Any help would be much appreciated - I am looking to change all four tyres on my van this month {Elddis Crusader super sirocco 2008 - tyres 175/65 tr14 90 load}.The question being do I need to go for the XL/Reinforced tyres or standard?...Thankyou for any help.
XL Reinforced tyres?
- Thread starter adam_374374842
- Start date
Doesn’t the Owners Handbook state the tyre spec? Given equality of size, speed rating and load rating I would opt for reinforced XL as long as the above parameters are met, or exceeded.
You won't need XL tyres on a TA - standard tyres are fine. Load index is the key thing to take note of. If you take the MPTLM of the van and add at least 10%, you'll need to fit tyres that are each rated to support at least a quarter of that weight. There are plenty of on line tables of weight vs load index.
The purpose of the 10% is to give a safety margin in case of accidental overloading. You probably won't find a load index that gives that exactly, so 10-15% would be ok.
XL tyres by design have much stiffer sidewalls, and these will impart a harder ride to your van. It gets forgotten that the flex in tyre sidewalls provides some element of the vans overall suspension. I don't see it being a good idea to shake the van to bits any faster than they do...
The purpose of the 10% is to give a safety margin in case of accidental overloading. You probably won't find a load index that gives that exactly, so 10-15% would be ok.
XL tyres by design have much stiffer sidewalls, and these will impart a harder ride to your van. It gets forgotten that the flex in tyre sidewalls provides some element of the vans overall suspension. I don't see it being a good idea to shake the van to bits any faster than they do...
adam_374374842 said:
The tyre size from my records as i had the same van and year were 175/65 r14 86 load
So 86 is 530Kg and 90 is 600 kg - the latter is rather high.
My own TA van has a MTPLM of 1900kg and the load index is 87 (545Kg) so rated up to a total 2180Kg
My own TA van has a MTPLM of 1900kg and the load index is 87 (545Kg) so rated up to a total 2180Kg
Thankyou for the replies - posted the question purely for the reason would it be worthwhile for a few extra pounds to move over to XL/Reinforced tyres over my standard ones fitted at the moment {as Michael stated} regarding safety - are there any big advantages or any disadvantages - although explained by Chris {Thankyou very informative} I will stay put with what I have.Thanks.
I could not understand why you should want to exceed the specification of the tyre the manufacturer had specified.
Going for a higher load rating would of course cover any overload situation, but as Chrisn7 pointed out the normal selection process already covers that, so it would be pointless exercise. Unless there was a significant cost saving.
Chrisn7 has also pointed out that high load rating does man the tyre will have stiffer side walls, and that will mean they will transmit more of the road surface vibrations to the caravan, The damage they may cause will vastly over shadow any cost saving on the tyres.
I am certain there will be others who will disagree with me, but the caravan manufacturers will have done their sums and will have chosen a tyre specification that will match the weight of their caravans and are compliant with the law, so why spend time and effort in trying to re do on an armature basis what they do professionally.
Going for a higher load rating would of course cover any overload situation, but as Chrisn7 pointed out the normal selection process already covers that, so it would be pointless exercise. Unless there was a significant cost saving.
Chrisn7 has also pointed out that high load rating does man the tyre will have stiffer side walls, and that will mean they will transmit more of the road surface vibrations to the caravan, The damage they may cause will vastly over shadow any cost saving on the tyres.
I am certain there will be others who will disagree with me, but the caravan manufacturers will have done their sums and will have chosen a tyre specification that will match the weight of their caravans and are compliant with the law, so why spend time and effort in trying to re do on an armature basis what they do professionally.
ProfJohnL, I totally agree with you! Absolutely no reason whatsoever to change tyre specification.
ProfJohnL said:
Makes perfect sense. I always replace tyres with the same spec, on the basis that the manufacturers must have done their homework and I see no reason why I can do better.
.......bear in mind that it was not that long ago that most caravans had 13 inch rims as opposed to the almost universal fitting of 14 inch rims today.
There are still quite a few of these single axle caravans around and their handbooks and manufacturers specification will tell you to fit reinforced tyres and inflate to a pressure of 40-42 psi.
You will find it impossible to find this type of tyre to fit 13 inch rims today.
You will have to fit a commercial van tyre with a C rating and they will need to be inflated to a higher pressure.
There are still quite a few of these single axle caravans around and their handbooks and manufacturers specification will tell you to fit reinforced tyres and inflate to a pressure of 40-42 psi.
You will find it impossible to find this type of tyre to fit 13 inch rims today.
You will have to fit a commercial van tyre with a C rating and they will need to be inflated to a higher pressure.
MichaelE said:
Oddly I'm not of the same mind on this subject as John and others on this subject, preferring to take the word of the tyre manufactures themselves. In general as been more or less stated, tyres when fitted to caravans should not be expected to carry their full design load on a constant basis, so a minimum 10% margin should be allowed due to the extraordinary condition they endure.
Given that, I was intrigued by the OP's tyre size as that load index is not listed in the tyre industry's common caravan tyres load/pressure chart, but I found one example by Nankane! 175/65R14 T90, listed on Blackcircle Tyres as a 'Van' tyre so already above the spec of either car or XL car tyres, so possibly an '8ply' Commercial tyre but with the C missing?? Certainly appears to fit in the list I do have of similar tyres
As for the 175/65R14 86 (XL) Reinforced tyre, 4 of them are recommended up to 1882kg @ 37psi, (38psi taking them somewhat outside suitable at 1942kg)
Im not sure what you are trying to say? 86 rated tyres have a max load of 530kgs so x 4 equals 2120 kgs?gary said:
Elddis also recommend 40psi on these tyres.
MichaelE said:
Well this link should answer the questions, including my doubts as to the exact type of tyre the OP has, I didn't think to look at my old, and online, chart originally from the mid 90's! but it's listed at the bottom!. :huh:
http://arcsystems.biz/Pictures/tp.jpg www.arcsystems.biz/Pictures/tp.jpg
One though glaring problem with any other choice is this particular tyres diameter, that it's not compatible with otherwise suitable choices, unless increasing diameter somewhat would be beneficial to ride height?
To my knowledge there are two companies that make trailer specific tyres which are designed for freewheeling applications. The sidewalls have the marking “trailer use only” They are Kenda and GTRadial. I have used both types on past caravans although with my current caravan I stick with the OEM Hankook commercial C- rated tyre. One thing I did notice with both Kenda and GTRadial is that some tyres have two Load Indexes embossed on the sidewall. One is for twin axle use, the other for single axle use.
http://www.gtradial.co.uk/gtradial/uk/newsdetail.asp?newsid=1241
http://www.gtradial.co.uk/gtradial/uk/newsdetail.asp?newsid=1241
Clive, regards two load index number's on C rated tyres, the lower number is not for twin axle use, it's twin wheel, (where two wheels are used side by side on both side of a single axle)
Gafferbill said:
chrisn7 said:
.......I am aware that the OP has a twin axle caravan on 14 inch rims.
You gave the OP excellent advice but others asked why he was questioning the tyre specifications laid down by the manufacturer and written in the handbook.
My post was attempting to point out that for older caravans, handbooks and manufacturer recommendations can become outdated.
There is a particular safety issue regarding inflation pressures for 13 inch caravan tyres.
Modern tyres that are available in this size have a higher inflation pressure than tyres that were originally supplied.
A non technical owner who follows his handbook could be towing with under inflated tyres.........my post was for general interest and not specific to the OP.
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