T25 D4D Transmission Issues - 5Th Gear

[jrilev]

Hi all, new guy with a problem

Our 2004 85 kW D4D (1CD-FTV) 5-speed manual Avensis is developing a transmission problem:

When in 5th gear upon load transfer (accelerating - coasting - engine braking) the gear lever moves back and forth and slight vibration can be felt when shifting. All other gears are 100% OK.

I have checked the motor mounts and gear linkage cables and they are fine. When shifting from the engine bay (moving the gearbox lever/weight by hand) the 5th engagement feels a tad "loose", i.e. not as positive as the other gears.

I understand a thing of two about transmissions and to me it's obvious something is pushing the selector ring/hub axially back and forth. If this were a bad bearing, other gears would also be affected. I have read somewhere, there were assembly issues at the plant and the actual 5th gear lock nut was not tightened to specs. This allowed one of the 5th helical gears to move about and wear the shaft splines in that location along with other associated parts of the 5th synchronizer hub (slider, engagement dogs, synchro rings).

I have found the 5th gear hub is located "outside" of the transmission, behind a metal cover that can be accessed from the LH wheel arch. This means all problematic parts should be replacable without removing the trannsmission from the car providing the shaft itself is not worn past limits (in which case a complete tranny rebuild is pending).

I want to address the issue before it deteriorates that far.

Does anyone have any experience with this problem?

[CroAvensis]

I'm from Croatia and my english isn't so god.

Sorry if I make mistake in writing.

In that case you should change oil inside gearbox and it will probably be OK.

[JAPCAR]

In that case you should change oil inside gearbox and it will probably be OK.

Can you explain how the oil affects just 5-th gear no other ones?

Generally, if somebody knows how old oil affects changing gears. I mean what happens inside?

[CroAvensis]

That happens becase the 5th gear is the most loaded gear in transmission and because of her place in gearbox.

I've alredady fix that problem by changing oil in gearbox.