08 f150 limited with 34,000 miles
11-07-2010, 04:51 PM
#1
08 F150 LIMITED
Thread Starter
08 f150 limited with 34,000 miles
This truck has All Wheel Drive and 4 Wheel Hi, it's got a 5.4 motor, 4 speed auto trans.......I think I have a problem with the AWD on it because if I get in mud or on a slippery surface and from a stand still
give it gas there a gear jult at one of the wheels, then if I put in reverse and try to back up it jults one of the wheels again and makes a clunk sound only at the begining of the pull and then goes on just fine....does anybody know something about this? I don't think Ford designed it to do this, I'm thinking theres some play in the axles at the rear ends...help me if you can and thanks!!
give it gas there a gear jult at one of the wheels, then if I put in reverse and try to back up it jults one of the wheels again and makes a clunk sound only at the begining of the pull and then goes on just fine....does anybody know something about this? I don't think Ford designed it to do this, I'm thinking theres some play in the axles at the rear ends...help me if you can and thanks!!
11-07-2010, 10:31 PM
#2
Reading this thread on the AWD vs 4WD it seems that there isn't a clear cut description of how the AWD engages. Though I'd assume its just like my wifes AWD Explorer and my old Cherokee with AWD. The truck is not actually AWD until it detects slip, then it engages the front wheels.
I'm not sure if the transfer case is always engaged, or if the front axles are always engaged (opposite of how the F150 front axles operate on other models) in the AWD versions. Therefore, its hard to say where the clunking could be coming from.
However, what you describe actually sounds normal. In the Explorer owners manual it says that when the system engages a crunching or grinding noise is normal. It's the mechanical elements of the system catching up with eachother.
If the front axles are live on the AWD 150's then the transfer case is more than likely what engages provably via a viscous clutch (same way my Explorer does). If the transfer case is always engaged then it probably engages the front hubs with the IWE (like how you engage typical 4x4, only its automatic) when it detects slip. You could be hearing the front hubs locking up. However, shift on the fly doesn't have this problem in the other models so problem/answer isn't really clear cut here without solid evidence of how exactly the system operates on the front hubs/axles and the transfer case. Hopefully a member here knows more.
I'm not sure if the transfer case is always engaged, or if the front axles are always engaged (opposite of how the F150 front axles operate on other models) in the AWD versions. Therefore, its hard to say where the clunking could be coming from.
However, what you describe actually sounds normal. In the Explorer owners manual it says that when the system engages a crunching or grinding noise is normal. It's the mechanical elements of the system catching up with eachother.
If the front axles are live on the AWD 150's then the transfer case is more than likely what engages provably via a viscous clutch (same way my Explorer does). If the transfer case is always engaged then it probably engages the front hubs with the IWE (like how you engage typical 4x4, only its automatic) when it detects slip. You could be hearing the front hubs locking up. However, shift on the fly doesn't have this problem in the other models so problem/answer isn't really clear cut here without solid evidence of how exactly the system operates on the front hubs/axles and the transfer case. Hopefully a member here knows more.