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shogun
08-25-2009, 07:41 PM
I can agree from own experience what is said here for the Landrover, which is also using ZF transmissions:

http://www.europeantransmissions.com/Bulletin/jagtechlib.htm
Ashcroft mentions for the Landrover 4HP22/24:
installation_instructions Check List for fitting ZF Autobox

Please note that a good 50% of our "warranty returns" are due to two basic installation errors.

1)debris and contamination in the oil cooler and oil cooler lines, even if you have flushed them out this is no guarantee they are clean, if the old box has suffered a bad failure you would be wise to replace these.

2)broken oil pump, by not fitting the torque converter correctly, read below.

Assembly

Check engine to bellhousing and Autobox to transfer case dowels are all fitted.

One of the most common causes of failure is the torque converter not being located correctly onto the pump before fitting causing the pump to be broken on start up. To avoid this we would suggest that you stand the autobox upright and lower the torque converter into the bellhousing and once home to do a dimensional check to confirm this using the list below showing the autobox code and the height you are looking for measured from the bellhousing face to the torque converter feet or flange that the flexplate is bolted to. Once the torque converter is inserted and checked make sure it does not fall forward when offering the autobox up to the engine.
With the autobox fitted to the engine, check that the converter will rotate freely and has a small amount (about 2mm) of end float. Bolt the converter to the flex plate using loctite or similar. Ensure the breather vents well away from the exhaust.

Oil Fill

Always use a good quality oil, preferably a Dextron III or similar. Put the transfer case in neutral and fill. Start the engine, the oil level will drop immediately, top back up straight away. Move the shifter lever up and down through the gears slowly whilst checking the oil level and topping up as required. Once the level has stabilised, put the transfer case in gear and the unit should now be picking up drive, this is indicated by the engine revs dropping when put in Drive.

Set up

If the vehicle is a Disco I or Range Rover Classic under no circumstances drive with the kickdown cable disconnected, as this will cause premature autobox failure.

Ensure that the shift assembly is set correctly and full travel of the shifter and engagement of all gears is positive, partial shift will cause premature autobox failure.

If the vehicle is a Disco I or Range Rover Classic you may want to adjust the kickdown cable if you want to fine tune the shift pattern, the looser the cable the softer and earlier the shifts, the tighter the cable, the harder and later the shifts.

Torque Converter Depth Table

The box code is the last 3 digits of the second number down on the name plate on the left hand side of the autobox.

Box Code.....................Depth in mm

061.................................. 22

064....................................22

065....................................27

332....................................51

593....................................51

699....................................51

727....................................27

728....................................83

740....................................51

741....................................51

742....................................51

744....................................18

748....................................18

747....................................27

757....................................27

759....................................27

763....................................83

764....................................27

765....................................27

766....................................96

767....................................27

768....................................83

769....................................83



Automatic Transmissions

OIL TEMPERATURE MEASURED AT CONVERTER OUTLET TO COOLER:

300° F=
The maximum allowable temperature. This is the recommended place to install a temperature gauge or sensor. Do not allow the converter outlet temperature to exceed 300° F. The temperature at this location will vary significantly because of load, hill climbing, etceteras. If the temperature reaches 300° F, reduce throttle. To lower transmission temperature with transmission in neutral, run the engine at 1,200 RPM for at least 2 - 3 minutes while keeping a close check for signs of engine overheating. A transmission in a heavy throttle, stall condition (a typical situation is rocking a vehicle stuck in mud, sand, or snow), may increase temperature at a rate of 1° degree per second of stall.


OIL TEMPERATURE MEASURED AT OIL PAN OR SUMP:

150° F=
The minimum operating temperature. Note: It is possible in low ambient temperatures to overcool the transmission with auxiliary oil to air coolers. Oil to water coolers in standard factory radiators will normally not overcool a transmission.


175-200° F=
Normal pan oil temperature operating range.


275° F=
Maximum allowable oil pan temperature for short durations during long hill climbs.


300° F=
Damage occurs to internal transmission parts, including warpage of metal parts, degradation of clutches, and melting of seals. Transmission oil oxidizes, (forming varnish-like substances causing further clutch slippage and compounding heat build up) and transmission oil life is extremely short.



AUTOMATIC TRANSMISSION FLUID LIFE / TEMPERATURE RELATIONSHIP:

Automatic transmission oil can provide up to 100,000 miles of service before oxidation requires replacement, at an operating temperature of 175° F. Above this temperature, the oil oxidation rate doubles with each 20° degrees F increase in oil temperature. See chart.


Note: Transmission oil and filter should always be changed more frequently when driving with heavy loads (RVs), typically at least every 25,000 mile intervals, since converter outlet temperatures then normally far exceed the ideal 175° F.
http://www.digi-panel.com/digidevicesweb/trannyoil.htm

FAQ

http://www.ashcroft-transmissions.co.uk/faq_part_18.html

BigKriss
08-26-2009, 12:11 AM
good information there. thanks!

ArnZ!
09-01-2009, 08:26 PM
Thanks Shogun. Thats some really good info.