Speaking only regards the only defender I have worked on - my own 2.2l TDCi:
- swapping ECUs is a dead easy task. 10min job once you've done it once before. Two small bolts to get the engine top sound deadening cover off. Two small nuts hold the ECU to its mount. 3 cabling plugs to pull.
- absolutely love the ATBs. Wrote up a couple of lengthy reports on them. Later when home will find and post links. Wouldn't say everyone should buy them. They are not a small expense and won't meet every need. But they are exactly what I wanted. In summary:
- they don't ever send all drive to any one wheel so no need to go down the path of replacing every transmission component with HD versions.
- they work for you delivering benefits BOTH on road and offroad
- got rid of a potential weak point (2 pinion diff) and got rid of a source of drive line backlash
Edit: here is the link I mentioned on ATBs. The first post gives a lot of background. On page two I added an update after 7mths and 10,000km living with ATBs
Fitted Ashcroft ATBs front and rear
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