# How much can I lower a Fiat Ducato by releasing tire pressure?

I'm renting a Fiat Ducato (5998 mm long, 10 m^3 payload volume), that according to the rental company is 2640 mm high, but, according to the FIAT specifications I could find, the only compatible value I found is 2520 mm when unloaded (and 13 m^3 payload).

A garage hallway where I have to drive is 2450 mm high in a short part of it with transverse beams. When loaded with 1200-1400 kg there are no problems, the van will surely fit. After unloading, it won't fit anymore.

How much can I gain by releasing pressure from the tires? on the way back only three people will be inside the van.

For information, after the garage I only have to drive down a ramp and few hundred meters to get to the closest place where I can pump the tires back to nominal pressure.

• "When loaded with 1200-1400 kg there are no problems, the van will surely fit" - is that just optimism, or based on some hard facts? If it is based on fact, the easy solution to the problem is just load up the van with more humans to get it out again. – alephzero Feb 16 '19 at 10:40

The simplest solution to all of this is "choose another van, not a Ducato".

If you really don't want to do that, first find which exact model of Ducato you are hiring. According to this official-looking source there are various models with unladen heights of 2254, 2524, 2539, 2764, and 2779mm.

The Ducato has been around for quite a long time and has had several styling changes in its life, though a van hired from a big company is likely to be a recent model. The heights may have changed by a few mm from one model year to another.

Trying to squeeze under a beam by letting the tires down is pushing your luck, IMO. You will probably find that for an unladen van, reducing the tire pressure to a ridiculously low level has very little effect, until some "straw breaks the camel's back" and the tire collapses completely, quite likely when you try to start driving the van.

Even if you only plan to drive a few hundred meters, driving round a curve could be enough to collapse a tire because of the sideways forces when you turn the steering wheel.

If you really want to try, push the van under the beam, and pump up the tires again immediately, with a hand pump if nothing else is available.

Measure the distance between rim and hardtop then divide by two - as you don't want the tire totally flat as it will get damaged... Might get damaged anyway.

Consider a different solution, such a a trailer with a low ride height...

Of course the other option is to load up with some heavy crap that needs taking out so you can leave...

• I can load it with 50 kg of stuff, but I doubt it will help much. – FarO Feb 15 '19 at 16:54
• 50kg is not heavy... that's just a hay bale in each hand... – Solar Mike Feb 15 '19 at 16:57
• Well it's 50 kg but there are also 3 people in the cabin... Anyway, if I had a 60 cm high ramp I would drive my Panda directly inside the Ducato. That's 750 kg, but I don't have any ramp that high. It would be cool though. – FarO Feb 15 '19 at 17:31

Do you have to drive into that garage? Can't you stop outside the transverse beams and unload there?

• If that blocks the entrance for other users for as long as it takes to unload and carry the stuff away, maybe not.... – alephzero Feb 16 '19 at 16:25
• Why not? Professional lorry drivers do that every day: If they can't drive onto the site safely, they'll unload on the street. – Hobbes Feb 16 '19 at 16:56