When it comes to tyre deflation, its pretty well accepted that its the right thing to do when heading off road. Today though, we’re talking sidewall punctures, and whether tyre deflation increases the chance of a puncture or not. Are you someone who lets your tyres down on a gravel road, or do you leave them alone regardless?
If I’ve already lost you, my apologies. When you head to a gravel road for an extended period, do you stop and reduce the air pressure in your tyres, or just drive at full, normal road pressures and not change a thing?
I’ve always made a habit of reducing air out if at least one of the below applies:
We’re on the road for more than half an hour
The road is corrugated and uncomfortable for me, any passengers or the vehicle
There are rocks that are likely to cause a puncture
Recently though, I’ve had more than a handful of people tell me that they don’t deflate their tyres at all on gravel roads, ever, because it increases your chance of a sidewall puncture, and you know what? They are partially right.
The reason they are partially right is that when you deflate air out, the tyres bulge more, and you expose more of the sidewall. If you happen to clip the edge of a sharp rock, it can theoretically cut your sidewall, or cause a puncture more easily.
I don’t disagree with this, but I do question how often this would happen, compared to the huge array of benefits of running lower tyre pressures in the first place:
Substantially reduced chance of a puncture through the tread
Improved ride comfort for those in the vehicle
Reduction of mechanical force applied to the 4WD, which in turn reduces wear and tear
Reduced damage to the track, in helping to smooth corrugations rather than make them worse.
I wrote a post a while back about bumping into two blokes on the Gibb River Road, who’d suffered more damage than I have ever seen on fairly stock vehicles, and when we got chatting, they said to me ‘we were told not to let them down as it increases the chance of a sidewall puncture’.
Well yeah, it might do, but had their tyres been let down they’d have a lot less damage done to their vehicles, and for the (in my opinion) very small increased chance of a sidewall puncture, I’d do it every day of the week.
Interestingly, I’ve never had a sidewall puncture. I’ve had a couple of punctures through the main tread and had a tyre blowout on our camper (which I suspect was from a failed valve stem overheating it), but never suffered a sidewall puncture, and we’ve done a huge number of 4WD tracks all over the country.
I wonder if this advice stems from old tyre technology, when punctures were more common due to lesser quality/technologically advanced tyres being used? Most 4WD tyres that you buy today do a seriously good job of avoiding punctures altogether, and I don’t agree with leaving your tyres at full pressure on gravel roads.
Despite this, I still hear people saying that you shouldn’t let air out of your tyres on gravel roads, because it increases the chance of a puncture. What do you reckon? What do you do?