentials
By reacting to traction loss, the TruTrac reduces the need for driver correction on wet roads, gravel, or snow. Many owners notice fewer abrupt corrections and a steadier feel during acceleration, especially with moderate loads. The system remains passive during straight line driving and activates mostly when one wheel is on a slippery surface.
Performance Limitations to Consider
Because the clutch packs are always in light contact, there may be slight wear over very high mileage. The unit is not intended for high torque drag racing or constant heavy off road wheel spin, where a gear style locker or stronger gear set would be more appropriate. Understanding these limits helps set realistic expectations for everyday use.
Installation and Fitment Guidelines
Swapping a standard Dana 35 for a TruTrac model typically requires only a differential replacement, but some vehicles may benefit from additional alignment or brake component checks. Proper installation includes using the correct lubricant, setting backlash within spec, and ensuring universal joints or axle shafts rotate freely without binding. Following the manufacturer recommended bedding procedure allows the clutch packs to seat correctly for reliable performance.
Required Tools and Preparation
Most installations need a bearing puller, torque wrench, and new seals to prevent leaks. Draining the gear oil, cleaning magnet surfaces, and inspecting for metal particles can prevent future surprises. Taking time to verify axle shaft splines and yoke wear helps avoid vibration or noise after the swap.
Everyday Driving and Maintenance Tips
Drivers often report improved confidence during rain, light snow, or gravel, without the harsh engagement of older limited slip designs. Routine fluid changes using a manufacturer approved gear lube help extend clutch life and reduce whining. Keeping an eye on driveline noises and checking for leaks after service ensures the Dana 35 TruTrac continues delivering predictable traction over the long term.
Long Term Ownership and Value
For owners who prioritize predictable handling and occasional light off road use, the Dana 35 TruTrac offers a balanced compromise between open simplicity and limited slip performance. Regular maintenance, proper fluid selection, and avoiding extreme wheel spin help preserve clutch life and reduce unexpected repairs.
- Use manufacturer recommended gear lube for clutch compatibility
- Inspect for unusual noise or vibration after installation
- Avoid constant high speed aggressive cornering to reduce wear
- Monitor fluid condition during routine service intervals
- Consider axle and driveline alignment when replacing components
FAQ
Reader questions
Does the Dana 35 TruTrac lock completely like a locker?
No, it remains an open style differential with clutch assistance, so it never fully locks and always allows some difference in wheel speed for smoother cornering.
Is it suitable for daily driving in all weather conditions?
Yes, it is designed for street and light off road use, offering better traction than a standard open in rain, snow, or gravel without excessive drivetrain noise.
Will installing this improve my fuel economy?
There is usually no significant fuel economy gain, and in some cases a slight decrease may occur due to internal friction, but the main benefit is traction and stability.
What fluid should I use during service?
Follow the vehicle or differential manufacturer recommendation, typically a hypoid or gear lube approved for clutch type limited slip applications to prevent premature wear.