Explorer AWD T-cases?

[Blown]

I found this:
"1997 Ford Aerostar: A new 5-speed automatic transmission arrived for '97 (the 5r55e), which turned out to be Aerostar's final season. The 5-speed came only with the 4.0-liter engine, which was standard on E-4WD Aerostars. This minivan was discontinued at the end of the year."

This Aerostar t-case is a Dana 28, AWD, uses a clutch and sensors on each drive shaft so when the rear is slipping it applies power to the front. It is AWD without clutch engagement with a 30/70 split. It would take getting the sensors and box that controls it if yo wanted it to be automatic 4wd.

 

[Blown]

I found this:

"Aero's have a weak marginal AWD system that is not designed to run with the transaxle clutch in lockup all the time.
You will know when the clutch kicks in by the computer. The first time it did on me I was pushing snow with the front bumper and slide off the road somewhere I should not have been, Oh S???, sat there for awhile red faced, put it back into drive, eased the gas on, the AWD clutch kicked in, the wife laughed from joy and away we went, right around a big real 4wdr Bronco that was in over his head and not going anywhere.
turned around and got the hell out of snowed in Dodge.

Transfer Case System, E-4WD
The Dana TC28 transfer case (7A195) is mounted on the rear of the transmission (7003) and operates full time. The control module, located under the driver's seat, actuates the transfer case clutch under adverse conditions.
The electronic four-wheel drive vehicle has engine torque available to all the wheels on a full-time basis. This improves vehicle handling and traction during difficult driving conditions.
The control module senses wheel slip and locks up the interaxle differential as necessary via an electromagnetic clutch. This is an automatic function and does not require any driver input.

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 the manner of a rear wheel drive vehicle but with the response of a front wheel drive vehicle. This function is made possible by 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 pressure plates (7563). When the clutch pressure plates are compressed, the front and rear wheels rotate at the same speed and the front planet (7A398) does not operate. The control unit engages the clutch for approximately 3.3 seconds and then releases it. If wheel slip continues, the clutch will re-engage after approximately .5 seconds and will continue to cycle as long as slip conditions 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 both of the following conditions are present: the vehicle is going 8 km/h (5 mph) or faster and the service brakes are applied. Also, the clutch will not engage when the transmission selector is in the park or neutral positions."

 

[Blown]

Then this:

I wouldn't say that the AWD system was weak or marginal. The axles are, for sure, but the AWD system itself was pretty state of the art in 1990.

Given the electronics of the time, it did a pretty good job, and the full time center diff gives the vehicle better dynamic behavior then an on-demand part time 4WD system would have. In truth, there are a number of modern AWD vehicles on the market today that have conceptually very similar AWD systems, improved only by the use of modern electronics and sensors. It was actually somewhat a head its time.

From what I was told by the Aerostar's AWD system chief engineer (who we now work with on new projects at Ford), the clutch was fairly beefy and had good torque capacity. I think the only problems with the AWD system as a whole are the dated electronics...
_______________

I read that you can wire a switch to actuate the clutch, 50/50 split when needed to get 4WD. I see both the ranger and 1997 Aerostar AWD listed in the 5R55E Transmission manual, so the 97 aerostar T-case will bolt-up! I want to get my hands on one of them now to see what driveshaft mods would be needed.

 

[JoshT]

Good find on the Aerostar info. It's normally a fulltime AWD with a 30/70 split, and the electronics lock it to 50/50 when slippage is detected. You could probably even add an override switch to lock it into 50/50 manually when you feel you need 4wd engaged.

For that matter do away with the electronics entirely, let the transfer case run as 30/70 full time, and use a switch to engage 4wd when needed. Not like TOD is really needed, the Explorer V8 AWD is full time 30/70 split with no option to vary it.

I̶ ̶h̶a̶d̶ ̶d̶i̶s̶m̶i̶s̶s̶e̶d̶ ̶t̶h̶e̶ ̶4̶4̶0̶5̶ ̶e̶a̶r̶l̶i̶e̶r̶ ̶t̶h̶i̶n̶k̶i̶n̶g̶ ̶t̶h̶a̶t̶ ̶i̶t̶ ̶w̶a̶s̶ ̶b̶a̶s̶i̶c̶a̶l̶l̶y̶ ̶a̶ ̶2̶w̶d̶ ̶t̶r̶a̶n̶s̶m̶i̶s̶s̶i̶o̶n̶ ̶t̶h̶a̶t̶ ̶e̶n̶g̶a̶g̶e̶d̶ ̶4̶w̶d̶ ̶w̶h̶e̶n̶ ̶s̶l̶i̶p̶ ̶w̶a̶s̶ ̶d̶e̶t̶e̶c̶t̶e̶d̶.̶ ̶N̶o̶w̶ ̶I̶'̶m̶ ̶w̶a̶n̶d̶e̶r̶i̶n̶g̶ ̶i̶f̶ ̶i̶t̶ ̶w̶o̶r̶k̶s̶ ̶s̶a̶m̶e̶ ̶a̶s̶ ̶t̶h̶e̶ ̶t̶h̶e̶ ̶T̶C̶2̶8̶,̶ ̶3̶0̶/̶7̶0̶ ̶f̶u̶l̶l̶ ̶t̶i̶m̶e̶ ̶t̶h̶e̶n̶ ̶i̶n̶c̶r̶e̶a̶s̶e̶s̶ ̶t̶o̶ ̶5̶0̶/̶5̶0̶ ̶w̶h̶e̶n̶ ̶s̶l̶i̶p̶p̶a̶g̶e̶ ̶i̶s̶ ̶d̶e̶t̶e̶c̶t̶e̶d̶.̶ EDIT: Never mind this idea, forgot about the brown wire mod for Explorers with the 4405. It's used to lock the transfer case into 2wd mode (or prevent 4wd operation), so I guess I was right about it being a part time case.

Damned it now I'm really thinking about this again.

 

[Blown]

I am going to get one as soon as I pay off a couple Christmas things. It would be the best of both types of cases. You could lock it with the flip of a switch in low low speed low traction situations.

The parts guys want to know if you have an Aerostar with aluminum drive shaft or steel driveshaft to determine which T-case you need. I need to research that. I'd go out to a pick n pull but it's been damn cold here in Denver. I'll likely pull my own in the spring.

Edit: A case was updated and aluminum driveshaft added to take care of a problem, we want the upgraded T-case that came with an aluminum dirve shaft.

 

[JoshT]

I'd join you in that attempt, but looks like all my big expenses are coming after Christmas. Was planning to pay off my car with income taxes, do some work on the truck, and enjoy the extra cash in my pocket.

Instead my home owner insurance just delivered a list of urgent fix items from a recent "routine" policy inspection. So it looks like I'm getting a new roof and probably going to have to build a garage.

 

[Blown]

I shouldn't have been looking, found a new Dana 28 for Ford Aerostar for $160 shipped on ebay!

I thought I would spend twice that for a used unit. My guess, these are not that much in demand.