Kia Owners Club Forum banner

61 - 80 of 80 Posts

·
Registered
Joined
·
1,829 Posts
Purely with reference to the expression, ‘Transmission wind-up’, I attach two links which may provide a greater understanding for those who may not understand fully the potential risk of expensive failure if incorrect usage of 4WD is practised.

The first is a very short animated guide while the second is a more detailed explanation.

I hope it helps.


 

·
Registered
Joined
·
114 Posts
Yes almost ALL car manuals suggest rotating tyres. It's not specific to the Sportage - that's just plain old common sense advice - a bit like "take car in icy conditions - your car may not behave the same" or "when it's dark, turn your lights on".

I'm still waiting for this specific Kia advice that says you cannot run the car with more than 2mm tread difference between each axle....
 

·
Registered
Joined
·
665 Posts
It makes no sense to me for a car manufacturer to run tolerances that tight on a mass production car driven by all sorts of people.
Someone running their tyres soft could possibly account for more difference in rolling radius than a car with tread differences.
 

·
Registered
Joined
·
114 Posts
Exactly - a few PSI out and you'd have a much bigger issue than a few mm tread difference.
So on that basis I am sure that the Kia engineers have programmed the TPMS to prevent the car from being driven if a tyre is low on pressure - as surely to so would wreck the AWD system???

BTW, I'm still waiting for someone to point me to the section in the manual where the 2mm tread difference is stipulated....
 

·
Registered
Joined
·
260 Posts
Where I live we don't really have any straight roads anyway, same applies in many places where 4wd vehicles are popular. This will equate to more than 2mm tread depth.

2mm tread = about 6mm circumference. Which is 1.6 revolutions/mile difference on a straight road.

Anyone can mark their 4 tyres with a crayon @ 12 o'clock, drive half a mile, and compare the difference. It will usually equate to more than tread depth variations
 

·
Registered
Joined
·
3,847 Posts
I have been reading my manual and I cannot see any particular warnings about tyre tread depth. There is a recommendation to rotate the wheels every 7,500 miles to equalise tread wear but it does not state why. In the tone of the rest of the manual I would expect some stronger warnings about this if it were all that important so I am coming round to the idea that front/back wear imbalance is not a certain way to destroy the transmission. IIRC the 2 - 3 mm tread depth difference is something that has crept in on here variously via KCS and relayed from some dealers - I don't think it's stated anywhere in my manual.

We have had users on here reporting various banging and thumping which have been traced to significant tread wear or inflation pressure imbalance so that can falsely trigger AWD but with so much sensor technology embedded in the control systems it would be remiss of KIA to allow the car to destroy it's transmission without at least some warning or automatic AWD disable.
 

·
Registered
Joined
·
3,847 Posts
Where I live we don't really have any straight roads anyway, same applies in many places where 4wd vehicles are popular. This will equate to more than 2mm tread depth.

2mm tread = about 6mm circumference. Which is 1.6 revolutions/mile difference on a straight road.

Anyone can mark their 4 tyres with a crayon @ 12 o'clock, drive half a mile, and compare the difference. It will usually equate to more than tread depth variations
On any other than a perfectly straight road all four wheels will be rotating at different speeds so of course your crayon lines will not line up. It would not be sensible for KIA to engineer the AWD system to trigger at the slightest imbalance between front/back wheels so there will be a degree of tolerance built in to the AWD activation process. In normal cornering the difference between front and back wheel speed is very small (fronts have to travel a slightly greater distance than the rears when cornering), but tread wear or inflation pressure imbalance will add to the apparent difference where the fronts have a smaller rolling radius than the rears or reduce the imbalance where the rears are smaller than the fronts.

Side to side differences are greater but that is why we have differentials and this will not be something the AWD is sensitive to.
 

·
Registered
Joined
·
665 Posts
I have been reading my manual and I cannot see any particular warnings about tyre tread depth. There is a recommendation to rotate the wheels every 7,500 miles to equalise tread wear but it does not state why.
Does it specify that for 4WD models only?
Or is the manual specific to the 4WD model?
My gut feeling is the 2WD manual will say the same thing, just a generic recommendation that very few actually pay heed to.
 

·
Registered
Joined
·
3,847 Posts
I think the manual covers all Sportages. There is a section marked "All Wheel Drive (if equipped)" so I think it covers all transmission types.
 

·
Registered
Joined
·
416 Posts
Exactly - a few PSI out and you'd have a much bigger issue than a few mm tread difference.
So on that basis I am sure that the Kia engineers have programmed the TPMS to prevent the car from being driven if a tyre is low on pressure - as surely to so would wreck the AWD system???

BTW, I'm still waiting for someone to point me to the section in the manual where the 2mm tread difference is stipulated....
As stated before, it’s not listed in the manual as far as I’ve been able to tell. However, when I contacted Kia directly they did confirm that there was a 2mm tolerance
 

·
Registered
Joined
·
3,847 Posts
As stated before, it’s not listed in the manual as far as I’ve been able to tell. However, when I contacted Kia directly they did confirm that there was a 2mm tolerance
So go back to them and ask how an ordinary user can know this if it is not made clear in the user manual. If their car has a particular requirement in this area then they really should take care to point it out.
 

·
Registered
Joined
·
114 Posts
As stated before, it’s not listed in the manual as far as I’ve been able to tell. However, when I contacted Kia directly they did confirm that there was a 2mm tolerance
Kia UK HQ or a Kia dealer?
If the latter I'd not listen to a word of it - they spout all sorts of guff.
If the former then I'd be asking why these cars don't come with strong warnings as to the dangers of not checking your tyre treads & tyre pressures on a pretty much daily basis.

And if there really was a 2mm tolerance then sorry, but the internet would be full of stories of Sportage's with failed AWD systems and BBC Watchdog would be on the case by now.
 

·
Registered
Joined
·
416 Posts
Kia UK HQ or a Kia dealer?
If the latter I'd not listen to a word of it - they spout all sorts of guff.
If the former then I'd be asking why these cars don't come with strong warnings as to the dangers of not checking your tyre treads & tyre pressures on a pretty much daily basis.

And if there really was a 2mm tolerance then sorry, but the internet would be full of stories of Sportage's with failed AWD systems and BBC Watchdog would be on the case by now.
It was kia UK customer services via email. When I asked about the potential issue caused to the AWD system as if heard various stories of potential damage caused due to tyre treads etc, I asked if it was correct as I couldn’t see anything in manual regarding it.
They pointed me to the page in manual that states about rotating tyres. This is what they said to me:
“All the tyre wear and tyre rotation information for your Kia can be found in your owner’s manual, Section 8 (maintenance) page 64 to 75.

Ultimately if the tyres are unevenly worn this could cause problems with the drive train of the vehicle due to the tyres traveling different distances. Its important to note that when rotating the tyres on your Kia you should include the spare in the rotation as can be seen on the diagram in section 8 page 67.

Please be aware we advise no more than a 2mm difference in tyre depth, left to right and front to rear.“

I did then ask what happens if you get a puncture, do you have to then replace all 4 wheels instead of just the one. They stated that they’d recommend that tyres on same axle was of same tread wear and depth.

I then said so what about the rear tyres, is it just the tyres on same axle then that need to be within 2mm tolerance and that’s when I was told that it’s better to contact dealership as they had technicians that would be better placed to answer this query.
I did already do this though and was told that I didn’t really need to rotate tyres and wasn’t something that was done frequently by customers so not really sure still what’s right or wrong. Seem to be getting conflicting info.
Maybe if others tried contacting Kia as well we might get a better answer?
 

·
Registered
Joined
·
3,847 Posts
daveyboy, did you point out to them that the words they referenced give only a "recommendation" rather than stating that it is "important", "necessary" or "vital"?
 

·
Registered
Joined
·
665 Posts
daveyboy, did you point out to them that the words they referenced give only a "recommendation" rather than stating that it is "important", "necessary" or "vital"?
Pretty key wording, isn't it.
Like the difference between 'should not' and 'must not' in the highway code.
 

·
Registered
Joined
·
416 Posts
daveyboy, did you point out to them that the words they referenced give only a "recommendation" rather than stating that it is "important", "necessary" or "vital"?
To be honest, I left it after that as they advised to speak to dealership instead. It’s just strange as to me something that’s made to sound so important isn’t highlighted at all in any manual.
most people would not be part of online forums so these people I assume could be running their car incorrectly and will only know about it when it actually breaks something.
I’m still none the wiser though regarding the tread levels. Is it as important for front to rear tread levels roughly the same? Or is it more important for both front wheels and both rear wheels to have similar tread wear etc.

is there anyway of knowing when AWD kicks in? So if there was something wrong then you could potentially be aware of issue?
 

·
Registered
Joined
·
665 Posts
is there anyway of knowing when AWD kicks in?
Like a warning light?
Doubt it, we've had a Hyundai and a Honda both with auto 4x4 systems and neither told you when it was kicking in.
If you want to make sure it does work, take it somewhere slippy and floor it.
I'm not being flippant, it's honestly the only way you'll know.
Front wheels spin > back wheels kick in > working.
 

·
Registered
Joined
·
3,847 Posts
To be honest, I left it after that as they advised to speak to dealership instead. It’s just strange as to me something that’s made to sound so important isn’t highlighted at all in any manual.
most people would not be part of online forums so these people I assume could be running their car incorrectly and will only know about it when it actually breaks something.
I’m still none the wiser though regarding the tread levels. Is it as important for front to rear tread levels roughly the same? Or is it more important for both front wheels and both rear wheels to have similar tread wear etc.

is there anyway of knowing when AWD kicks in? So if there was something wrong then you could potentially be aware of issue?
You should not encounter significant tread wear differences side to side - if you do then there is something wrong with the tyre pressures, tracking or suspension. It is usual to get a little more wear on the nearside front because roundabouts mean that we tend to spend more time turning right than left. Front/back is where AWD starts to come in and only if the fronts are much more worn that the rears. Fronts will wear faster than rears anyway so this is why rotating them will put the more worn tyre on the rear and this will not trigger AWD falsely.

I have induced the "torque vectoring" aspect of AWD on the road. Cornering on a road I know well and deliberately chose to go in to a bend a little faster (I believe in exploring these thing gently) than I had previously.. As the car starts to take the corner you start to get a little understeer (no squealing) and the front starts to wash out towards the outside of the bend. I was just at the point when I was going to tighten the steering to hold the line and I felt a very slight lurch and the car went round the rest of the bend like it was on rails. I am sure that this was torque vectoring (it applies partial drive to the rears) rather than ESP. [I have induced ESP intervention deliberately in an icy car park and for me it needed a significant difference between steering angle and vehicle yaw rate before it steps in - you do get flickering lights on the dash when this happens too].

If you have front tyre wear to the point that it is inducing AWD on a sound surface you will notice the car tightening up (almost like braking) and more particularly when it disengages there will be a noticeable thump and possibly lurch. I don't think there is a light for auto AWD engagement but I might be wrong on that. If it is particularly bad then when cornering at low speed you will again feel the car tighten up and possibly even slow down a bit. Other symptoms include "skipping" when cornering and assorted thumps and bangs from the chassis. There are posts on here describing these symptoms so have a search and a read. You will know that your car is not responding like it normally does,.
 

·
Registered
Joined
·
416 Posts
You should not encounter significant tread wear differences side to side - if you do then there is something wrong with the tyre pressures, tracking or suspension. It is usual to get a little more wear on the nearside front because roundabouts mean that we tend to spend more time turning right than left. Front/back is where AWD starts to come in and only if the fronts are much more worn that the rears. Fronts will wear faster than rears anyway so this is why rotating them will put the more worn tyre on the rear and this will not trigger AWD falsely.

I have induced the "torque vectoring" aspect of AWD on the road. Cornering on a road I know well and deliberately chose to go in to a bend a little faster (I believe in exploring these thing gently) than I had previously.. As the car starts to take the corner you start to get a little understeer (no squealing) and the front starts to wash out towards the outside of the bend. I was just at the point when I was going to tighten the steering to hold the line and I felt a very slight lurch and the car went round the rest of the bend like it was on rails. I am sure that this was torque vectoring (it applies partial drive to the rears) rather than ESP. [I have induced ESP intervention deliberately in an icy car park and for me it needed a significant difference between steering angle and vehicle yaw rate before it steps in - you do get flickering lights on the dash when this happens too].

If you have front tyre wear to the point that it is inducing AWD on a sound surface you will notice the car tightening up (almost like braking) and more particularly when it disengages there will be a noticeable thump and possibly lurch. I don't think there is a light for auto AWD engagement but I might be wrong on that. If it is particularly bad then when cornering at low speed you will again feel the car tighten up and possibly even slow down a bit. Other symptoms include "skipping" when cornering and assorted thumps and bangs from the chassis. There are posts on here describing these symptoms so have a search and a read. You will know that your car is not responding like it normally does,.
Yes you are right, I’ve never had any noticeable wear differences between two sides, only ever front to back. That’s why I’m confused that the advice was that if one tyre got punctured then as long as both tyres on same axle are similar tread then won’t be a problem. But from reading on here and other sites etc it would seem that you should still change all 4 so I’m a little frustrated that I’ve been told various things that seem to contradict each other (Kia I mean). As I’ve said before kia email seemed to say yes to 2mm tread wear but then said if you get a puncture just make sure the tread on same axle is all same (this is to me not correct and contradicts what they said previously) and secondly when I rang dealership I was advised that the rotating of tyres is not normally a necessity and isn’t really asked for as usually by time fronts need replacing the rears would as well.
So it seems to me that there is no clear guidance from the actual manufacturer which is really frustrating.

I think we said before though that it’s best to just keep an eye on treadwear between front and rears and rotate if necessary. 2mm difference seems to be quite small though.

has anyone had tyres running with a bigger margin between front and rears and did they encounter issues?
 
61 - 80 of 80 Posts
Top