Hi guys,
Can anyone tell me if AU hydraulic engine mounts be used to replace EL hydraulic mounts.
If so are they more reliable and do they work better.
Many thanks

You can use them sqaure ones and the round ones, they are interchangeable. A lot of blokes with taxis used to change them over.

When I fitted the AU series II donk to my NF fairlane, I ruptured one of my EF engine mounts. I figured I would just install the AU series II mounts but had clearance issues. The stud that protrudes from the bottom of the hydro-elastic mount is thicker and so the nut larger that sit over the steel base bracket. The nut is too big to fit thru the chassis hole (not the horizontal bolt). In my case I used a step drill to enlarge the hole and all was sweet.

I believe this problem only relates to AU series II and III engine mounts being fitted to EF/EL vehicles.