The big slow down...
As this is the first auto 4wd I have ever own the High Country trip was a steep learning curve. The auto excells in the sand, mud, rocks though hill decents are an isssue. I got caught out a few times on long steep decents with the Tri running away due to the lack of engine breaking.
The MN also has the habit of automatically changing up a gear mid decent once the revs reach around 3000 RPM. These two traits had me white nuckled on more than one occasion. I researched the issue and found that the torque converter is responsible for the over run issue and the computer controling the shift points the other.
I learnt about a 'lock up' kit that electronically locks the torque converter allowing a solid link between the motor and transmission. After following a few threads and searching through the net I came across the Wholesale Automatics run on the reduction gears and trans uprades.
There was a run of 20 sets of 3.15 ratio gears. 10 sets to suit manual and the other 10 to suit autos. These were made by Marks Adapters.
I booked in to have them fitted as well as the lock up kit, Nomad valve body, VDO temp gauge etc.
In comparison the standard gearset is a 1.9 ratio. These are a 3.15 ratio.
Tested at 3000 RPM standard gear ratio.
1st gear = 15 kmp/h
2nd gear = 29 kmp/h
3rd gear = 41 kmp/h
4th gear = 58 kmp/h
The MN won't let you select overdrive 5th gear while in Lloc.
3000 RPM reduction ratio.
1st gear = 5kmp/h
2nd gear = 17 kmp/h
3rd gear = 25 kmp/h
4th gear = 36 kmp/h
We found the steepest hill at Wombat and crawled it down with the lock up switched on in 1st Lloc. It just tickled along full control. I was amazed at the traction !!! On the climb there was no wheel spin so the ASC / TC wasn't cutting in at all. It really has transformed the vehicle.