Holden Astra Gearbox & Transmission Problems

The jerk when you select reverse sometimes is definitely worth having diagnosed properly as it shouldn’t be that way. Scanning the car (which I’ll presume the dealership did to arrive at its answer) doesn’t always show up all faults, so just because the computer says there’s nothing wrong, doesn’t mean there isn’t. There are plenty of reasons for a car to jerk into a particular gear, but the good news is that the Astra uses a conventional, torque-converter automatic, not one of the vastly more troublesome double-clutch units.

Your second problem, however, may not be a problem at all. In fact, the gearbox in the Astra is smart enough to know that you’re coasting down a hill and will actually shift down a gear or two to take the strain off the brakes while still maintaining your speed. As it shifts down gears, the engine revs will rise; that’s absolutely normal and part of the way the car is designed to operate.

You could argue the semantics of what is and isn’t a major failure till the cows come home and still not get any joy. But while I’d still be talking to the dealership, I’d also contact Holden’s Customer Service department and explain the situation to see if it will overrule the dealership’s call on this. The number to call is 1800 46 465 336.

Meantime, if the car is fixed and working properly, what’s the problem? You could get a brand-new car and have exactly the same thing happen, so where do you draw the line on what’s acceptable and what’s not? Had Holden refused to fix the car or done a botched job that still left the car with problems, it would be a different story, but if the car is back to brand-new, I would consider the problem to be solved. I’m tipping head office will see it the same way.

The transmission in the Astra is a conventional torque convertor unit, the one that gave the trouble in the Cruze was dual-clutch manual/auto, a different ’box altogether.

Rather than an internal transmission problem, this is probably a simple case of loose fittings where the selector meets the gearbox or even where the selector pivots inside the centre-console. The moving parts inside this mechanism can wear over time and lead to sloppiness in the shift lever itself. You can remove the centre-console panels and see for yourself if there’s excess play or movement in the connections. The fix might be new bushes or guides, but it shouldn’t be a huge job.

It isn’t a common problem, as it is on the BA/BF Falcon, but it is known to occur on the Astra. Because it has only done 92,000 km I would approach your dealer, and Holden, and request their help in covering the cost of the repair even though it is strictly out of warranty.

Yes, it can be rebuilt or replaced and an automatic transmission specialist would be able to do that for you. Cost for the job would be around $2000 to rebuild or replace the transmission on a changeover basis.

For a start, it’s never a good idea to drag a car anywhere with the wheels, hand-brake and steering locked. You can damage anything from the transmission, steering column, driveline and even ruin (flat-spot) the tyres.

If the clicking noise when you drive it wasn’t there before, then a mechanic would suspect that there’s been damage done to the front driveshafts. This would be consistent with the car being forcibly dragged along the ground. If you’re worried, have a mechanic check the car over and send the repair bill to your (now possibly ex-) housemate.

That's a tough one, but you would have to think it's external to the transmission given it's twice been replaced. It could be a number of problems, from a speed sensor, the gear position switch or the ECU. The best thing is to get it to an auto transmission specialist and have it checked.

When you look at how the Park setting works in an automatic transmission, you can see how this could happen. Basically, Park is engaged by a small pin that (typically) slides into the transmission’s output shaft and locks it, preventing the shaft from turning and effectively locking the drive wheels.

The problem is that the Park pin (also called a pawl) is almost comically small for the job it has to do. The point being that Park pawls have been known to fail, at which point, the car will be free to move if the park brake isn’t applied.

Best practice when parking an automatic car is to stop where you want to park, but leave the transmission in Drive and apply the foot brake. Then apply the park-brake, take your foot off the brake and let the park brake take the weight of the car. Then select Park. You’ll still have the security of being in Park, but you won’t have the car’s weight resting on that little park pawl.

You might be lucky and simply have a low transmission fluid level thanks to a leak, or perhaps even a selector that is not properly connected to the transmission.

But the fact that the transmission works in Reverse but not Drive suggests something internally wrong. You could be looking at a broken torque converter, failed clutch or band, a faulty pump, blocked valve body or even a broken gear set. A transmission specialist is going to be your best bet here.