An Archive for Fanatics of Land Rovers
Land Rovers including early series vehicles, Defenders, Range Rovers and Discoverys were produced with a variety of axel differentials. There were 3 basic types of diffs used on Land Rovers, the RR 4.6HSE is not included in this description as it had a lot of unique components.
The 3 types of axel differentials used are the standard Rover diff, Salisbury diff and the ENV diff. Each of them was used on different model Land Rovers for different purposes and they are easily identified by looking at the outer differential casing shape. the explanations below discuss the models of Land Rovers that used these diffs, what ratios they had and how to spot the difference
Front and rear on: All Series 1's, all Series 2's, all Series 3 88", all 90's, all Range Rovers, Discovery 1 & 2 and Discovery 3 rear. It is also fitted to the front axle of all Series 3 109", Series 3s 109, 110s, 130s
The rover diff is the very first ever used, in the first Series ones in 1948.It can be recognised as the smallest of the Land Rover diffs, it is completely removable as a unit from the axle housing. The housing has a downwards bulge in it to make space for the crown heel inside.
All the casings are mechanically interchangeable but not recommended. The insides are different between 4 main era's.
Start (1948) to before first Range Rover (1970) : 2 pinion gears 10 spline and 4.71 ratio
First Range Rover to First 3.9EFi Range Rover (1987?) : 2 pinion gears 10 spline and 3.54 Ratio
First EFI Range Rover to Disco I : 4 pinion gears 24 spline and 3.54 ratio
Later Disco 1 onwards : 4 pinion gears, 24 spline, 3.54 ratio with multispline main pinion. (Rubber prop shaft coupling
4.7:1 All leaf sprung vehicles
3.54:1 All coil sprung vehicles
There are other ratios like 3.8:1 and 4.1:1 and can be found on some rover cars. Diff conversions to change gearing are possible.
This diff must not be confused with the so called "Wolf" diff which is also completely removable from the axle but it has a much shorter nose (pinion shaft) and is stronger than all the rover versions. It is fitted to some late model Defender 110 and 130 models. It is the same as the Discovery II diffs, which have one in the front and one at the rear.
You can get ARB lockers for these too ! Ratios: 3.54:1 only
Front and rear on: All Series 2B Forward Controls, Series 3 "1Ton" models, Forward Control 101, Some heavy duty 110s. It is also fitted to the rear of all Series 3 109" rear, 110 and 130 Rear
The Salisbury diff is much larger than the Rover unit.
5.7:1 (I think) in the Forward control 101 only (With HUGE sideshafts) 4.7:1 in the Series vehicles 3.54:1 in all coil sprung vehicles
You can also get ARB lockers for these.
ENV diffs are very rare and were used only on Forward Control 2A and early 2B - these diffs are also fully removable like the Rover models but they are massively strong with huge side shafts. They are available in standard Series land rover width and there is also a wide version as fitted to the early Series 2B Forward Controls.
They are easily identified by their big round ball appearance vs the sqaurer profiles of the Rover Salisbury diffs
The Millbug uses these axles in the narrow form.