Constant light vibration/sudden hesitation while driving

[RahExplorer]

Hi all - new member with a first post here. I have a 2008 V6 Eddie Bauer with 96,000 kilometers on it, bought used in Oct last year with about 81,000 KM on it at the time. About 2 months ago, when going for an oil change, I noticed the front driver shock was leaking - nothing serious, but certainly noticeable. Having said that, the car drove fine, so I left it thinking I would get around to having it fixed at some point. About a month ago, I noticed the car had developed a light vibration...difficult to explain - you can feel it is constantly there, with more of a "rougher ride" compared to how it was before. Every now and again it makes the car suddenly feel as if it is hesitating while driving, almost like the engine cut out for a second then returned, but it is not an engine issue, all appears to be fine on that front. You can feel the vibration mainly above 60Km/hr when cruising. Again, nothing crazy, but that sudden hesitiation every now and again is odd. Anyway, thinking it was my failing shock, I got it swapped out with a new one...but it made no difference to the vibration issue. A little gobsmacked, I took it to my Ford dealer. They took a good look at it over a day and concluded it is the tires. They are some 3 years old, with small hairline cracks around the side, and they are saying when this happens they've degraded enough to start causing these types of issues. I live in Dubai, and the conditions out here can be pretty brutal from a heat perspective - some 140 to up to 150 Deg F in the summer, but otherwise streets are relatively smooth. Anyway, they are saying the condition of these has made them warp or otherwise knock out of shape and are recommending I don't even waste time or money re-balancing them or anything as they say they are bad enough to recommend changing outright.

On looking at the tires, I cannot see any obvious signs of odd wear, cupping, etc. and although they have these hairline cracks, they otherwise have a good amount of wear left and, at least from novice viewpoint, appear to be fine. So Im really not sure whether I would want to be forking out for a brand new set of tires at this point, without honestly knowing if that is going to fix the vibration issue in any case....

All being said, I wondered if any of you have across something like this before, or can take a guess at what could be causing this? The other theory was engine mounts failing, but the vibration does not happen at all at idle and the mounts appear to be ok. Thanks in advance for any thoughts.

 

[Themightyquinn]

is there a humming accompanying the vibration? do you feel it in the steering wheel? rotate the tires and see if you still get front end vibration

 

[RahExplorer]

Hi - no humming, just a constant bumpy ride, with occasional sudden hesitation. You feel the constant rough ride - subtle as it is - and then the car suddenly lurches now and again, though it's not the gears or engine - I think it's the vibration/bumpiness getting worse now and again. Could it be tracking on the wheels? No uneven wear on the tires, although this only started happening about 5 weeks ago...I'm just loathe to take my dealer's word for it and spend multiple hundreds of bucks on something that I'm just not seeing as the problem...

 

[Themightyquinn]

can you post some good pictures of all 4 tires? Wouldn't hurt to have them balanced at a tire shop. Take them off yourself and save some labor costs.

 

[Flag Gibby]

Given the climate you drive in, yes your tires can lose their flexibility very fast and harden causing the vibrations that you are experiencing and the sidewall cracks. To say that it is a waste of time to get them balanced is not true, they can be road balanced and the vibrations should go away for a while. However, once the tread is below 4/32 (along with the sidewall cracks) it is possible that the tire/tires is worn enough to not warrant keeping on the vehicle anymore considering the extreme heat that they are regularly exposed to.
As far as the lurching goes, along with you stating that it is not the engine or transmission, really doesn't point to tires at all as being the problem, but I guess it is possible in extreme cases that the sidewalls could be so stiff that the tire is slipping on the rim causing momentary loss of acceleration (not a very likely scenario in my mind).