JF404E Friction Transmission parts, repair guidelines, problems, manuals

Transmission general data

Number of gears Transmission Type Drive Torque (Nm) ATF (full capacity) L ATF (change) L ATF type
4 AT FWD 150 7,5 4 Matic Fluid D
Part type (1) Expand

Technical issues and repair guidelines

The valve body has two modifications. The first one has 6 solenoids and higher demand on the market. Solenoids are simple “on-off” electrovalves with a ball, they operate properly during the whole service life of the transmission, even if channels are worn-out by contaminated ATF. There is also a rare modification with the angled filter and 5 solenoids (the second type of the valve body).


Vulnerabilities and repair procedures

Soft spots of old JF404E transmissions are similar to vulnerabilities of JF405E units. But the main reasons for overhauls are related to overall contamination and aging of the transmission, the torque converter wear-out, accumulation of friction dust in the valve body, wear-out of friction elements. If a driver notices problems with the gearbox at the proper time, then the repair procedure involves the valve body cleaning, solenoids washing, torque converter repair. Usually implementation of these procedures adds several years to the service life of the transmission.

When dirty valves of the valve body operate for a long period of time, then wear-out of housing channels of the valve body leads to harmful ATF overflows and necessity to change the whole valve body or more often change of the whole transmission unit. Rare overhauls lie in the gearbox reassembly and replacement of the overhaul kit – repair kit of spare parts, consisting of teflon rings, gaskets, and seals. This transmission is very reliable, not complex in the repair. When monitoring fluid cleanness, preventing a smell of burning, then the transmission will operate for many years without serious problems.