aerostar tcase

what exactly is the tcase in a 4wd aerostar? is it just a ranger case without 4 low and 2 high? we just bought a whole aerostar at work for 100 and i'm gonna take the trans and case.

The Transfer case in an AWD aerostar bears almost no relationship to any Ranger Transfer case.

First off it is a Dana TC28.

No it doesn't have a low range or a 2wd mode, it is a full time Four wheel Drive
transfer case.

It has a planetary center differential which is regulated with an electro mechanical
lockup clutch that is controlled by a stand alone module (a little grey box mounted
under the drivers seat)

If you want me to go into details about what inputs it needs to function correctly and what the engagement paramaters are ask me when I'm not feeling like crap

AD

please go into details allen im trying to find an awd tcase for a progect but they all seem to not be what i want. and any info on awd tcases is nonexistant except its awd.

Ok, the AWD aerostar case because of the nature of it's planetary center diff
splits torque 70% rear 30% front when "open", and of cource 50/50 when locked.

There are two seperate speed sensors on the T-case that monitor
front and rear output speeds.

the module compairs those output speeds and if all other paramaters
are within the preprogrammed "window" the module applies power to
the lockup clutch for 3 seconds, after three seconds it releases
the clutch and "looks" for further slippage (as indicated by different
sensor readings) and if it detects slippage it will re engage the clutch.

The paramaters are (variable depending on specific calibrations)
1)Transmission (automatic) in drive (system disabled in Park and neutral)
2)VSS indicating a speed >5-8mph and <50-55mph)
3)Differential speed (between front and rear output) of >5mph
4) BOO (Brake On Off) signal OFF (applying the brakes releases the clutch)
the control unit must also be connected to a dash indicator lamp
so that it is able to flash out error codes (all single digit codes it
simply flashes an appropriate number of times)
4) and of course power and ground.

The Dana TC28 uses the same slip yoke as an A4LD 2wd transmission
And a front slip yoke output that is similar to that used on a BW 13-50
(I have never checked for compatibility)

depending on what vehicle you are planning on installing it in you might wish
to seek a specific year of AWD T-case as the early ones had provisions for
a mechanical speedometer drive and VSS. later ones (93?-up) used the RABS
sensor signal for VSS input.

This can be played to your advantage in other applications like the unit
can be "fooled" to thinking your road speed is either higher tor lower
than actual speed by.

Like if you install it in a later vehicle that has a RABS driven speedometer
by intentionally using a VSS capable T-case, you can put any "speedometer"
drive gear you like, more teeth would produce engagement at lower speeds
fewer teeth would give you AWD lockup at higher speeds.

but remember that as speeds exceed 55-60mph it's possible to generate that much wheel speed by simply going around a banked turn (like a fast highway onramp)

The last significant advantage of a DANA TC28 is that it bolts to any 4x4 Ranger based vehicle transmission, with one notable exception.

That is the automatic transmission used in the 5.0Exploere AWD models.
Those use a Borg Warner 44-04 t-case and those use the six bolt mounting
flange and input spline of an F-series 4x4.

The 44-04 is a direct drive t-case to the rear axle and there is a multi-disc
thermo-viscous clutch in the power path to the front axle.
the primary purpose of that clutch is to allow sufficient slippage
to prevent driveshaft-windup at highway speeds.

AD

wow awesome write up!