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iRacing has announced a new hotfix for the 2026 Season 4 build, and the biggest change focuses on the recently released Caterham Academy and 420R. The update is scheduled for September 11 and addresses an issue with the rear suspension that could have a noticeable effect on how both cars handle.
The Caterhams have already become some of the most talked-about additions from Season 4. Both are lightweight, lively cars, although the faster 420R has received some criticism for how quickly the rear can break away.
According to iRacing, the damage settings on both Caterhams were preventing the rear axles from moving through their full intended range. The hotfix changes those settings, which iRacing says will fundamentally improve the handling of both cars.
The same issue could also make it difficult or impossible for the Caterhams to pull away from their pit boxes in certain situations. That should be resolved by the update as well.
Personally, I have really enjoyed the Caterham Academy. It is super fun, very slidey, and generally behaves the way I would expect a lightweight road-based Caterham to feel. You can move the car around without every bit of oversteer immediately turning into a spin.
The 420R has been more difficult to get along with. It is obviously supposed to be faster and more demanding, but the rear currently feels like it can snap away a little too easily, particularly when transitioning into the exit of a turn
If the rear axle was not operating through its intended range, this hotfix could potentially make those transitions more progressive. We will have to drive the updated car before knowing exactly how significant the difference is.
The update also fixes two simulator crashes. One could occur while scrubbing through replay controls, while another could happen when minimizing the simulator.
It is a small hotfix overall, but the Caterham adjustment is an important one considering both cars only arrived with the Season 4 build a few days ago.
The Caterhams have been a great addition to iRacing so far, especially the Academy. The 420R still feels like it needs some refinement, and hopefully allowing the rear suspension to work as intended helps calm down some of its more sudden behavior.
The hotfix arrives today on September 11 at 12:00 UTC, so we should know pretty quickly whether the change makes a meaningful difference.
