Seams in the Road

I was faced with a rather frieghtening situation about a week ago.

I'm headed north on a highway I don't remember (I put down 2400 miles at least in a given week and am still learning the off beat highways) and I just entered into a construction zone that has the left lane shut down. The suggested speed limit is 55 mph. The road has been freshly paved but still needs some work where the crown of the driving surface meets the shoulder.

Now where the driving surface meets the shoulder there is a seam that seperates the two surfaces and maybe a 1/4 of an inch difference in elevation between the two. It could be less, but it was hard to tell from in the truck. Regardless it really didn't seem like much.

Anyways, the cones to my left are hardly lined in a straight line and there isn't much room to spare especially when I come up to a cone that forces me to verge more to the right. Right over this seam.

I have the truck in 9th rpms maxed out by the governor and travelling at 55mph. As soon as my right steer tire rolls over the seam the truck reacts as if it were a motorcycle. The seam, which isn't straight, begins to track my truck and I did not expect this. So I compensated in little increments to keep the truck straight and to make way back to smooth road.

Well, that little compensation had a much more dramatic force on the truck and trailer than I had expected and I started pulling to the left really hard. So, I tried to just keep the wheels straight. That's it, but the effect caused my truck now to verge right again.

This is all happening really fast. Ultimately it felt like I was driving on wet glass for a moment. I eased on the breaks and slowed down to 45 mph but still felt the sensation of driving on wet glass while the passenger side tires were on that seam. So to try and be more safe I decided to straddle the seam and avoid driving on it all together.

Before I was down to my safe speed after hitting that seam I thought I was losing control. It definitely felt like I was going to end up in the ditch. And in just a matter of seconds.

Has anyone else had this experience with road seems or lines in the road?

I find it amazing that they have such influence on a big truck.

I should add that the load I was hauling was lite.

I thought it would be good to share this experience in hopes to for warn anyone who isn't aware of road seams on semis.

 

Let me address the rpm issue.

I run a company truck that has many restrictions on it. In 9th gear when I am not climbing a hill the engine rpm is governed to go no higher than than 1500 rpms. At times this is a hassle and other times it is convienent. When the speed limit is 55 mph I throw the truck into 9th gear. If I am 10th gear going 55 mph and I have a decent load on the truck it is just going to lug and wear on the motor more than it needs to. So it is merely a habit of mine based on how my truck acts to leave it in 9th and ride 55 mph. It is not out of incompentence.

Okay. Now I didn't blame anything on anything in this situation. Yes it was a desolate construction zone and I initially felt safe to go the speed limit that was posted for this section of road. Until I hit that seam, which was an entirely new experience for me as a semi driver. Forgive me for learning from my experience and sharing what I learned so that others may possibly learn from it as to not be surprised like I was.

I didn't get out to measure the seam so the number I threw out there is fairly arbitrary. But I will tell you that there was no noticeable thump of any kind indicating a huge drop.

As stated in the original post, I did straddle the seam and let my right tires ride the shoulder.

The time it takes to read the post is not how slow things happened. Keep in mind I'm taking 5 to 10 seconds of detail and stretching out to give an idea of what it felt like.

Thank you to everyone else who read my post without the inclusion of ADD and understood what I was saying and shared your experience. That is really helpful to me.