Xantia Gearbox

[froggy]

Hi, my S1 Xantia manual gearbox....I have just noticed resistance when trying to get fifth gear,,,,,, the other gears are ok. any help will be gratefully received, many thanks Terry.

[wurlycorner]

Don't know of anything directly relevant to Xantia boxes (if there are any common 'known causes' on them, I'm sure someone will be along shortly) but...
These things are normally caused by either a bent fork inside the box, stiff part of the linkage that operates only for fifth, dragging clutch (not disengaging properly), worn syncromesh or low box oil level.
The last one is the simplest to check, so start there

[ekjdm14]

Isn't an unwinding bolt/collar a known cause of 5th gear issues on some boxes? Not sure what variant, but the fastener in question slackens off over the miles and eventually starts causing 5th to jump out of gear. If it's this, you can probably get away lightly with removing the side plate and retorquing and staking. (I've heard that if it jumps out of 5th once or twice you MIGHT save it, any more and the 'box sustained damage).

Unsure if this is possible with your box as it's "only" difficulty in selection not jumping out, but if so at least it's been caught early! As mentioned though check the oil level first off (PSA manual boxes seem to live long lives even on low oil, but definitely could be a symptom)