Long title, I apologize. I'm chasing out an A4WD problem on my 2010 with an uncooperative dealer. The truck cannot be driven in A4WD because it acts like it is in 4WD (binding in corners, drive line whine). They can replicate the binding, but only on sharp turns, and they don't get any codes so their solution is just don't turn the wheel that sharply. Bunch of nitwits. I've got 350k miles in Expeditions and have never had them out of A4WD, and not ever had this issue. They refuse to address the issue or believe it is in 4WD. I suspect there is a speed sensor acting up. My question is will a scan tool with live data show the A4WD has engaged 4WD?

 

Bump bump bump

 

The answer to your question is yes however if you are asking the question it means the dealer probably does know more than you. I know this sounds stupid but since you are asking this question I have to ask you are sure that the tires are all inflated to the same pressure AND are stock size AND are the same brand and model even from the same lot number?


You always have some bind in AWD and you will gain driveline noise as the vehicle ages.

 

it definitely should be able to be seen on a scan tool. if it's controlled electronically by a module, it should be able to be read on a scan tool, especially ford's oem tool. make sure not to overlook your other drivetrain components like driveshafts or cv axles. a bad u-joint can whine and a bad cv axle can make noise when turning sharp. also check your iwe's, if you are losing vacuum to them, your front hubs will stay engaged.

 

I appreciate the answer, somewhat snide, but an answer none the less. In all my Expedition seat time with this A4WD system across 4 vehicles I have never had binding in any of them except this one. As a matter of fact all those miles have been driven in A4WD without any sign of lock up. The tire question isn't stupid, but it also isn't the issue here, they are brand new and identical (the smarter than me dealer checked that also). They confirm binding but other than looking for static codes have done nothing other than keep the car for 10 days over 3 visits, and suggest not turning the wheel sharply.

 

Appreciate the suggestions, when I go in again I will have them double check. They can do that right after they get live data. Thanks.

 

You should check the front hubs that engage the 4wd. If they don't function properly, locked because rust, dried-up grease, loss of vacuum than the car will stay 4wd all the time. Unfortunately the only way to check it is to take it apart by removing the front wheel CV joint from the wheel and check the movement in the hub.