A while ago I swapped the whole rear axle in my 4.6 with one off a breaker. Although the nose bearing wasn't actually allowing the input shaft to flap about like the one I took off, it did have a bit of play and the diff emitted quite a lot glitter when I dropped the oil out.

A few thousand miles later and while it hasn't really got any louder, it also hasn't got any quieter, so I'm thinking about just changing the diff out. However, it looks like 2-pin rear diffs are far cheaper than 4-pin ones, which were fitted to the 4.6es with traction control.

Now opinion seems to vary on how much of a difference this makes. Ashcrofts want to sell you a 4-pin and seem very keen that people don't run 2-pin diffs. On other forums opinion seems split between "yes a 2-pin will break as soon as you pull away gently on dry tarmac" to "never seen one break yet and I tow artics through wet sand for fun". The "it'll break instantly" posts do seem correlated with people who post pics of their Landies with massive tyres and mud up to the headlights.

So I turn it over to the sensible crowd. Does it actually make that much of a difference?

I don't think so. For the first 8 years of it's life mine was used by GMP for dragging dead artics off the M6 and only has a 2 pin on both ends.....

I guess one way to look at it, is that Landrover themselves went to the effort of engineering a different, stronger diff for the 4.6 models.

Big OEMs absolutely do not waste money on things like that for no reason.

They also added a 4 pin front diff when they switched to 4 wheel traction control. Again, this wasnt done for fun.

Evidently some engineering calculations showed the stock 2 pin diff was marginal on the 4.6, but okay on the diesel and 4.0. And similarly, adding front traction control caused them to switch out the front diff as well. This is likely becuase the activation of TC can cause additional loads thru the diff centre when the system grabs a spinning wheel and forces the diff to divert power suddenly.

It may well be ofcourse that these issues only showed up in certain offroad conditions using lots of throttle in low range etc, and as a result a road driven p38 will be totally fine with a 2 pin. Which probably explains why as you've noted, heavy offroad users find them failing and many folks will say its fine.

At least, when all wheels have grip, the power is distributed evenly, which should be easier on the diffs, even if you are towing or flooring the pedal with the humongous power of the 4.6....

th.

Well yes, that's what I wondered about, would those devastating 20bhp extra that the 4.6 brings make that much of a difference?

And so I bought a 2-pin, and if it breaks hopefully it won't do that before I learn how to rebuild the 4-pin.