Superseded (sometimes incorrectly spelled superCeded) is a rather arbitrary concept related how car manufacturers identify their parts. Basically, a part that has been superseded means there is another part number that is newer, but it doesn't always mean that a superseded part is better or different. This could be for several main reasons:
- The part numbering system has changed (for example due to a stock management system change)
- The supplier of the part changed
- The design of a part has changed and is now supplied in place of the original. This may be due to increased specification to combat reliability issues or to allow fitment to a wider range of vehicle types
This means that trying to identify the differences between part numbers for the same application can be difficult, as it doesn't always mean that a superseded part is different, but sometimes it does. An obvious case of parts being superseded is the 300Tdi timing belt, which had premature wear problems and replacement parts were introduced in 1997. The tensioner pulley ERR1972 with flanged edges changed to LHP100860 without flanged edges. Changing the part number allows old stock to be cleared or discarded without being mixed up with existing stock
Confusion around superseded parts
A superseded part should mean that the part is a direct fit in place of the original, but sometimes once stock of an older part has gone (e.g. 20 years on), the newer part will be supplied in its place as there is still a supply chain for it. So if you order an old part number, you could get the newer one, even though the old part can be purchased. This is what can happen with brake discs - if you order FTC3846 then you may receive a part labelled SDB100980 or even SDB000330.
Land Rover can also change the part they supply without changing the part number. This is what can happen with bulkheads. If you now order a Td5 style bulkhead, you will get a hybrid made partially from Puma style panels, as the supply of the original style has dried up and presumably the tooling had been discarded. This could be why their price more than doubled in 2017! They should fit but there may be some structural differences (extra holes, etc.).
Suppliers can also change what they supply regardless of the correct numbering. CV joints are an example where there is little difference between ABS and non-ABS parts (the former having a serrated exciter ring on its circumference). The ABS CV joint is now always supplied even if you order the non-ABS part. The same has been seen with alternators, where AMR4249 has been supplied with an earlier style pulley even though that part number should include the complete alternator and pulley assembly which supersedes the older style.
The numbering system used by Land Rover started to change in later years of Defender production, moving towards LRxxxxxx type numbers which are a comparable style across all models and part types. This can be seen with Puma second row seats where the seat design stayed the same yet the numbers changed in 2012. However, sometimes this change did also include a switch of design whilst changing to this newer style numbering, as seen in the change of rear door glass from CQB000270 to LR042729. The former had a heated screen element row that passed under the high level brake light and slowly rubbed through. The later part routes the element around the brake light.
How do you know?
This can lead to all sorts of confusion whilst ordering parts - the one you order may arrive under a different part number or it may have the same part number and be a different design or manufacturer. The real test is to order Genuine parts that you should receive bagged and labelled, so that they can be compared with older or superseded known parts. This is where this site can help other Land Rover owners, as you can add pictures of parts, comments on parts and write reviews of the parts you receive. This will allow us to try and uncover what is actually going on in the part numbering system of Land Rover through the years.
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