LT230 Transfer Box
LT230 Transfer Boxes - R type & T Type
The LT230 series Transfer Boxes were introduced in 1983 with the LT77 5 Speed Gearbox range. The first boxes were known as the LT230R. These were updated in 1984 with a change to the Intershaft and Intermediate cluster to enable stronger Taper Bearings to be used. These later boxes are known as "T" type boxes (LT230T). Although there are some common parts to the two types of boxes there are some items that are now either unavailable or expensive to obtain. The good news is that the LT230T type can be fitted as a unit in place of the original LT230R. This also makes good sense for subsequent repalcement of spares. Check our picture below for location of Serial Number to assist in identification.

The Serial number of the LT230 Transfer Box should be found either on the bottom side above sump by drain plug or sometimes on the end face. See the examples above.
The LT230 unit has a serial number consisting of a prefix, 6 digit number, and suffix. This serial number will determine the type of box & ratio. The suffix will determine the approx date of manufacture and gear design used. Below you will find a table showing most of the common variations.
LT230 Transfer Box Serial Numbers
| Prefix |
Type | Ratio |
Typical Applications |
| 12D |
R | 1.667 | |
| 13D |
R | 1.410 |
|
| 14D |
R | 1.003 | |
| 15D | R |
1.192 |
|
| 20D | T | 1.667 |
Defender 4 Cyl Non Tdi |
| 22D |
T | 1.410 |
Defender 4 Cyl bar 2.5 Diesel Nat Asp. |
| 25D |
T | 1.410 |
Defender 110 V8 With LT85 Gearbox |
| 26D |
T | 1.003 |
RR Classic with 3 speed Chrysler Auto |
| 27D |
T | 1.192 |
RR Classic up to 1985 |
| 28D |
T | 1.222 |
RR Classic 1986 0n & Disco 1 |
| 29D | T |
1.192 |
Defender 90 V8 with LT85 Gearbox |
| 32D |
T | 1.222 | 4 Cyl & V8 3.5 fitted With LT77S Box |
| 34D |
T | 1.410 | Discovery V8 & 2.0 Mpi |
| 36D |
Q | 1.211 | Discovery |
| 37D | Q |
Discovery |
|
| 38D |
Q |
1.211 |
Defender V8 4.0 |
| 40D | Q | 1.211 |
Japan / South Africa |
| 41D |
T | 1.211 | Disco 2 With Diff Lock Stud |
| 42D | T | 1.211 |
|
| 43D |
1.410 |
Defender TD5 |
|

