2014 Defender 110 - Tyre Pressures

[specwarop]

Hey guys,

Just trying to find out what tyre pressures I should be running on my 2014 Defender 110, with the standard Continental Cross Contact AT tyres.

The placard inside the drivers door says 36psi front and 48psi rears, unloaded, for road driving.
However, in the process of pumping the front tyres, I find they are already 42psi in the fronts (with 1000km on the clock - so thats what the dealer put in) and 44psi at the rears...

Just after some clarification, as I noticed the rears appeared a bit flat.

Regards,

[AndyG]

Well the placard is the legal arbitrator, does it agree with the Owners manual.

The Dealer was probably a 18 year old apprentice thinking about his coffee break.

But a question i have been pondering, which tyre gauge to get that will give me a accurate measurement, leaning toward the VDO tyre gauge.

[specwarop]

Well the pressures I read were from the BP air hose. Accuracy definitely in question...
I should buy my own, but a good one is what - $100? Major deterrent...

[AndyG]

I was looking at them today, $30 will get you the vdo on ebay
And /or look for a servo that has an electronic gauge. They are more accurate.

[specwarop]

How does their quality compare to the likes of ARB?

[BadCo.]

To answer the original question, I'm lazy and just chuck 35 front and back for highway (stock 7.5R16). The placard in the Perentie had crazy high figures, 40 front 55 back from memory. Probably fully laden though.

I will be interested to see what others use. In my Subaru Legacy I have 32 all around, and my motorbike had 28 front, 32 rear, for reference.

[PAT303]

I run 34 front 30 rear with 7.50x16 empty in the Tdi,36front 32 rear with 235/85x16 in the TDCi empty.If you aren't loaded defenders drive better with more front less rear IMHO. Pat

[voltron]

The tyre pressure question has been driving me nuts lately. If I lower my pressure below 40 at the rear I find it effects the shocks dampening ability and the car gets the side to side body shake. If I keep them high, the dampening problem is solved but then the harshness of the standard shocks starts to show its head, less so since I installed the Billsteins. I like high pressure because the car is more stable but unfortunately more jarring to the body.

But all the suggested pressures provide a nice ride for comfort.

[Longtimer]

I have tended to ignor the manufactures spec' when it comes to tyre pressures, and treat them as recommendations for the uninformed.

What I do is set the pressures at a pressure that provides even wear across the tyre. This is easy to do when the tyres are new, as the little moulding spikes show your wear very quickly. My Disco has 235/70 R16's. For even wear, I run 38 in the front and 40 in the rear. This can be verified with a good verier caliper, by measuring the tread depth across the tyre. When I picked up my 90 the other week, it had already done 50Km. So it was too late to check it visually. I will get out a vernier on the weekend and start to take some measurements. It take 5 minutes. Then each weekend I will compare the readings, and adjust accordingly until I am happy with the wear pattern. As my spare has never touched foot on the road, I have a datum to work from if required.
If I am going on a long trip and loading up, then I increase the tyre pressures by 2 PSI all round. This takes care of the extra loading.
travelling at different speeds does make a slight difference to the wear pattern. going slow wears the outsides. Going fast wears the centre. All we can do, is aim to get a pressure that provides an even wear for our normal driving habits.If you live in the city and normally drive around at 60 kmh, then work out what pressures give even wear for those driving conditions. Then for your trips away at 110 kmh, work them out separately. I would suggest starting at 2psi high than normal.


Even wear, relates to even pressures being applied to the road across the entire width of the tyre. This provides for maximum grip and stability.


Chers,

Phill.

[noyakfat]

In my limited Puma travel so far (only 5,000km on the clock, from new), I've not been on any holiday trips. I have not been loaded up yet, so just run 36 psi all round when on the bitumen and daily driving.

Off road into the Brindabellas etc I've stuck to 18 psi all round and low speeds. Goes well :)

[PAT303]

The tyre pressure question has been driving me nuts lately. If I lower my pressure below 40 at the rear I find it effects the shocks dampening ability and the car gets the side to side body shake. If I keep them high, the dampening problem is solved but then the harshness of the standard shocks starts to show its head, less so since I installed the Billsteins. I like high pressure because the car is more stable but unfortunately more jarring to the body.

But all the suggested pressures provide a nice ride for comfort.

I don't understand the side to side body shake,I've never driven a defender that does anything resembling that,the opposite in fact,coming home from driving LC's at work I had to get used to my defender driving straight and turning with the wheel,LC's turn as an afterthought. Pat

[voltron]

I don't understand the side to side body shake,I've never driven a defender that does anything resembling that,the opposite in fact,coming home from driving LC's at work I had to get used to my defender driving straight and turning with the wheel,LC's turn as an afterthought. Pat

Maybe its my description of the symptom PAT but basically under certain circumstance the vehicle body as a whole will sway side to side, enough that my daughter can hit her head on the window if Im not careful enough over uneven terrain. This happens if my tyre pressure is lower then hard.

[tact]

The owners handbook and workshop manual for my MY13 DC ute says unladen should be 30psi front, 48 rear. (no tyre placard required in Malaysia)

Fully loaded: same 30psi front. 65 rear

That's all on the boost alloy wheels with 235/85R16 Conti Cross Contact tyres (same as OP)

So I am wondering how you guys in Oz get the mandated tyre placard stating much higher numbers!

I found 30/48 too rough unladen around the city and have been experimenting with 28/28 for the past few months. (I increase pressure with load, or on long high speed highway use).

[dromader driver]

I run 23/34 on the empty trayback around town. takes some of the banging and crashing out without the tyre temps coming up. SYD-BNE runs much higher closer to book figures. 7.50/16 Michelins:cool:

[Dockstrada]

All Terrain BF Goodrich 265/75R 16 I run 29 all round un loaded, 36 rear loaded nice plush ride and tyre wear is fine .

[Dockstrada]

I run 23/34 on the empty trayback around town. takes some of the banging and crashing out without the tyre temps coming up. SYD-BNE runs much higher closer to book figures. 7.50/16 Michelins:cool:


May give these numbers a go, how's tire wear and steering ?

[dromader driver]

sorry make that 28/34on the 7.50/16.

about 90 000k on a set of 4. Didn't get a bit more as one wheel bearing decided to have a holiday and it wasn't picked up early enough.

No probs with steering. :cool:

[isuzurover]

I run 38-48 psi on road. Depending on load and weather (higher pressures improve traction on wet bitumen).

I have slightly higher wear in the centre of the tread (not much), but it saves the lugs for offroad where they are needed - where I run as low as 7 psi.

I have stopped counting how many km I have done on my MTRs but it is >>60000 km and they are only half worn.

The Maxxis Bighorns are almost worn out at ~85000 km but have travelled coast-coast E-W 4 times and N-S once including the canning and gibb. In fact they have visited every state in Australia at least once (including TAS)!!!

[Jeff]

I have 235/85-16s and run 36psi all round unladen, although unladen includes an Outback drawer and a Kaymar tyre carrier, both reasonably heavy items. I recently bought a tyre pressure monitor from Jaycar, about $150 and on a recent trip to Cameron Corner I watched the tyre pressure as the tyres heated up, both at road and off road pressures and with the rear upped to 40 due to the load, the pressure increased 3-4 psi when hot, which I thought good. I ran 30/32 once I hit prolonged dirt and they rose about the same. If they rose more I would have upped the pressures, if less I would have lowered them.

Jeff

:rocket:

[BilboBoggles]

I believe the reason for the lower front pressure on a defender is to induce understeer and avoid over-steer, I would guess it's an important handling characteristic on a defender in an emergency situation. I'd guess that a defender is more susceptible to flipping on it's side with oversteer. So you may want to avoid keeping them at exactly the same pressure front to back.

The effect of the pressure also varies across tyre brands.

[Deelerock]

I believe the reason for the lower front pressure on a defender is to induce understeer and avoid over-steer, I would guess it's an important handling characteristic on a defender in an emergency situation. I'd guess that a defender is more susceptible to flipping on it's side with oversteer. So you may want to avoid keeping them at exactly the same pressure front to back.

The effect of the pressure also varies across tyre brands.


interesting point. makes me think about the way i did things (40 all round on road and 20 in the hills).

[AndyG]

Yes, pondering Bilbos point, be interesting to see if my MY15 110 with DSC has different tyre pressures, but I doubt it.

[vnx205]

If you use the 4 psi rule, you can get the pressures that are appropriate for the load you are carrying and the speed at which you are driving.

[AussieAub]

I run 45psi all round on the road in my 110 Puma with 235/85r16 Goodyear Wrangler MTR's.
That's to compensate for front bar, winch, front and rear heavy gauge diff guards and heavy duty bash plate, and timber rear draw system.
All the extra weight of accessories needs to be taken in mind when talking tyre pressures.
I'm still "playing" with tyre pressures that suit me best in differing off-road conditions.

I have found the best tyre pressure gauge so far to be the ARB E-Z Tyre Deflator (http://www.arb.com.au/products/general-accessories/tyre-accessories/).
Its accuracy is spot in, and can obviously be used as a tyre gauge and deflator in one unit (as it states on the packet!)

Cheers,

[rick130]

So much depends on tyre size, type and construction, let alone weight/load and distribution.......

Case in point, I used to run 33psi on road (F&R) with 255/85 BFG KM Mt's.
Running Maxxis 762 Big Horns in the same size I need 38psi F&R with the same loads.

Purely gravel, 26psi all round, all on a 130 with a decent work load in the back seat and tray.

As for the speculation re under/oversteer and tyre pressures, I highly doubt it.
Deefers tend towards understeer when pushed anyway, but roll resistance, spring rates and CofG vary wildly from vehicle to vehicle depending on setup and will influence balance far more.

[PAT303]

I believe the reason for the lower front pressure on a defender is to induce understeer and avoid over-steer, I would guess it's an important handling characteristic on a defender in an emergency situation. I'd guess that a defender is more susceptible to flipping on it's side with oversteer. So you may want to avoid keeping them at exactly the same pressure front to back.

The effect of the pressure also varies across tyre brands.

My X-Tech defender has been through the dynamic test driven by me,I ran higher front pressure lower rear and it past the test,almost all the other vehicles were the opposite and all of them rolled to the point the drivers bailed and straightened up,all the vehicles except the Ambulances were unloaded. Pat

[PAT303]

I run 45psi all round on the road in my 110 Puma with 235/85r16 Goodyear Wrangler MTR's.
That's to compensate for front bar, winch, front and rear heavy gauge diff guards and heavy duty bash plate, and timber rear draw system.
All the extra weight of accessories needs to be taken in mind when talking tyre pressures.
I'm still "playing" with tyre pressures that suit me best in differing off-road conditions.

I have found the best tyre pressure gauge so far to be the ARB E-Z Tyre Deflator (http://www.arb.com.au/products/general-accessories/tyre-accessories/).
Its accuracy is spot in, and can obviously be used as a tyre gauge and deflator in one unit (as it states on the packet!)

Cheers,

You will have no grip and the tyres will howl running those pressures,the MTR is a rubbish tyre but try lower pressures,around 36 and below. Pat

[AussieAub]

You will have no grip and the tyres will howl running those pressures,the MTR is a rubbish tyre but try lower pressures,around 36 and below. Pat

Actually having them on my vehicle, and running as I've stated, I beg to differ.

I used to run oversized 235/85r16 Hankook RT/03's on my old V8 D2 at 55 PSI all round (65-70 PSI recommended by Hankook development team after a quick phone call). I got nearly 80,000km out of those before considering replacing, and those weren't noisy either....despite people telling me they would never last and the noise would be unbearable.

There's certainly no "howling" from the current MTR tyres at any speed I've done so far. It's very smooth and quiet.
And 36 and below is a shockingly low pressure to be running at with my set up, or any "mud designated" tyre at that.....I'll leave as is thanks. :)

Cheers,

[PAT303]

How many K's have your MTR's done?,mine lasted 36,000k's running the recommended pressure.Don't know about the 70 psi on your D2,have fun with that on a corrigated track. Pat

[rick130]

36psi isn't shockingly low, try 26psi on a dirt road.
Much greater traction, much less tread chipping and wear compared to highway pressures, particularly with an MT tyre.
Our tyres have huge
volumes, compare them to a road car tyre that only ever sees around 32-36psi in a vehicle that weighs close to 2000kg and compare volumes.
A 4wd tyre is a much bigger air spring.

Most tyres don't see anywhere near their maximum load and so don't need anything like their maximum pressure, ie. the pressure on the tyre sidewall.

[FeatherWeightDriver]

Hmm - does that make me the only noob running placecard tyre pressures of 30 front 48 rear? :angel:

[FeatherWeightDriver]

Just trying to find out what tyre pressures I should be running on my 2014 Defender 110, with the standard Continental Cross Contact AT tyres.

The placard inside the drivers door says 36psi front and 48psi rears, unloaded, for road driving.


Actually - my MY14 110 running standard Continental Cross Contact AT tyres seems to have a different placecard then.

At the risk of being unpopular, are you sure your placecard says 36 for the fronts?

Mine says 30, and running 30 front 48 rears unloaded seems to give me about the same bag in the fronts and the rears...

https://www.aulro.com/afvb/images/imported/2014/08/128.jpg

[460cixy]

The placard in my ute is retarded it says 48 front and 75 rear from memory I just run 35 front 32 rear when unloaded on road gripper f 750/16

[dromader driver]

460cixy,
are you running the road grippers on the old 5.5 inch rims?

[460cixy]

Yup standard rims they fit fine good tyre too

[dromader driver]

thanks. Is yours a trayback? pressures?

[460cixy]

Yeah table top steel tray pretty sure its 35 f 32 r when empty around the 45 mark with a load of wood on. I check my placard in the morning as I wrote my pressures on it cause I forget with so many vehicles .

[460cixy]

Checked my notes that's the pressures only downfall is you have to air up a bit if you are going to put a load on

[dromader driver]

i do the same thing. adjust for load.