Tyre Pressures

dmiller555 replied on 10/01/2017 15:17

Posted on 10/01/2017 15:17

I have two questions:

I wonder how many with caravans change their tyre pressures between towing and not towing?

I ask because the recommended tyre pressures for my VW Passat varies between 33psi all round for two people to 36 front and 41 rear when fully laden with 4 people and luggage, which is quite a difference.

I have little idea what will constitute correct pressure when towing with two people plus luggage in the car and 75kg noseweight so I'm currently using 35psi front and 40psi rear, does that seem about right?

 

MollysMummy replied on 16/07/2019 00:29

Posted on 15/07/2019 21:23 by Michael Lyon

I think many folk are forgetting that the front tyres need the max pressure too .. there's a very heavy load on them when breaking and that's when I want best grip.  So, please suffer a slightly more taught ride and be safe.  It might also improve your mpg.

Posted on 16/07/2019 00:29

 ..... braking 😉

Cornersteady replied on 16/07/2019 16:41

Posted on 15/07/2019 21:23 by Michael Lyon

I think many folk are forgetting that the front tyres need the max pressure too .. there's a very heavy load on them when breaking and that's when I want best grip.  So, please suffer a slightly more taught ride and be safe.  It might also improve your mpg.

Posted on 16/07/2019 16:41

actually over inflated tyres have less grip and therefore less stopping power and also lead to more wear in the centre.

ocsid replied on 16/07/2019 19:34

Posted on 16/07/2019 19:34

IMO, the really important aspect of increasing, particularly the tow vehicle's rear tyre pressure, is to increase the overall lateral stiffness.

This stiffness being a fundamental "driver" in improving the whole unit's stability.

The odd extra sub 100 kgs load added is of relatively little relevance, that's only the value of a single fat person on the rear seat.

MollysMummy replied on 16/07/2019 19:44

Posted on 16/07/2019 19:34 by ocsid

IMO, the really important aspect of increasing, particularly the tow vehicle's rear tyre pressure, is to increase the overall lateral stiffness.

This stiffness being a fundamental "driver" in improving the whole unit's stability.

The odd extra sub 100 kgs load added is of relatively little relevance, that's only the value of a single fat person on the rear seat.

Posted on 16/07/2019 19:44

100kg = 'fat'? surprisedsurprised I'm not far from 100 (maybe 95) but am far from fat! tongue-out

Tigi replied on 16/07/2019 20:35

Posted on 15/07/2019 21:23 by Michael Lyon

I think many folk are forgetting that the front tyres need the max pressure too .. there's a very heavy load on them when breaking and that's when I want best grip.  So, please suffer a slightly more taught ride and be safe.  It might also improve your mpg.

Posted on 16/07/2019 20:35

Its interesting to note tyre pressures on a current Volvo XC60 are 1-3 passengers 230 back and front, 3-Max load is 270 back and front including towing and an ECO Pressure is 270 back and front (disregard no units). My point being it suggests that there is no reason why you shouldn't leave tyres at your towing pressure whilst away, the only negative effect is the harder ride.

Dorset Diver replied on 16/07/2019 20:55

Posted on 16/07/2019 20:35 by Tigi

Its interesting to note tyre pressures on a current Volvo XC60 are 1-3 passengers 230 back and front, 3-Max load is 270 back and front including towing and an ECO Pressure is 270 back and front (disregard no units). My point being it suggests that there is no reason why you shouldn't leave tyres at your towing pressure whilst away, the only negative effect is the harder ride.

Posted on 16/07/2019 20:55

I have no idea what your figures are (270 PSI would seem a bit high undecided) however, if the XC60 is similar to the XC70 I have two suggestion.  I always run my tyres at the eco pressure as the ride is just a little firmer but the handling is significantly improved.  I have also, upgraded my tyres from the original Continentals to Michelin Cross Climate.  These have a higher load rating, they are very slightly stiffer and also help to improve handling, plus if you are a tugger they add to the cars overall load rating.  

MollysMummy replied on 16/07/2019 22:23

Posted on 16/07/2019 20:35 by Tigi

Its interesting to note tyre pressures on a current Volvo XC60 are 1-3 passengers 230 back and front, 3-Max load is 270 back and front including towing and an ECO Pressure is 270 back and front (disregard no units). My point being it suggests that there is no reason why you shouldn't leave tyres at your towing pressure whilst away, the only negative effect is the harder ride.

Posted on 16/07/2019 22:23

The last time I up'd my tow car's tyre pressures I nipped into town on the increased pressures  ...... it was all over the place, verging on dangerous. I just leave my tow cars tyre pressure on the min now