KM175

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A KM175 transaxle from the front
A KM175 transaxle from the rear, shows differential housing and speedometer gear

The KM175 (also known as the F4A22) is a 4 speed electronic automatic transaxle which was fitted to TM and carby TN models.

Two versions of the KM175 were used in Magnas - the KM175-1 in TM and TN sedans (sometimes referred to as KM175) and the KM175-2 in TN wagons. The only difference is the gear ratios.

The torque converter includes a damper clutch which causes the converter to lock at low vehicle speeds. The operation of the clutch is controlled by the Transaxle Control Unit.

Gear selection is electronic and is controlled by solenoids which are activated by the Transaxle Control Unit. The TCU uses information from sensors which provide information on vehicle speed, throttle position, engine coolant temperature, gear lever position, engine speed, overdrive switch and kickdown drum speed.

Technical data

Lubricant Mitsubishi ELC-4 ATF, Castrol TQM-SP, Valvoline Type M-II Special
Capacity 5.8 Litres
Torque Convertor Stall Speed 2200 - 2600 rpm
GEAR RATIOS KM175-1
Final Drive 3.665
1st 2.846
2nd 1.581
3rd 1.000
4th 0.685
Reverse 2.176
GEAR RATIOS KM175-2
Final Drive 3.986
1st 2.551
2nd 1.488
3rd 1.000
4th 0.685
Reverse 2.176

Problems

The KM175 was not suited to the amount of torque generated by the Astron II in the TM and TN Magna. The transaxle wasn't used in the fuel-injected TN and was completely replaced in the TP due to it having a flaring problem with the upshift between third and fourth gear which eventually led to the clutch used for fourth to burn out.