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03 Bravada AWD clunk


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Posted

I have a 03 Bravada AWD and I have noticed a "clunk" sometimes during acceleration from a stop. The clunk can be felt in the steering wheel, most noticeably during heavy acceleration and it clunks a few times. I can also feel/hear this "clunk" under normal driving conditions when going up a hill. I had the steering wheel binding and chutter TSB fixed after a few thousand miles and was wondering if maybe the two problems were related? Any tech info on my "clunk" problem is greatly appreciated.

 

Also, how does the smarttrak work? When is the vehicle in 4x4? Is it just when it needs it or whenever it is under 35mph? I was told many different things about how it works, anyone know for sure?

Posted

I'm not aware of any clunking issues like you describe. Without experiencing it, I couldn't even guess what it might be.

 

As for your 4wd system, it's full-time all wheel drive. Here's the "official" description of its operation, though it might be a little technical.

 

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The New Venture Gear model NVG 126 RPO NP4 transfer case is a one speed automatic, active, transfer case. The NVG 126 provides only one mode, Auto 4WD, and is transparent to the operator. The active transfer case provides the benefits of on-demand torque biasing, wet clutch and easy vehicle tuning through software calibrations. The software calibrations allow more features, such as flexible adapt ready position and clutch pre-load torque levels. The technology allows for vehicle speed dependent clutch torque levels to enhance the performance of the system. For example, the system is calibrated to provide 0-7 N·m (0-62 lb in) of clutch torque during low speed, low engine torque operation, and predetermined higher torque for 32 km/h (20 mph) and greater. This prevents crow-hop and binding at low speeds, and provides higher torque biases at higher vehicle speeds, to enhance stability.

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