I’m sitting at work one afternoon when the phone rings. My wife is on the other end, and says ‘I’ve just driven the Dmax out of the driveway, and it feels tight and then made a clunk’. My heart sinks. Great. Not even 40k on the clock and something’s gone bang.
‘Are there any lights on the dash?’ I ask?
‘Yeah, the squiggly lines one’ Sarah replies.
I have a quick think, and instantly realise what is most likely.
‘Is it in 4WD?’
‘I don’t know, how do I tell that?’
I explain to look down at the dial on the console, and sure enough, its been flicked into 4 Low.
After putting it back into 2WD, and having a short drive Sarah confirms it all seems normal.
I have a quick look after work, and confirm there’s no oil leaks or damage underneath, so perhaps we’ve avoided a disaster.
Just recently Oliver has taken a love to sitting in the front of the 4WD when its parked up, and I’ve always been careful to check that he doesn’t touch the 4WD dial. I guess he finally got it, and it nearly cost us a CV.
Thinking about it, the clunk would have been the vehicle going into 4WD, and I’m lucky Sarah realised so quickly something wasn’t right.
4WD on bitumen
On most 4WD’s, you can’t engage 4WD in either high or low range with the centre diff locked on solid ground without running the risk of breaking something. The reason is quite simple; as you turn, your wheels rotate at different speeds.
When you go around a corner the outside wheel turns faster than the inside. If you have locked the wheels together by way of it being in 4WD there is no room for slippage, which puts enormous stress on your driveline until the weakest thing breaks.
I know a few people who’ve broken CV’s this way – never engage 4WD on bitumen or hard surfaces unless you have a centre diff lock that you can keep disengaged (like many Land Cruisers, and Pajero’s).