Advice on steering and seat vibrations please

[olddriver]

For six months I just pottered about in my car with no problems, then two months ago, during a 250 mile journey, I could feel the steering wheel AND the seat vibrating at 77, oops I mean 67.  At the time my back did not feel uncomfortable but the next day I had a serious back ache.   I had the front wheels rebalanced and the tyre shop said that the seat vibrations indicated that the rear tyres could be shaped like fifty pence pieces, although they felt the OD of the tyres and could not feel any out of round. Both the vibrations were considerably reduced, but they are still there, although they are not noticeable at lower speeds when pottering about.  Maybe some vibrations in the seat were always there, it is just that I am looking for them now.  The steering wheel vibrations seem to vary with the motorway road surface, concrete being the worst, occasionally on good tarmac there are almost no vibrations.

 

The ache is in the small of the back and comes and goes, although not noticeably worse while driving, no worse the day after a 4 hr journey, but worse the day after a 6 hr journey that I made two days later.  

 

The tyres are Goodyear Efficiency Grip, the front are about a year old and the rear are probably more than five years old.  The front shocks are two years old from Toyota and the rear are the originals.  I did think about putting a dial gauge on the OD of the rear tyres but assumed that the probe would not run smoothly on the rubber?

 

Any advice please, should I at least get the rear tyres rebalanced?  

 

I am in a quandary as I want to buy a new car, eg had a test drive in a Civic two years ago and then the bumps in the road seamed worse than in the Corolla, and I was recently driven in a Lexus IS and I was still quite conscious of the road bumps. Although I suppose the vibrations in the seat have no bearing on these "bumps"?

 

[SanaYusuf]

Sounds like age is catching up to you ha ha.

The rear tyres sound like they are past their best, I’m sure that tyres have a shelf life and as far as I know that tyres are stamped with a date of manufacture and after a certain time the rubber starts to degrade, the side walls could have weak spots for example or flat spots in the tread. 

Not a tyre expert by any means but best to start with the cheapest/obvious options first.

[olddriver]

1 hour ago, SanaYusuf said:

Sounds like age is catching up to you ha ha.

 

Yes me and the car 

No obvious date, ie no 6 digit numbers, on the tyres although E11 is written twice on the rears. The rears are actually Goodyear Duragrip made in China and the Efficiency are made in Thailand!  I would have assumed that they were UK made as I am sure that Goodyear have a factory in the UK, maybe it's "had" now.

EDIT: I now see on the internet that it is Goodyear Dunlop Tyres Ltd.

I emailed Goodyear and they replied within eight mins, but no mention of age of the tyres:-

 

"Please see below recommendations on balance/ vibration to check, some of these will already probably have been done.

We do offer an inspection service via the retailer who sold you the product. The tyres can be returned to us under warranty but we highly recommend checks have been made to be sure it is a tyre issue rather than anything else.  Below are suggestions for checks.

Simple reasons for vibration can include, balance weights falling off, wheel bolts incorrectly tightened, incorrect fitting fluid / mix, damaged rim or tyre due to potholes and uneven wear. In the case of the latter tyres in theory should wear in the manor they are presented to the road.

If none of the above apply, was a high weight needed to balance any of the new tyres? Your garage should be able to advise. Turning tyres on the rim may solve the issue, e.g. 90 degrees and on. If this does not solve the issue and there is a spare wheel, put that on instead of the tyre and wheel assembly requiring the high weight and run the vehicle up and down to see if the issue goes or reduces.

There are many reasons for vibration and unfortunately trial and error is the only way to resolve it.  If the above has not shown any results try putting the tyres presently on the rear and switch to front and see what happens.  If vibration disappears or transfers you can introduce one of the tyres back to its original position and see if the vibration moves again. If not, bring the other side to the original position again and see what happens.

In some cases a new tyre can bring out other weaknesses in the vehicle i.e. bearings, suspension, wheel rims, that had not shown themselves before. Checking the balance of the rims without tyres on is often a good idea in case there are any small chunks taken out or unnoticeable dents.

Other things to look for are tyres / rims with a high spot i.e. is there up and down movement or  is tyre going side to side.  Again, moving the tyre on the rim can sometimes solve this issue but to see if the issue is the rim or tyre chalk both in the area of movement before removing tyre from rim and then refit the tyre ensuring the 2 chalk marks do not meet.  If the tyre is moving at the rim’s chalk mark further investigation may need to be made of the rim.  If tyre still has movement where the chalk mark is on tyre then the tyre may need further investigation.

 

It is important the dealer does carry out tests before making any returns to us.  We will test tyres here on arrival and if the tyre does turn out to be within specification and something else was the cause no allowance would be advised.  Adjustments on ride issues can only be considered on tyres with less than 10% wear."

[SanaYusuf]

Since the 1980's tyres have had a date stamp added to the side walls so that you can see how old they are.

During the 80's it was a 3 digit code giving the week number and year of manufacture. So 218 would equal week 21 in 1988, when we got to the 90's to differentiate they added a triangle to the 3 digits, so 218 (followed by a triangle) would represent week 21 in 1998. It became easier to remember from the year 2000 when a four digit code was used, so 2108 would represent week 21 in 2008.

The service life of a tyre is usually measured by the amount of tread remaining; in the UK the legal limit is 1.6mm over ¾ of the tread all around the circumference. But we should also be looking at the date code as oxidisation is also a serious concern, and since tyres are made of rubber they degrade with age.

Most consumers in the UK do not know that the date code exists, a survey in 2006 showed that only 4% of drivers realised that tyres becomes more dangerous as they age. A large body of scientific evidence supports, that most tyres should be replaced six years from the date they were manufactured. This six year expiration date begins from the day the tyre was made, not from the day it was sold and fitted to a vehicle.

Tyres age dangerously because a chemical process commonly referred to as oxidisation occurs, this simply means that a tyres components are exposed to oxygen, the oxygen particles cause the flexible components of the tyre to harden and become brittle. Over time, the tyre will fall apart under normal stress, just like an old rubber band. Because this process occurs naturally, it doesn't matter if a tyre is being used, stored as a spare, or waiting on a shelf in a tyre depot, the breakdown process has started from day one.

How old is too old? This is a subject of much debate within the tyre industry and no tyre expert can tell exactly how long a tyre will last. The results of experience of many tyre manufacturing companies including Bridgestone, warrant their tyres for 5 years from date of manufacture. Based on these understandings many vehicle manufacturers are now advising their customers to replace their tyres after 6 years, regardless of tread depth remaining.

[SanaYusuf]

https://www.hometyre.co.uk/mobile-tyre-fitting/mobile-tyre-fitting-sussex/blog/do-tyres-have-a-shelf-life/

*Info was taken from this site.

[oldcodger]

Without doubt  have the rear wheels balanced.

 

Really cannot understand any garage not saying the rears should be balance as well given your problem.

Checking for roundness,....hmm, more usual to check for bulges on the sidewall which can affect the balance and fail the mot; also checking for even tread wear to suggest the alignments are correct.

Also a tyre 5 years old will likely be slightly out of balance due to normal wear.

Never rely on just one place balancing your tyres, its always down to the machine and operator as to how good the balance is and also what selection of weights they have.

You can prove things yourself, to a degree,  by swapping the fronts to the back and seeing if you get more or less steering judder at 60ish.

Even with the fronts in perfect balance, the rears being out can cause both seat and steering vibration.

If original, your rear shocks could be totally worn out and cause a lot of vibration, though again your garage should have bounced tested them, as can you.

 

 

[olddriver]

1 hour ago, oldcodger said:

Without doubt  have the rear wheels balanced.

Checking for roundness,….hmm, more usual to check for bulges on the sidewall which can affect the balance and fail the mot; also checking for even tread wear to suggest the alignments are correct.  Had the front alignment checked 

Never rely on just one place balancing your tyres, its always down to the machine and operator as to how good the balance is and also what selection of weights they have.

You can prove things yourself, to a degree,  by swapping the fronts to the back and seeing if you get more or less steering judder at 60ish.

Even with the fronts in perfect balance, the rears being out can cause both seat and steering vibration.

If original, your rear shocks could be totally worn out and cause a lot of vibration, though again your garage should have bounced tested them, as can you.

Thanks, yes I will get them balanced

"Roundness", I had the car MOT the day before the first time I noted the problem, so they should have noted any bulges on the tyres.

"Balancing", yes, previously I've had to take the car back to balance a wheel after fitting a new tyre, not the same shop as where these were fitted.  Had the front alignment reset in July on a Hawk-Eye machine.

"Swapping back to front", not keen on doing that as I have had an older, Goodyear I think, rear tyre shred on the Motorway at 80!  The tread would have been legal, the current rears have about 1mm above the 1.6mm bump

"Rears out of balance", after rebalancing the rears, if the problem is still there then maybe I will buy new rear tyres.

"Rear shocks" just checked and they bounced one and a half times.

SanaYusuf

Thanks, but I cannot see any numbers shorter than seven digits or anything representing a date.

[olddriver]

I've checked my diary and it appears that six weeks before the vibration problem became apparent, I was again 250 miles away from home in June and had the front callipers changed and the front wheel alignment reset on a Hawk-Eye machine:-

 

In my diary, I did not comment on that "250 mile journey back home in June" so I assume that there was nothing too untoward, but I did have a back ache two days later so maybe the seat vibrated but not enough for me to be conscious of it.  It seems to me that it is unlikely to be the callipers causing the vibrations and therefore I would have thought that either there was a gradual decay in the tyres and or the loss of wheel weight/s during or after the "250 mile journey back home in June". Note, the worst vibration journey occurred in August after the MOT.

[Mike169]

Hi 'Olddriver', just a thought, what's your spare wheel/tyre like if you have one? Just putting it on one side of the rear and then messing about put it on the other side and of course road tests inbetween, that should help determine if you have a tyre gone out of shape. Incidentally the shelf like of a new tyre is 7 years I believe, after that they shouldn't be sold so I had a car once I had just bought and the tyres were 9 years old so I had a new set fitted and the inside of the old tyres was perishing, tyres don't last forever regardless of how much tread is left on the tyre, i.e. the 1.6mm or the wear bars coming up. Mike. 

[olddriver]

2 hours ago, Mike169 said:

Hi 'Olddriver', just a thought, what's your spare wheel/tyre like if you have one?

Thanks Mike, unfortunately my spare is just that, I was driven off the road and had to drive up a curb to avoid an accident and consequently damaged the rim, although I did manage to hammer it back into shape.  Additionally, the tyre is probably 19 years old as it is a Michelin that I believe was on the car when I bought it new, I hate Michelin because of the useless grip, so it is unlikely that I actually had it fitted.  After the Michelins wore out, I fitted Goodyear or Dunlop and was able to take a particular bend that I knew well at 50 instead of 40, and the Michelins were useless in the wet.

I doubt that they are older than 7 years, unless they were in storage for a long time before I bought them.  I haven't recorded when I bought them but in the past I recon that I got 20,000 to 30,000 miles out of Dunlops or Goodyears, so I could have had them on the car for 5 years. When buying new tyres, I usually put the two best tyres on the back and buy new ones for the front.

[KenMavor]

20 hours ago, olddriver said:

Thanks Mike, unfortunately my spare is just that, I was driven off the road and had to drive up a curb to avoid an accident and consequently damaged the rim, although I did manage to hammer it back into shape.  

When did this happen..?  Was all the rest of the running gear checked out to be Ok?  You could have easily bent a track rod or similar and as the tread of the tyres reduce any issue will become more pronounced.

I worry that your rears have only 1mm above the 1.6mm bump.  Whilst maybe road legal they will provide a lack of grip, especially, in the wet, going round a roundabout for instance.

Is there any noticeable uneven wear anywhere?  On the shoulders?  in the centre?  Are tyres at the correct pressure?

All worth checking.

If you are feeling vibrations through the seat then something is not quite right.  Suggest the seat should be Ok.....can u rock it backwards and forwards or side to side at all when car is stationary?

 

[olddriver]

1 hour ago, KenMavor said:

When did this happen..? 

Is there any noticeable uneven wear anywhere?  On the shoulders?  in the centre?  Are tyres at the correct pressure?

Thanks.

That was about 10 years ago and no problems until after I had the Hawk-Eye work done, I wonder if they dislodged the wheel balance weights, getting the rears checked today.  EDIT Probably driving 250 miles tomorrow, so will see then if that sorts it.

No noticeable uneven wear.

 

[olddriver]

On 23 October 2017 at 5:26 PM, oldcodger said:

Without doubt  have the rear wheels balanced.

Also a tyre 5 years old will likely be slightly out of balance due to normal wear.

 

You're right on the money oldcodger.

The tyre shop said that they refitted similar weights to the rear wheels but in different positions. The steering wheel is now steady at motorway speeds.  I am not completely sure about the seat, because in the interim, I bought a 11 deg Coccyx wedge cushion:-

http://www.kozeekomforts.co.uk/department/comfort-and-heat-therapy/coccyx-wedge-cushion.php

I drove about 200 miles with that on the seat but was too busy concentrating on driving to assess the seat, it was only then that the traffic was light enough for me to be able to put my hand down between my legs and feel the seat squab.  The seat squab was vibration free but the back appeared to move up and down considerably with the unevenness in the road surface.  In desperation, at about 20 miles from home, I pulled out the cushion from under me, and a huge relief came over me and I felt comfortable, it was unbelievable the difference that it made without the wedge cushion.  Consequently, the vibration problems appear to have been resolved, with thanks to all.

[mickburkesnr]

Was about to say I had the same problems as you described with my E11 when I bough it. You get to motorway speeds and the steering vibrates and, to me, the whole car would vibrate. Turned out none of the tyres were balanced. The previous owner just threw whatever was cheap on the car as it only did short trips. Wheel balancing resolved the issue, as it did with you :)