I wheel with a regular group in our club and it's a mixed bag of trucks, GQ's, 80 series, Hilux's & Surfs SAS & IFS, Pajeros SAS & IFS, Suzuki's and bloody Prado's
all of these 4WD's are running 35" & bigger tires with some having big mods done to them, all are twin locked 4by's of either mechanical or ARB in them.
The tracks we play on are hard ones (Abbotts link/creek, Burns, Lady Sutton Manor to name a few) and most of the times we are shown up by the IFS bandits. The wheel lifts make for awesome DVD footage.
The IFS setup seems to cop a bagging by 4WDers in general, but if you modify them to suit the driving style your after (as with any 4WD) then they will serve you well.
As for breakages it's a "much of a muchness" I feel, when I had the IFS in my 4by I ran 1" ball joint spacers with 3"susp lift, 34 JT2s, f & r lockers and only broke 2 inner axles and never a front diff, bent a few idler arms and stuffed tie rods approx every 12mths (not bad really considering the amount of hard driving I did) Now since then I've had a solid front put in, slotted a V8 in, had a little bit more lift done to squeeze a set of 36's under it and I've managed to smash just about everything in the front diff before paying out for toughened CV's (Haultecs) Lonfield axels, treated ring & pinion gears, tuffer uni's etc. AND still those bloody IFS buggers are going where I go (sometimes further
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