Toyota HiAce Gearbox & Transmission Problems

There’s a very good chance that your problem concerns the cable or linkage that connects the gearstick in the cabin with the actual gearbox. It’s very common for one cable or linkage to operate half the gears, and a second linkage to operate the rest. If this linkage has fallen off or become detached somehow, there’s no longer a physical link between the gearstick and the transmission selectors for those gears. At which point, it’s impossible to select the affected gears.

A quick check under the gearbox will confirm whether this is the case, and fixing it should also be a simple case of reattaching the linkage or possibly replacing a broken cable.

This does sound like an odd one, to be honest. It’s certainly possible to wear out a clutch in a very short space of time if you drive the car badly, but I’m trying to work out how a gearbox could fail at such a short mileage without there having been something wrong with it from the start. I’d also love to know why Toyota thinks the problem does not constitute a valid warranty claim.

Has the vehicle been used to tow exceptionally heavy loads? Are there any other extraordinary circumstances that makes Toyota think that the issue is a driver-abuse or neglect scenario?

I’d start by by-passing your dealership and contacting Toyota Australia’s customer service division. It might also be useful to have the damaged gearbox independently inspected by a specialist who might be able to pin-point the cause of the wear and help determine what happens next. If it can be shown that a component was faulty or simply failed too early, then I’d say you have a good case to pursue a warranty claim.

I’ll take a stab in the dark here and suggest that your van is a turbo-diesel (there was a petrol version offered as well, but the diesel was much more popular). If that’s the case, you could be dealing with a turbocharger that’s showing wear. Specifically, this is likely to be in the turbo’s bearing which will become noisy (and potentially emit a whistling noise) as the bearing starts to degrade. Turbochargers often spin at speeds of up to 250,000rpm, so the bearing really has its work cut out.

The clue to all this is that the vehicle starts whistling when you press the throttle; that is, when you place a load on the engine and ask the turbocharger to start providing boost. That’s when the worn bearing becomes loaded (and noisy). But you could also be looking at something much simpler such as an exhaust that has collapsed internally and is offering a whistling soundtrack, or even a loose piece of intake plumbing that is also allowing the air passing over it to whistle. Perhaps there’s something in the gearbox that is making a high-pitched noise as well. You really need to have the vehicle looked at by somebody who knows their HiAces and take it from there.
 

If it's got a bearing problem in the gearbox then you should assume it will get worse and eventually fail. If it is a bearing and the bearing disintegrates while you're driving it do some major damage and could end up costing you more. You probably should do it as soon as you can.

The best course of action is to fit a new clutch. It might not have had a new clutch fitted in its life so far and if so it's probably on its way out and will need replacing soon anyway.