When a YouTube Star's Caterham Hits a Differential Snag: A Rebuild Story
It's not every day we get to work directly with YouTube personalities, but recently, we had the unique opportunity to collaborate with James from the popular channel 'ACaterhamCalledFern'. James brought his Caterham's differential to us for a rebuild, a project that not only piqued our interest but also highlighted a widespread issue among Caterham vehicles from the early 2010s to around 2018.
The core of the problem lies with the carbon plates within the BMW-style differentials used in these vehicles. Over time, these carbon plates fail, leading to the malfunctioning of the Titan Limited Slip Differential (LSD) — best-case scenario, it stops working; worst-case, it causes complete differential failure.
Identifying the Issue
For those who suspect their Caterham might be affected, there's a straightforward way to check. Look for a differential casing that's black with a 'cage' around it, as opposed to a silver casing with 'ribs'. Vehicles from 2012 to 2018 fitted with a factory LSD are most susceptible, though there are exceptions, such as purpose-built race cars or those that have already undergone repair through a warranty or a specialist like us.
Symptoms of LSD Failure
The hallmark of a failed LSD is a lack of locking action. This means difficulty in spinning wheels together, especially noticeable when trying to power out of a corner. Other symptoms include clunking sounds or a slack when pulling away. However, it's crucial to remember that such noises aren't definitive signs of LSD failure, as they can occur even in healthy systems.
The Solution
As showcased in James's video, the remedy involves replacing the carbon plates with a sintered plate kit, which includes nearly all internal components except for the ramp blocks, output gears, and spider gears. Neglecting the issue doesn't make it disappear; worn carbon plates can lead to further destruction, necessitating a complete differential replacement.
Why Did This Happen?
Initially chosen for their smooth operation in F1 vehicles, the carbon plates used by Titan and Caterham were not durable for the longer servicing intervals of regular road use. This led to the adhesive failure and the eventual peeling off of the carbon weave from the metal plates, necessitating a switch back to more reliable sintered plates.
Despite the bad reputation acquired by Titan LSDs due to this issue, it's worth noting that with the correct sintered plates, these differentials perform exceptionally well, even in 400hp championship-winning race cars.
Looking for Alternatives?
For those considering a brand-new differential instead of a rebuild, options like Tracsport, Drexler, and Wavetrac offer various benefits. Each has its unique features, catering to different driving needs and preferences, from quieter operation to customizable setups that match the Caterham chassis.
Our Recommendation
When asked for advice, we often lean towards the Drexler differential for its customizability and reliability. However, for those prioritizing quiet and smooth road driving, the Wavetrac stands out as an ideal choice. Yet, if your Titan differential is salvageable, like James's, we recommend going for the rebuild. It's a testament to the durability and performance that can be achieved with the right care and expertise.