Hi,

I have an automatic GE8 that’s done 100,000kms. For the past few months it has sometimes been shaking reasonably badly on the motorway. It feels Iike a really badly balanced tyre.

This has happened maybe 4 times in the last 3000kms and lasted maybe 3 minutes each time - so very very infrequent.

It doesn’t really make a difference if I brake/accelerate, and so far has only happened on the motorway.

It also has happened on a similar section of the motorway each time, but I drive this exact section maybe 4 times a week, and the shaking happens maybe once a month so I find it hard to believe that the road is to blame and maybe the location is a coincidence.

Any ideas what could cause this? The fact that it happens so rarely makes me very confused. I haven’t replaced the gear box oil, maybe that’s a good start?

Thanks in advance

 

Which end of the car does the shaking seem to be coming from? Have you had the car long enough to know it's past maintenance and parts replacement? Just going from what you listed in your post, the likely possibilities, I think, would be b a bad motor mount, bad front axle or hub, or a bad tire.
You haven't mentioned your mechanical abilities, so my suggestions are going to involve a mechanic or a shop. If you have somewhere that you use to maintain your cars I'd take it there and have them do an observation first of the engine compartment with the engine running, looking at the movement of the motor mounts under a load. If nothing there is f.ound, I'd have them put the car on a hoist and go over the suspension and axles. The axles would be suspect if there's any movement in them at rest. Next, I'd have all four tires removed and spin balanced to see if there's any significant imbalance that would cause the shake.

 

Thanks 56chevydan.

I have owned the car for a few years and about 30,000 kms and in that time I’ve just replaced the tyres and done a couple of oil/filter changes. No idea before then.

I do all the work on my cars, I’ll try out your suggestions and hopefully can find something. Thanks again.

 

^^This raises my first suspicion.


My Recommendation (in this order):

1) Check tyre (we say "tire," by the way ) condition and balance. Also, if you have uni-directional tyres, make sure they were installed correctly.

2) Check alignment.

3) Check suspension.

 

Thanks Mister Coffee.

Sorry, I worded that not so well. I’ve ONLY replaced the tires. They’ve been on the car for about 10,000 kms.

Is it really very likely that suspension/tires are to blame since it’s so ridiculously infrequent? It only happens for a few minutes, every 10-20 hours of driving and is quite severe shaking - I’ve done quite a bit of rallying with unbalanced tires and wheels caked with mud and rarely had shaking this bad.

Thanks

 

I have a small section of highway near me that always make the steering wheel shake, like an unbalanced tire. But it is always in that same section of road...

I just live with it, because everywhere else, the car is fine.

So, might be the road...

 

I don't know. Maybe something is loose and causing an intermittent problem. But if the car shakes on the motorway, it has to be tyres, alignment or suspension. Or the road surface (see below). It's not going to be poor radio reception.



Funny you should mention that. Several months ago, I was driving on my usual route to my favorite discount liquor store. This is an establishment that I think of as my "happy place," but more on that another time. Along the freeway, I began to experience vibration in the car and a noise that could only be described as very loud howling. The trouble was intermittent, but disconcerting nonetheless. When I pulled off the freeway to inspect the car, I found nothing. The problem only happened at highway speed. After several freeway trips and bad noise, I went to my tire guy (my second happiest place). I asked him to give the car a quick look. He said everything was fine, and it was probably the road. He said that the state had re-sized the freeway lanes and, in doing so, they had moved the reflective broken lines that separated the lanes. This left rough patches on the highway that caused my vibration and howling. I haven't worried about it since.