Tales of a 3.9 litre Tdi Bushie Ute

Bushie Transfer

Bushie Ute has a two speed Atlas II transfer case with ratios of 1.0:1 in high range and 5.0:1 in low range.

Atlas II transfer cases can provide drive to:

  • the rear wheels only, in either high or low range (2WD), for normal driving on high traction surfaces
  • the front wheels only, in low range (2WD), for making tight turns on loose surfaces
  • both front and rear wheels, in either high or low range (4WD), for low traction surfaces

The Atlas has the unique feature of 2WD low with the rear axle or the front axle. At any time while driving in low ratio, you can disengage either the front or rear by shifting the respective handle into neutral.

PDF Documents for Atlas Transfer Case
(click on the link text to open or save the document)
Atlas User Manual
Atlas Service Manual

 

Atlas Power Flow 2WD & Neutral

Atlas Power Flow 4WD

TWIN STICK SHIFT POSITIONS
Neutral:
Both the “rear” and “front” knobs in the “N” position.
2WD High:
The “rear” knob in “H” position and the “front” knob in “N” position.
4WD High:
The “rear” knob in “H” position and the “front” knob in “H” position.
4WD Low:
The “rear” knob in “L” position and the “front” knob in “L” position.
2WD Low:
(Rear Drive ONLY) The “rear” knob in “L” position and the “front” knob in “N” position.
*2WD Low: (Front Drive ONLY) The “rear” knob in “N” position and the “front” knob in “L” position.

*Special Note: With the front in 2WD low, the torque is distributed 100% to the front axle. Combined with the low gearing in the transfer case, these factors can cause undue strain on your front axles. This should only be used for quick tight turns in loose soil conditions. The only shift position that is not available is Front 2WD high.

SHIFTING AN ATLAS TRANSFER CASE:

Shifting from High range to Low range:

  1. Verify that the “FRONT” lever is in NEUTRAL.
  2. Bring the vehicle to a speed of about 5-8 km/h and depress the clutch.
  3. Shift the “REAR” lever into NEUTRAL. As the vehicle continues to roll forward, smoothly apply pressure to the “REAR” lever toward the LOW position and continue to apply pressure until the Atlas drops into REAR LOW. Depending on which low range ratio is installed in your Atlas, the shift will usually complete just before the vehicle rolls to a stop.
  4. Engage the clutch and resume driving. Do not hold pressure on either shift lever as the clutch is engaged.
  5. If 4WD LOW is desired, then shift the “FRONT” lever into the LOW position while the vehicle is moving straight forward.

Shifting from Low range to High range:

  1. Bring the vehicle up to a speed of 8-32 km/h and shift the transmission into neutral.
  2. Shift both transfer case shift levers into neutral.
  3. Apply pressure to the “REAR” lever toward the HIGH position until the Atlas completes the shift into REAR HIGH (2wd high).
  4. Put the transmission back into gear and resume driving.
  5. If 4WD HIGH is desired then shift the “FRONT” lever into the HIGH position.

Once the above process is learned, it will take you about 3 seconds to complete the shifting sequence.

What to do if the moving vehicle shift was not successful (shifting while stationary):

Manual Transmission: Put the transmission into gear (with vehicle still stationary) and feather the clutch while re-attempting the desired shift by holding steady pressure on the shift lever. Repeat as needed.

Automatic Transmission: Shift the transmission from drive to reverse while maintaining pressure on the desired transfer case shift lever. DO NOT SHIFT THE TRANSMISSION INTO PARK. If unsuccessful, turn off the engine with the transmission still in neutral. Now shift the transfer case into gear and re-start the engine.

General notes on Shifting:

1. The Atlas Transfer Case is a Synchronised gear box. This means that in order for the case to shift easily and smoothly the vehicle must be moving in a forward direction. This will allow the synchronisers to function properly.

Note that when the transfer case is shifted when not in motion, the teeth may or may not be aligned. If the teeth are aligned, then the unit will slip into gear easily. If the unit does not slip into gear easily, then no amount of pulling on the lever will cause the unit to shift, under these circumstances. Once the transfer case is allowed to rotate slightly, or the binding is relieved it should slip right into gear.

2. The Atlas transfer case will not allow the unit to be shifted into front wheel drive high range. This dictates the sequence of shifting the front and rear axles in and out of high range. One way of thinking about this can be that Rear-High is the path to/from low range. When shifting into high range, the rear axle must be shifted first and when shifting out of high range the front axle must be first.

3. The Atlas is classified as a Part-Time Transfer case. As with all part-time transfer cases, 4wd should be used in low traction conditions only. Anytime the unit is in 4wd low or 4wd high, the rear output and the front output are locked to each other and can only spin at the exact same speed. This characteristic is essential for extreme off road usage, but becomes a hindrance on dry pavement.

When a vehicle turns a corner, the front driveshaft spins at a different speed than the rear driveshaft. This creates a binding in the drive train if the tyres cannot slip to relieve this torque. How does this relate to shifting an Atlas?

When being operated in high traction conditions, the Atlas will not shift to its potential, especially when shifting out of 4wd. If the transfer case becomes stuck in 4wd, try driving at least half of the vehicle onto a surface that will allow the tires to slip before re-attempting to shift out of 4wd. Deactivating locking differentials (if applicable) will also help in this situation.