I’ve got 40 all round and it rides ok and tyre wear seams to be pretty even so far.
Tyre Pressure 275/40/20
- Thread starter 9 Foot Shark
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- 275/40/20 tyre pressure
Look back up this thread to post #11
TheWandering
Member
Does anyone know what pressures to use on my 204 4motion swb? Mostly motorway driving.
It has a fair amount of extra kit on it - pop top, solar panel, Slidepod, etc.
Thanks in advance
It has a fair amount of extra kit on it - pop top, solar panel, Slidepod, etc.
Thanks in advance
TheWandering
Member
Leighton Vans have managed to get TPMS working now with their 20in wheels and have sent me a video with what look like rather high pressures they are using - 58psi all round.
TheWandering
Member
Correction - Uniroyal Rainsport 5 tyres.
I'd check the sidewall markings before putting those pressures in! A method seen used in the past goes like this;
1. Not max load rating of tyres and x4
2. Find out actual weight of van
3. Work out what 2 is as a percentage of 1
4. Note max pressure on tyre side wall
5. Set pressures to the same percentage of 3
Example
1. Tyre load rating 1000kg per tyre = 4000kg total
2. Actually weight of van 3000kg
3. 2 as percentage of 1 = 75%
4. Max tyre pressure = 40psi
5. Set pressure = 30psi (75% of 4)
Obviously this assumes the same axle weights, so to do this more accurately you'd need to use the same method but per axle.
1. Not max load rating of tyres and x4
2. Find out actual weight of van
3. Work out what 2 is as a percentage of 1
4. Note max pressure on tyre side wall
5. Set pressures to the same percentage of 3
Example
1. Tyre load rating 1000kg per tyre = 4000kg total
2. Actually weight of van 3000kg
3. 2 as percentage of 1 = 75%
4. Max tyre pressure = 40psi
5. Set pressure = 30psi (75% of 4)
Obviously this assumes the same axle weights, so to do this more accurately you'd need to use the same method but per axle.
And yes, axleweights are often not the same, so deviding simply by 4, gives to low pressure on one axle, wich you never must have. A bit to high is no problem, much to high gives bumpy ride and much much higher gives centrewear.
When I calculate it, I add 10% reserve to the acurate determined axleweight before doing the calculation.
And that determining real axleweight is the most tricky part in it all.
So reserve is for next.
1. Unequal R/L on the axle
2. Pressureloss in time
3 inacuracies in reading pressure and weight.
4. etc, etc.
The lineair calculation is not that bad. Official calculation leads to yust a bit lower pressure.
Once got hold of that and went running with it. Now use a saver one that comes closer to lineair calculation.
Also speed you use ( and wont go over for even a minute) in relation for wich speed the maxload of tyre is determined, is a factor.
Referencespeed for most tyres is 160kmph/99mph.
When I calculate it, I add 10% reserve to the acurate determined axleweight before doing the calculation.
And that determining real axleweight is the most tricky part in it all.
So reserve is for next.
1. Unequal R/L on the axle
2. Pressureloss in time
3 inacuracies in reading pressure and weight.
4. etc, etc.
The lineair calculation is not that bad. Official calculation leads to yust a bit lower pressure.
Once got hold of that and went running with it. Now use a saver one that comes closer to lineair calculation.
Also speed you use ( and wont go over for even a minute) in relation for wich speed the maxload of tyre is determined, is a factor.
Referencespeed for most tyres is 160kmph/99mph.
I wouldn’t let Leighton sell me a valve cap, 2 years ago they were happy to put 102 rated 19" tyres on T32’s.
I believe generally speaking on 20’s people put 36 all round or up to 40 if carrying a bit of weight.
On my T32 lwb I’ve run 40 rear and 38 front without issues for the past 3 or 4 years, when towing my caravan I run 44r 40f.
I believe generally speaking on 20’s people put 36 all round or up to 40 if carrying a bit of weight.
On my T32 lwb I’ve run 40 rear and 38 front without issues for the past 3 or 4 years, when towing my caravan I run 44r 40f.
TheWandering
Member
Thanks. Yes well as the story goes, I bought a van form then last November and between them and Slidepods they managed to let the vehicle out with a very long list of faults. It’s been 4 months getting them fixed. One of the issues was the TPMS which they disabled and said wasn’t on the van as they wanted to fit 20in rims.
I insisted I wanted it and now they say it’s finally working but I’m alarmed the video they sent shows such high recommended pressures. I used to run 40psi all round not approaching 60 psi as they seem to have programmed in.
I’m collecting the van tomorrow so I’ll be asking for 35-40psi to be programmed in. I just hope they can do that as I won’t run 40 and be told all day long I’ve got low tyre pressures!
TheWandering
Member
I agree. I ran that before.
Angus Macdonald
New Member
Just having to replace my tyres. I'm running pirelli 275/40/20 on rear and 245/45/20 on front with 40 psi and the front tyres are totally worn in centre so 40 psi is too high for me... Going to try 36 front and 38 rear for new tyres. I have a T32 204 dsg Kombi only carrying 2 x german shepherds..
Hope this helps
Hope this helps
I have those on the rears and do 40psi unloaded, 245/45's on the front at 40psi unloaded 10 width on the rear, 8.5 on the front. I put them up to 42 when on a roadtrip!
Have you got those tyres all round?
Have you got those tyres all round?
