Hyundai Motor Group A6LF1

Transmission general data

The automatic transmission A6LF1 is a part of 6-speed transmissions family (A6LF2/3, A6GF1, A6MF1 /2) produced by Hyundai. This transmission is an expensive and comfortable alternative to the 5-speed automatic transmissions A5HF1 (A5GF1). These transmissions had been tested since 2009 on a limited series of Hyundai Avante HD\MD and after 2-3 years of modifications were installed on luxury FWD and AWD cars Hyundai (Sonata, Opirus...) and Kia models with engine capacity from 1.4 up to 3.8 liters.

Technical issues and repair guidelines

Aggressive accelerations and critical overheats may lead to replacement of rings and valve body gaskets. After covering over 150 thousand kilometers replacement of the whole repair kit is considered to be a routine procedure. The aim of this measure intended for protecting solenoids which have to deal with higher loads caused by increasing oil leakages through sealings. The main signs of the problem are the following: wear-out of the torque converter lock-up, rapidly contaminating transmission fluid, and issues with gear shifting. The valve body disassembly usually indicates critical contamination and sticking of valves.

Insufficient oil pressure (caused by problems with the valve body or leaks of ATF through rings, jointing edges and as a result wear-out of solenoid valves) in most cases leads to burning of friction elements with Overdrive and Underdrive discs, but often drivers neglect this problem, resulting in replacement of all friction clutches and steel discs which operated in burnt ATF. Contaminated ATF from this package damages corresponding valves and solenoids of the valve body.

The vulnerability of the A6MF1/2 transmissions resides in burning of clutches 3-5\R and 2-6. For replacement of these burning packages, Hyundai released the kit of "Power Pack" friction elements with steel and bearing discs.The Overdrive is also frequently replaced by repair specialists. The problem is explained by overloads caused by contaminated fluid, resulting in wear-out of teflon rings on the rear cover and pressure losses in packages.A typical problem for Hyundai differentials is related to damage of splineways of the differential body under the condition of longtime and frequent wheels slippages. During the first years of testing, the main problem lies in the valve body and solenoids (problem identical to ZF transmission ZF6HP from which the valve body operation principle was adopted).

The most failure-prone solenoids are the following:

1. EPC solenoid

2. TCC solenoid.

3. Shifting solenoids

Another frequent problem for this transmission (as well as for other 6-speed automatic transmissions) is related to the torque converter clutch wear-out. The more often drivers use aggressive accelerations, the closer this transmission to the repair shop.

The valve body may be considered a soft spot in the electrical part of the A6MF2 \LF2 transmission. As in all 6-speed automatic transmissions, the A6LF1 valve body is very sensitive to overheating and contaminated ATF, which first of all may be provoked by wear-out of the torque converter friction and clutch packages and in chain order lead to (pressure shortage from solenoids and the valve body) more rapid wear-out of frictions in packages of clutch and braking. Problems at the early stage are usually solved by repair and cleaning of the valve body and solenoids, opening of the torque converter for replacement of spare parts. In more complex repair cases, transmission specialists have to repalce solenoids.