Years ago I started get the rear end clunk and AWD 4 code, we finally found out that you could unplug the controller under the seat and it would drive but with out full 4WD. Then about a year ago the trans died did a swap with a 1993 Aerostar we re-sealed it and then we got a AWD 9 code. I worked on it with my mechanic got it to go away with new tiers tires but it still did the clunk when truning sharply but didn't give a code. Then today I am geting a AWD 3 code whenever I put it into drive, theres no clunk but it flashs as you dive. So should I pull out my hair or is there a way to fix this.

Its a 1992 Aerostar AWD with about 185K on it.

Thanks,
-Scott

 

front driveline speed sensor on the top of the transfer case is defective or it's wiring/plug is damaged. located on top of case over front driveline.

from Ford Svc CD

³ 3 ³ Front output speed sensor connector or ³ Go to Step E1. ³
³ ³ internal circuitry of sensor has ³ ³
³ ³ discontinuity.


sources of transfer case sensors has dried up. Ford quit stocking them several years ago. Junkyard dog is one solution if it's the sensor or cable end.

love my AWD Aero. only minor problems in 14 years. reliable and works with the good weight balance of the Aero. more stable and certain of making it thru icy highways than my Dodge 2500 diesel 4wdr

 

Thanks for your reply, don't the front sensor get the speed?

 

three pages on the Aero Dana 28 TC

Up To Standards 6-99

check out this supplier, they may? have the sensors
Dana 28 Transfer Case Aerostar Van's Parts Illustration & parts list! - Drivetrain.com

search the Aero forum for AWD transfer case sensors. there are several troubleshooting threads that give ohm meter readings go/no go for the sensors and add. info on troubleshooting the wiring

 

Thanks I'll get to work!

 

AWD is great. Mine is acting up too, but even disabled it beats out 2WD. I plan on swapping on a case to resolve my issue, since mine is a code 2, and I figure swapping out a complete case will be easier than replacing the clutch. Overall, the AWD works great, and its only because these vehicles are getting so old that there are any problems.

 

At the risk of sounding stupid here, but are you saying that with the 4x4 disabled the front still spins? Thanks.

 

Welcome to FTE!

Yes it does. What they are talking about is disabiling the computer that kicks the system from 4x4 Hi to 4x4 Low.

 

When you run an open differential, bot wheels still spin. The AWD in the Aerostars is nothing like the 4WD in a truck. You always get torque to all the wheels. When slippage is detected, the clutch inside can lockup, giving you a 1:1 ratio front to rear, otherwise you get an approximate 30:70 split.

On an Aerostar there is no 4 Low.

 

I was attempting to give jubangy an explination In laymens terms Bear, when the computer locks up the clutch during slippage to give you 50/50ish power, an analagy that I thought fitting in using is the similiarity to an old style transfer case going from 4 Hi to 4 Low for better traction/pulling power.

The AWD system in the Aero is 100% all the time.