What to do with my Hyundai i30's gearbox?

I have a 2015 Hyundai i30 diesel 1.6 (90k on the clock). It has been very reliable and I've spent very little money on it outside services etc.

Now, when I am changing gear from third to fourth, I am getting a slight grinding noise and also resistance. I spoke to my mechanic, and he does not want to touch the gears and recommended to go through Hyundai to do this.

He also advised it may be time to do the clutch while they're doing the synchromesh. Google also advises to do the flywheel while there. What would your opinion be? Should I spend the money now to replace the car or these parts? I have been avoiding those gear changes but I'm now getting some resistance between fifth and sixth as well.

Rose (Cork)

Mar 2026 Filed under: gearbox

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Expert answer

Hi Rose,

I would expect it to be prohibitively expensive to open up the gearbox and replace parts of it, and I certainly would be worried about what else is going to go wrong in it. If you're intent on keeping the car, perhaps talk to your mechanic about replacing the gearbox instead of taking it apart. There is some risk in buying a second-hand gearbox, so ask about sourcing a reconditioned one with a warranty instead.

And yes, it always makes sense to replace a clutch if the gearbox is off in any case. Same for the dual-mass flywheel.

Shane O' Donoghue - Complete Car Advisor