Tyres

[shaunm41]

Can anyone enlighten me as to the need for different sized tyres front and rear? I need some all terrains and I'm really struggling. It's a 2004 (facelift) 3.0d sport with 19' rims. Currently 285/45 rear and 245/50 front (I think) but I'm hoping to fit general grabber at 255/50/19 on al 4 corners. Any potential issues this might cause?

Thanks

Shaun

[X5Sport]

The difference is because the 19" rims are 9.5" wide on the front and 10.5" on the rear hence needing a different profile in order to maintain the correct rolling radius.  285 is the tread width and the 50 is the sidewall height as a percentage of that width.  So a 255/50 will have a different rolling radius to a 245/50 as an example.

You will probably have issues getting the tyre to sit correctly on the wider rim.  Make sure whatever you fit has the same rolling radius all round or you will affect the speedo accuracy as well as winding up and breaking the transmission.  You must also maintain the Loading Index or go higher, but never below.  The index is the last set of characters in the size such as 315/35 R20 109Y.

Non-Sport models came with non-staggered (same width) 17" wheels the same as the spare.

R

[shaunm41]

Thanks for the informative reply.

So in theory the general grabbers I mentioned will be no good?

Just out if interest, is the spare generally the same as a front? As my n/s front wheel has been badly curbed so was going to swap them over if there the same

[Greydog]

Remember All Terrain tyres do have restricted performance when fitted to a car like the X5 they are noisy too.
I fitted Grabber UHP tyres just over a year back, they have been on the car winter and summer and I am really pleased with them. They are not All Terrain but last years mud and snow didn't phase them or the X I even pulled a couple of Disco's out of really deep snotty ruts while out shooting ((they were on road tyres).
On the motorway they aren't or don't seem to me to be any noisier than the tyres that were on the car when I brought it, wear rate seems to be good they will certainly do another messy winter. I would buy another set.

[shaunm41]

I was looking at the grabber UHP's and so far they looking like the best option. Although I don't intend in 'off roading' as such, u do need some off road capability on the estate we shoot and fly hawks on. Driving up muddy fields, stuff like that. Also will be towing a bit too. But I'm thinking we may be in for a bad winter and I don't want to be limited to what I can do so need some suitable tyres.

Not sure how well an X5 will get along with the tasks I require of it but I have a quad for the really muddy / crappy stuff on the estate if I can't use the X5

[ChrisABP]

You could fit the same size tyres front and rear (known as a square set-up) but you would need to change the wheels to a set with the same size on both axles. Most Winter set-ups use a square set-up so maybe find a set of Winter wheels that you could use the all terrain tyres on - this way you may be able to go down to 18" making the tyre choice more widely available and cheaper.

Chris

[shaunm41]

What about if I found a set of 19' fronts and put them on the rear? Then fitted the grabber at2 all round? Would that work?

[Nat]

Hi,

Well you could but it would look shit unless you used a big spacer.

Your fronts should be 255/55/19 anyway

You may squeeze a 265 on the rear, defo get a 275 on there.

Have a look here,

http://www.camskill.co.uk/m57b0s0p0/SUV ... _-_19_inch

Where u going that u need all terrain ?

[X5Sport]

The key bit is to stay on one of the manufacturers quoted tyre sizes for the car - as shown in the tyre pressure label on the driver's side 'B'-pillar.

You must maintain the correct rolling diameter or as I said, your speedo will be out.  As long as you fit the right profile then all will be fine.  There are sites where you can check the profiles against OEM data to find correct sizes that will match the rolling dia - the 17" size is 235/65R17 as an example which is the same as the 255/50R19 which is the correct front size and not as above in NAT's post.

R

[Greydog]

Hi Shaun 41
Sounds like we use our X5's for similar stuff, shortly after buying it I changed the tyres to staggered 19" Grabber UHP tyres. Whe I brought the X it was to pull a horse box after we sold the Horse Lorry. I also shoot all over the country starting in August through to the end of the season, plenty of friends
told me the X wouldn't cope "off road". Well that depends on your definition of "off road". Last year we visited plenty of horse shows and events around the South of the country, snotty gateways and wet soft fields pulling 2 horses in the box absolutely no problem. Then the season started and as I said 2 Disco's who got stuck in deep muddy ruts that I had driven through were pulled out by me. The snow arrived and once again the X on Grabbers just went wherever I needed to get to with no major drama's. This year has been a repeat of last year for use.

My tyres are 255 x 50 x 19 front 285 x 45 x 19 rears as the original tyres.

[shaunm41]

Well if yours coped with all that I rekon I should be ok. I've just ordered a set of grabber UHPs in the original sizes so that should be ok. What pattern has your grabbers got? The ones I had ordered had a v type pattern which looked good but they emailed and said the pattern of the UHPs has now changed to the same pattern as the grabber GT

[AW8]

Not aware of a pattern change

UHP was being phased out - no longer listed on General website for europe. click here

GT marketed as 100% on road 0% off road...........whilst this may seem ideal for many I suspect some may avoid tyres if they perceive them as totally unsuitable for off road use..........The last thing the owner of a luxury 4x4 wants is to find themselves bogged down after parking in a wet field (maybe after a day at the races, golf or country show etc).

Fwiw UHP should look like this .... click here

I am just wondering if supplier is telling you of a UHP pattern change in hope you don't take issue with GT's.

Maybe ask if the tyres you have ordered have "General Grabber UHP" written on the side wall.


No head office in UK for General Tyres albeit some UK tyre suppliers may have more info. Try asking Southam Tyres, Micheldever Tyres, Black Circles, AJS Tyres......be careful how you word your enquiry as I suspect some may be reluctant to assist if you have bought elsewhere 
 
I wish you Good Luck

[shaunm41]

I spoke with them and they said they are the GT tyres and they have replaced the uhp as they are a better tyre. They said the 80/20 or 100/0 on/off road listings are a load of rubbish and both gt and uhp are the same. Both on road only tyres. Are they taking the piss?

[AW8]

In answer to your question they are in so much as...........

1. You specifically asked for HP not GT.
2. They wrongly told you the UHP pattern had changed - it has not.
3. They told you the two different tyres are the same they are not

I have seen favourable reviews on the UHP but nothing of any substance typed re the GT.

Your supplier can say all they want but the bottom line is the GT has a street tread pattern and is marketed by the people who make them as 0% off road

I strongly suggest you call Southam Tyres  on 01926 813510 as they are one of the main importers in the UK. I have always found Micheldever tyres helpful. Andy from AJS tyres have been plugging the GT's when posting on other sites albeit not seen any detailed reviews.......also mindful that anyone you speak to also has business interest in selling tyres.

In an ideal world General AT2 and/or Toyo ST2 would be available in UK in staggered 19 inch sizes......The ST2 has better ability with light snow due to design & snipes 

Oh and I wouldnt buy UHP as if you get a blow out you wont be able to source another easily if at all with any haste............That means after replacement you will be driving with differing tread patterns which is far from ideal in that scenario.

[AW8]

Hankok Ventus RH06 maybe worth a look if you want all season and less street terrain tread pattern. Never used them so look for reviews and forum discussions on other sites..........Use the discussion search option in google.

Do make sure you get tyres with correct load index

http://www.1010tires.com/Tires/Reviews/ ... us+ST+RH06

Also the original Toyo Proxes ST (not the sport ones) have V tread pattern. Many on hear swear by them http://www.toyo.co.uk/tire/pattern/proxes-st

If you want more off road dedicated rubber I think you will need to swap to 17 or 18 inch wheels.

Do also bear in mind the real environments and climates you will be using car in.

More off road based tyres can have trade offs on the road.........such as handling, roadholding and grip in dry.

Oh and a big diesel spill on a sharp bend in wet is likely to cause issues for most tyres