[Jacksont]

Hey there, ive had my 07 v6 awd for about a year now. Been a good car but for some reason the 4wd has never worked or worked properly. I have no engine lights or abs lights on. When its snowy the front spins then 4wd flashes and nothing happens. I have serviced the transfer case and rear end. Im at a loss, really blows the drive in the winter like this

 

[smario259]

What is servicing the rear end? Is it more than a diff fluid change? When the 4wd flashes upon a spin on ice or snow, it is because the ECU issued a command to the rear diff clutch to engage but it sees no reaction from the abs sensors. I do not know if an open circuit in the cable going to the diff clutch (or the clutch solenoid) can be detected by the ECU. My 05 v6 has its drive shaft and rear axles removed, but the diff is still present, doing nothing, connected to its electric clutch cable. What you are describing is what happens when mine slips on ice /snow. The system may be different on an 07.

 

[ProjectSHO89]

The 05 and the 07 have the same rear drivetrain.

If the driveshaft turns normally, the problem is the rear differential or the control module isn't issuing the proper signal to the TCC in the rear differential. Repair consists of replacing the whole differtial if the TCC is indicated as faulty.

If the driveshaft does not turn, the PTU is busted internally.

 

[JohnCT]

Adding to what projectsho said, you need to see if the driveshaft is turning. The AWD clutching is done at the back, but the whole front drive system is mechanical - the driveshaft to the rear must turn by design.

My 05 AWD went out, so I jacked up the front of the vehicle and kept the rear wheels on the ground. I put it in drive and carefully let off the brake, then even added gas. If you try this, let the brake off slowly and see if the car tries to move forward. In my case, the front wheels turned but the driveshaft stayed motionless. This means a mechanical problem either in the transfer case or transmission, both big jobs. No more AWD for my 05.

My symptoms were exactly the same as yours - it rode and drove normally until I hit snow or rain on a hill. The front wheels would spin and then the AWD light would flash. No ABS light on. If your ABS light is on, then investigate a bad tone ring or wheel speed sensor.

If the driveshaft turns, but the rear wheels don't get power, there's a problem with the rear diff not clutching, and this could be electrical/sensor/ABS in nature or a mechanical problem with the rear diff itself.

John

 

[dbass4856]

Adding to what projectsho said, you need to see if the driveshaft is turning. The AWD clutching is done at the back, but the whole front drive system is mechanical - the driveshaft to the rear must turn by design.

My 05 AWD went out, so I jacked up the front of the vehicle and kept the rear wheels on the ground. I put it in drive and carefully let off the brake, then even added gas. If you try this, let the brake off slowly and see if the car tries to move forward. In my case, the front wheels turned but the driveshaft stayed motionless. This means a mechanical problem either in the transfer case or transmission, both big jobs. No more AWD for my 05.

My symptoms were exactly the same as yours - it rode and drove normally until I hit snow or rain on a hill. The front wheels would spin and then the AWD light would flash. No ABS light on. If your ABS light is on, then investigate a bad tone ring or wheel speed sensor.

If the driveshaft turns, but the rear wheels don't get power, there's a problem with the rear diff not clutching, and this could be electrical/sensor/ABS in nature or a mechanical problem with the rear diff itself.

John

I have the same problem except my abs light is on. I checked pads and they are good. Drove on slick roads and rear doesn't engage. Fuel pump was just replaced but it still throws same 2 codes after driving a few miles.

 

[dbass4856]

I have the same problem except my abs light is on. I checked pads and they are good. Drove on slick roads and rear doesn't engage. Fuel pump was just replaced but it still throws same 2 codes after driving a few miles. Just bought it but don't know it's history.

 

[JohnCT]

I have the same problem except my abs light is on. I checked pads and they are good. Drove on slick roads and rear doesn't engage. Fuel pump was just replaced but it still throws same 2 codes after driving a few miles.

If the ABS light is on, you might be only looking at a bad tone ring on one of the axles. If the powertrain computer doesn't get accurate wheel speed info from all four sensors, it can't determine accurate wheel spin or slip. If this happens, the ABS system gets shut off to prevent extended braking times and the AWD is also shut off.

Look at all four tone rings and see if one is broken or even cracked.

John