Stilo abarth gearbox issue

[abarthmarv]

The problem is 4th gear dont wanna play anymore, it goes into gear ok and can be used when slowing down off throttle but as soon as power is applied bang out it comes, wont even stay in gear if held in by hand. Anyone else had this problem??
So ill need a new box, but i dont want another 5speed, ive seen on this forum about a 6 speed box that fits from a lancia thesis(same engine), has anyone any knowledge about this?
From doing a few searches, stilo abarth gearboxes are scarce to find, only one company i found in holland that has a 6 speed gearbox from a thesis.
Any help is greatly appreciated!!
Ive owned the car from brand new and therefore want to keep her, its got just under 77000 miles on her, its a 54 plate. Am going to hopefully get her fettled into pristine shape along with new wheels(ideally 19"), full system exhaust and panel filter. Thanks for taking the time to read.

 

[s130]

I thought all the Stilo Abarths had the Selespeed Tiptronic box (well mine did). Holding the gear lever in the "shift up" position won't provide any mechanical force to hold a gear.

You could try resetting the system. This is done by opening and closing the driver's door at least ten times. I think this is documented in the owner's manual. What I can't recall is if you have to have the ignition ON or OFF when doing the procedure.

 

[abarthmarv]

Mines a 5 speed manual not selespeed.

 

[F123C]

Have you enquired about having your present gearbox repaired?
Given that you've had the car from new and it has covered only 77k mls, perhaps the best option would be to fix what you've got?
You could even do the job yourself if you're reasonably proficient in car repair.

As a former Fiat Mechanic, I'd suggest that all that likely needs to be renewed on your gearbox would be the mainshaft 4th gear, 4th gear synchro sleeve + synchro ring, and if worn/damaged, the 4th gear selector fork - add in gaskets/seals and the bill would probably be less than the cost of a (hopefully) good s/hand 'box. Additionally, I'd replace any even slightly suspect bearings and 2nd and 3rd gear synchromesh rings to avoid possible future problems.

It becomes a fair bit more costly if you have to pay someone's labour charge, but you could save a significant amount if you can remove/refit the 'box yourself and just have them do the rebuild.

Al.