synchro problem?

hey guys,
sorry if this isnt the right place to put this but hey, worth a shot right?
i have a '94 2.7 diesel navara and she runs like a dream boat, however there is a small problem with her 3rd gear. every now and then when i shift up or back down into 3rd there is a crunch. most commonly in speeds excess of 40km/h. sometimes this crunch is quite violent and trys to refuse the gear and has spat the gear back out of several occasions.
this is my first car and im blindly proud of it, i just want her to be running in top health. my dad says its probably a synchro problem but doesnt know if its doing any damage. ive been driving it for a few months now and it doesnt seem to be getting worse, ive just been trying to avoid going into 3rd above 40ks.
so now the point of my rant, to your experienced fourby-ing ears, does it sound like a problem that is going to get serious?
cheers guys,
tom

How many km's ?

The TD27 gearbox is not the strongest, between 200,000-300,000km's the gearboxes need rebuilds.

Other then that, good luck with the Nav.

There a great vehicle.

Dave.

I doubt it will do any serious damage quickly, but it's not going to get better by itself. At some stage you will need to have the gearbox replaced or repaired.

In the meantime, don't drive in third above 40 Navaras are great utes, but not designed to race.

Welcome to the forum, and yes, this is the right place to post this.

its on about 280000 and judging by the condition of the car in general when i bought it, it has never been serviced, or at the very least cleaned.
i do try to keep the gear changes in third to a minimum, its mostly just for compression braking.
thanks for the welcome and the advice, glad to know i have somewhere to turn to for advice for my pride and joy.
cheers