5th gear slipping out - new gearbox?

[bhagatsingh]

Vw t25 1.9 watercooled
1986

Just returning from a drive to Amsterdam. Halfway there 5th gear kept slipping out on acceleration! couldnt even hold it in 5th manually. Had to drive slowly in 4th halfway there and all way back!

Looking around the forum there seems to be 2 opinions -
1. New gearbox
2. Change the gearbox oil.

What do you guys think? If I go for 1 what would you recommend would a golf (any other model) gearbox be a good idea? Or a reconditioned one?

Any advice much appreciated.

Think I need a rest now!

[CovKid]

I doubt very much that changing the oil will cure that. Ask Aidan - he might know although sadly I don't think he actually fixes 5 speeds. Sounds like a selector problem but has the gear linkage been checked over?

[bhagatsingh]

Hi

Ive had look underneath to check linkages and play around with gears seems fine...

You think its a new gearbox then?

Thanks for help

[CovKid]

I'm not the one to advise on whether its in need of repair/replacement but 5-speed boxes are like gold dust.

[ZsZ]

4-5 synchronizer hub fell apart. It is time to get it to a repairer.

http://www.gowesty.com/tech-article-details.php?id=78" onclick="window.open(this.href);return false;

[Aidan]

I do repair 5 speeds, lots of them, and lots of 4 speeds and lots of syncro boxes and front differentials, it's what I do

if the linkage has been ruled out of the equation then loss of top gear is usually due to mainshaft bearing displacement and/or wear and once it starts to happen every time it slips out of gear the dog teeth on the gear and the synchro slider wear so that they will no longer hold gear at all and it will require a replacement 5th gear and synchroslider as part of the rebuild
there are other possible causes, damaged slider bearing or synchrohub failure, either way expect a proper rebuild on a five speed with this fault to be more than a grand done right

changing the oil will not fix anything, nor will putting in an additive

[CovKid]

Apologies Aidan - mixing up Aircooled boxes with 5-speeds I think.

[bhagatsingh]

Thanks everyone! Oo just dropped a load to replace the engine last year. Gonna have to take stock of finances!? Will message you in due course about it aiden if that's OK? Whereabouts are you based?

[R0B]

Its Aidan not Aiden Hes not keen on the wrong spelling.

[bhagatsingh]

Aah sorry! Need to sleep! Also got it you're in wales. Thanks a lot for all your help.