Technical 1.4 16v gearbox swap 5 to 6 speed

[ConanDeDestroyer]

Hi everyone,

My voices in my head are telling me about swapping the 5-speed manual gearbox in my 2008 Lancia Musa (1.4 16v petrol, after FL) for a 6-speed one. I’ve searched the forum to see if anyone else has attempted this, but couldn’t find any relevant threads—so apologies in advance if I’m repeating a topic that’s already been covered.

Before diving in, I’d really appreciate your insights:

• Is this a plug-and-play swap?
• Will the ECU or wiring need to be modified?
• Are there any compatibility issues I should be aware of?
• Or is this heading into “custom work and duct tape” territory?

And most important question: are those 6 speed gearboxes worth it? I mean in a reliability point. My current 5 speed have about 270k and starts to develop problems with 1st and reverse gear, have 2 kilometers of slack on stick, sometimes it simply refuze to click in to gear. So I ll need to replace it soon. And the dillema: do I stick to 5 speed, or try to upgrade it to 6 speed? I did start to travel more on autobahn and reving to 3,5-4k rpm to have constant speed is hurting my wallet (this 1.4 doing 120 kmh is thirsty) and ears. So yea, that's the deal.

Also, sorry if this is a bit of a faux pas—I know this is the Fiat Idea section, and I’m talking about a Lancia Musa, (i feel a bit like cold war era spy trying to plend in, hello there fellow fiat owners) but since they’re essentially the same car under the skin, I hope I’m not causing a scandal here!

Thanks in advance for any help!