Thread: Blew my Diff .... :(

The diff used in the Salisbury is way over strong for a Land Rover intended for the use that most here put them to.

There is no getting away from the facts about Salisbury downsides, e.g.

• heavy
• diff doesn't "drop-out" for major diff maintenance
• large, which reduces ground clearance
• too light wall thickness of axle tubes in the standard 110 version, if the vehicle will be driven over many km's of rough roads while overloaded. Note this is unlikely for Salisbury's used 130's as they have thicker axle tubes. The problem with the wall thickness is not the strength, they are comparable to rover axle tubes, but the stress raiser created by the sudden change in stiffness at the transition from the rigid housing to the more flexible axle tube, which can cause a fatigue failure.

The strength limit of a Salisbury rear axle assembly (leaving aside 101's for this post) is the 24 spline half shafts. If more strength is required 35 spline half shafts are readily available and a relatively easy up-grade, which many have done. The diff itself can have 40 spline half shafts, but then there are problems with the spindles and hubs, for no good reason (35 spline is overkill for most here).


For anyone to suggest that a rover diff has remotely similar strength to a Salisbury diff is ludicrous.


IMO, a suitable match for a Land Rover is somewhere in the middle ground between the rover diff and Salisbury diff.


The P38 diff should have been that, but someone stuffed up the design.


What Ashcroft have done to remedy that, will suit many people. IMHO, given 24 spline half shafts being the weak link, it is not unreasonable to suggest/argue that a P38 style axle assembly upgraded with the Ashcroft diff, will match the Salisbury axle assembly strength.



There are other diffs and axle assemblies out there in that middle ground. Ford 9" has been mentioned, but the list is long, given so many 4x4 wagons in the market place with stronger axle assemblies than Land Rover's.

Originally Posted by rangieman

Here is a forum members broken sals like i said a show stopper = flatbed

And the only way Rover could make the Rover housing stronger than the HD Sals was with extensive gusseting and bracing like an off road race rear end.

Originally Posted by rick130

And the only way Rover could make the Rover housing stronger than the HD Sals was with extensive gusseting and bracing like an off road race rear end.

Exactly.

This pic shows the strengthening of the Wolf rear axle housing.

Hi all, my ex-Telstra 130 extra cab's rear axle looks very like that in Bush65's photo. Does anyone know if they are internally improved, i.e. extra pinions etc? Cheers, 130man.

Originally Posted by Bush65

...


What Ashcroft have done to remedy that, will suit many people. IMHO, given 24 spline half shafts being the weak link, it is not unreasonable to suggest/argue that a P38 style axle assembly upgraded with the Ashcroft diff, will match the Salisbury axle assembly strength.

...

That could be simplified to: Both the salisbury and the Ashcroft hypoid p38 are stonger than the 24-spline half shafts.

Hi All,
I have read all this with great interest (and amusement at times). What dif does my 02 TD5 have? P38 or LR?? Or are they interchangable anyway?

Can l fit a diff from a 2010 Defender?

Mike

Originally Posted by mike_beecham

Hi All,
I have read all this with great interest (and amusement at times). What dif does my 02 TD5 have? P38 or LR?? Or are they interchangable anyway?

Can l fit a diff from a 2010 Defender?

Mike

Depends what type of Defender you have.

If it is a 90, you have rover diffs front and back.

If it is a 110 or 130, you have rover in the front, and either Salisbury or P38 style in the rear. IIRC 02 was the when the change over occurred. If it is a 130 and Salisbury it will be the heavy duty version.

But since you had a bearing failure then it is a odds on that you have the P38 style rear diff.

Edit, you can't easily fit the rover diff into the P38 axle housing, or vice versa. The Ashcroft upgrade for the P38 style, has a special diff housing made to fit the axle housing.

Edit 2, yes you can fit a diff from a 2010 Defender, as long as you have the right one. But remember the 2010 Defenders used the same weak P38 style diff in the 110 and 130 models.

It will not be an upgrade, so why not repair you diff with the failed bearing?

Hi,

I have a 110 Wagon. My mechanic is fairly sure it is a bearing - but hasnt pulled diff apart.

So P38/Rover are interchangeable..?
I have sourced a diff from a 2010 Defender, 3.5 ratio (l assume that is standard). It is an LSD also - would that be right??

Thanks again,
Mike