QuestionWe own a 2009 Jeep Patriot, bought new from the dealer. It has 20,000 km or 12,000 miles. We are concerned about something it is doing and are wondering if it could have something to do with tires. It already had one tire replaced because of separation. When driving on highway on dry pavement it sometimes feels like you are on glare ice - it feels like you are losing control for no reason. Could this have something to do with the tires. We have had it in to the dealership but of course it doesn't do it when they are driving it. Thank you for your time and look forward to your response.
AnswerPat,
First let me say, I don't think this is a tire problem per se. At worst, it's the vehicle reacting to the tires - and while a fix might involve changing tires, the source of the problem is the vehicle - which may or may not be changeable enough to make it immune.
It is very important that we get the details right - diagnosing a vehicle problem over the internet is difficult enough. So did the problem start before the one tires was replaced? It doesn't sound like it - and I'm going to continue on with that assumption.
Did you have the problem from the beginning? It also doesn't sound like it, so I am making that assumption, too! It would be very helpful if we knew when it started and what transpired just before.
The next thing is the description: Driving on glare ice. My impression is that driving on glare ice means that you have to do steering inputs very slowly, and the same for braking and accelerating. To do otherwise results in the vehicle sliding. I just can not imagine that this is the case on dry pavement. Could you describe what the vehicle is doing without using an analogy?
But I am going to make another assumption, that the vehicle just feels directionally unstable. That it doesn't seem to be pointed in any particular direction. That the vehicle feels "vague".
Assuming I have made correct assumptions, the first step is to check all the tire pressures.
On every vehicle sold in the US, there is a sticker – commonly called the tire placard - that lists the original tire size and the proper pressure for that size. The placard is usually located on a doorpost or in the glove box – but sometimes it is located in the trunk or on the fuel filler door.
BTW, it doesn't matter who makes the tire or what pressure is listed on the tire's sidewall, if the tire size is the same as the placard, then the pressure listed on placard is also appropriate.
Are all the tires the same size as listed on the vehicle's tire placard and are the pressures the same as listed?
If not, then that is the area to explore.
Second step would be to check the alignment. Jeeps tend to have lots of caster - and that tends to cause what is known as a "shimmy" - a rapid back and forth motion of the front wheels that sometimes starts without provocation (sometimes by hitting a bump!), and then seems to stop when the vehicle speed is reduced.
From your description, I don't think it is that.
The next part about alignment is that my experience says that the published alignment tolerances are too wide. Not the target value, but the allowable deviation from that value. I think it ought to be half of what is published.
Put another way, the alignment should be within the inner half of the spec.
While I don't think the issue about the tolerance is the cause of your problem, I recommend that the vehicle be placed within the inner half of the tolerance to eliminate that as a potential source.
And my last bit of advice is about the drivetrain. Is this an All Wheel Drive? Part time, full time, electronically controlled? I wonder if there is a problem with that?
