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QCAN any adjustments be made to ensure smooth changes in the four-speed automatic transmissions fitted to VZ Commodores? I often notice a light but abrupt clunk when the transmission shifts up or down between second and third gears. It is most apparent when accelerating up to 50-60 km/h. Compared with the other seamless gear changes, there seems to be a slight hesitation before the next gear is taken up. The dealer I bought it from told me there was nothing wrong with it, that it was normal, but I’m not satisfied and I’m thinking of taking it to an auto trans specialist. Is this a good idea or should I just turn the radio up?
Steve Parks, email It could be a faulty shift solenoid or a problem with the throttle position sensor. Take it to an auto trans specialist who should be able to diagnose the problem for you.
a car is on a slight gradient with the auto in drive and your foot off the brake should it roll backwards or hold on the gradient? I have had a VP and currently have a VS Commodore and neither would roll backwards with an idling engine, but a VE recently bought by a relative does. Is this normal with a VE Commodore, or is it a fault?
Ken Dutch, email It depends on the gradient, the idle speed etc., but generally an auto will sit on a slight gradient without rolling back. The idle speed could be a little low. But I wouldn’t be concerned about it if it does roll back. It shouldn’t have any effect on take-off when you’re out driving and have to stop on a hill.
AMworried that the clutch in my Peugeot 308 2.0-litre diesel is starting to slip after 28,000km. It happens only on warm days when the engine is warm, going uphill in fifth or sixth gear at peak torque at 2000 revs. I told the dealer at the last service, but they could not replicate it? Does anyone else have this problem?
Colin Prasad, email Yours is the only complaint we have received to date, so I would suggest it’s not a widespread issue, if indeed is an issue. To have a clutch slipping at such low kilometres is very unusual and I would be sceptical about it.
PLUG TOO TIGHT
previous owner of my 2007 Nissan Navara D40 STX 2.4-litre turbo diesel had it serviced by an independent mechanic, but since I bought it I have had it serviced by a Nissan dealer. At the 55,000km service I was informed that the sump plug had been overtightened and the thread had pulled put, and an oversized plug had to be fitted. At the next service I was advised that the sump needed to be replaced at a cost of $470 plus fitting. The head mechanic at the dealership said that this has happened before on vehicles serviced outside the dealership. But when I asked the mechanic who’d previously done the servicing about helping with the cost of replacing the sump, he said he had experienced the same problem with Navaras serviced at the Nissan dealership. I was wondering if this may be a fault and perhaps should be covered by warranty. Have you heard of this before?
Gary Pappalardo, email It can happen if someone overtightens the sump plug. The thread can be damaged and distorted, but the usual way of fixing it is to use an oversize plug, as has been used on your car. The thread can sometimes be
Slow uptake: a Commodore owner hears a clunk in his automatic transmission.