[marshy]

I've just bought a i30 SE NAV 1.6 Blue Drive and so far I'm loving it.  Something that is niggling me though is that when I'm doing 30 and change into 4th the engine sounds like it is struggling slightly.  It's not terrible but the engine sounds louder.  We have a 1.7 IX35 and my previous car, a 1.9 Golf, don't have this issue but I don't know if it's because it's a smaller engine.  Does this sound right to people?  Could there be a problem with my 4th gear?

[Dazzler]

Welcome Marshy,  The FD series Diesel maunal didn't seem to like 4th gear under load around 1500 RPM especially in the 5 speed 2007-2010 version. I'm guessing you are talking a newer version than that though?  The models have different designations in Australia. 

[marshy]

Hi Dazzler, It's a 2017but I'm not sure what series engine is in it.  Where can I find this?

[nzenigma]

According to UK Car buyer specs, you have a GD model 1.6 litre diesel (turbo? not stated) with a 6 speed manual gearbox.
I think you need to increase the Revs prior to changing gear.