Electronic 4X4 Questions

Hey ya'll soon going to put my moms 93 Eddie Bauer Aerostar on the road, it has the Electronic 4X4 so I know it's not AWD does it operate like the 4X4auto in my 96 Explorer that it has its own Clutch Coil in the transfercase that engages it into 4X4? Because when I tried it one time bout a month or so ago it didn't seem like it was engaging or does it have a shift motor on the t-case that puts it in 4X4 or is it both? Lol sorry for it being long but would like to make sure it's running right before she goes and drives it on the road luckily its bout the same build of the explorer kinda, thanks for any info you can throw at me. :iceslolan

The transfer case is equipped with a magnetic clutch, similar to an air conditioning compressor clutch, which is located inside the transfer case adjacent to the 2W-4W shift collar. The clutch is used to spin up the front drive system from zero to vehicle speed in milliseconds. This spin-up allows the shift between 2-high and 4-high to be made at vehicle speeds listed in the vehicle owner's guide. The spin up engages the front lock hubs. When the transfer case rear and front output shafts reach synchronous speed, the spring-loaded shift collar mechanically engages the mainshaft hub to the chain drive sprocket and the magnetic clutch is then deactivated. Shifts between 4-high and 4-low can only occur with the transmission safety switches closed. The vehicle's speed must also be within specified limits as determined by the transfer case speed sensor (3 mph or under).

With that said this is a part-time 4WD system that should not be used on hard dry roads. To test the system look for torsional windup, simply put it into 4WD on a dry paved road and make a few sharp turns, if the front wheels start to hop and the steering starts to jerk all is working fine.


Hey ya'll soon going to put my moms 93 Eddie Bauer Aerostar on the road, it has the Electronic 4X4 so I know it's not AWD does it operate like the 4X4auto in my 96 Explorer that it has its own Clutch Coil in the transfercase that engages it into 4X4? Because when I tried it one time bout a month or so ago it didn't seem like it was engaging or does it have a shift motor on the t-case that puts it in 4X4 or is it both? Lol sorry for it being long but would like to make sure it's running right before she goes and drives it on the road luckily its bout the same build of the explorer kinda, thanks for any info you can throw at me. :iceslolan

Ok thank you for the info, nice to know how the thing actually works :)

How do you put the Areostar in four wheel drive if it only engages when a wheel slips? there is no shift.

The way I understand it, you can't manually engage it to 4X4, unless you can mod it like my explorer, you would think ya could, like you could cut the wire that supplies power to the coil in the t-case and connect a 3way toggle switch one with direct power and the other with the automatic power so you could flick the switch one way and have full-time 4X4 and the other flick for just automatic 4X4 or have the toggle switch in middle position for just 2wd. But I don't know much bout the electrical system in the aerostars so don't know if that mod is possible or not.

Good call Thanks Im on it.

You could also put an explorer/ranger t-case on it to have a regular 4wheel system

Hi There
This is as I understand it.
I've had a AWD Aerostar since 1990. I also have all the factory manuals for it including the EAWD

AWD means All Wheel Drive. (Always in use)
In normal condition the transfer case distributes the power 60/40.
60 % to the rear wheels, and 40 % to the front wheels.
When the sensor on the rear axle senses a slipping rear wheel, it closes the clutch in the transfer case. Then the power is now 50/50.
This action is only momentary (not constant) it will cycle on and off as long as the rear wheel sensor tells it.

I hope this helps
Willie

That makes no sense at all, its impractical and has no advantage.


Hi There
This is as I understand it.
I've had a AWD Aerostar since 1990. I also have all the factory manuals for it including the EAWD

AWD means All Wheel Drive. (Always in use)
In normal condition the transfer case distributes the power 60/40.
60 % to the rear wheels, and 40 % to the front wheels.
When the sensor on the rear axle senses a slipping rear wheel, it closes the clutch in the transfer case. Then the power is now 50/50.
This action is only momentary (not constant) it will cycle on and off as long as the rear wheel sensor tells it.

I hope this helps
Willie

That's the way I've heard too that its not completely a 4X4 system its like awd but will do a 50/50 split if a rear wheel slips. Don't make much sense to me why Ford would have done such a thing. Right now the van isn't on the road anyway its having some running problems, and the room under the hood isn't enough for me to mess with it. I don't know how anyone puts up with these vans that does their own motor work.

Hi There
This is as I understand it.
I've had a AWD Aerostar since 1990. I also have all the factory manuals for it including the EAWD

AWD means All Wheel Drive. (Always in use)
In normal condition the transfer case distributes the power 60/40.
60 % to the rear wheels, and 40 % to the front wheels.
When the sensor on the rear axle senses a slipping rear wheel, it closes the clutch in the transfer case. Then the power is now 50/50.
This action is only momentary (not constant) it will cycle on and off as long as the rear wheel sensor tells it.

I hope this helps
Willie

SECTION 07-07F Transfer Case - Electronic Four Wheel Drive - Aerostar
Operation
The transfer case receives engine torque through the transmission. One third of the torque is sent to the front axle. Two thirds of the torque is sent to the rear axle. This torque split favoring the rear axle allows the vehicle to handle in a manner of a rear wheel drive vehicle but with the response of a front wheel drive vehicle. This function is made possible by the use of a planetary gear differential.

The planetary gear differential delivers torque to the front and rear axles while allowing both axles to turn at different speeds. This is especially important when the vehicle is turning because it prevents driveline "wind-up." During difficult driving conditions (wet or slippery roads) the transfer case can send all necessary torque to the front or rear driving axles to maximize vehicle traction.

The control unit senses when a wheel is slipping and activates the electric clutch assembly in the transfer case. The electric clutch consists of an actuator coil, an armature and clutch plates. When the clutch plates are compressed the front and rear wheels rotate at the same speed and the planetary gear set does not opperate. The control unit engages the clutch for approximatley 3.3 seconds and then releases. If wheel slip continues, the clutch will re-engage after approximatley .5 seconds and will continue to cycle as long as slip condition exist. The driver may notice a slight pushing or bumping sensation as vehicle traction increases.

The control unit will not allow the clutch to engage when the service brakes are applied and the vehicle is going 5 mph or faster, or the transmission selector is in PARK or NEUTRAL postions.

Source-
1990 Aerostar Electronic 4-Wheel Drive Transfer Case
Service Literature Update
Ford Parts and Service Division Service Publications
SLU/FPS-12199-90-3, April, 1990
Page07-07F-1
There, and that's a lot of typing...

Wow !! that is useful info thanks. I just had to know because the truck is used to tow a fishing boat to some vary tough places. I think and most every one who sees the set up. That it is the best tow and sleep truck on the market. It pulls like a Clydesdale and gets about 28 mpg. No it doesnt look as good as your 96 looks more like a Winnebago but I had a rear tent made to fit the hatch. and Wow I really like this truck for what it is. Cheep on fuel $360 a year to insure rust free tough and dry. Thanks again

I'm not an aerostar guy and haven't driven one much to know how well they do but they're a Ford so I expect them to drive as well as an explorer in snow.