: Death Wobble?



jcollege
08-15-11, 08:53 AM
I am driving down the freeway yesterday, in the rain, and as soon as I hit 65mph, the car starts shaking violently. I speed up to about 80 to see if it will subside, but does only slightly. So I keep it under 65 for a while. The rain stops and everything is now dry, when I pass 65 everything is smooth. Does anyone have an idea to what could be causing this, my thought is unbalanced tires, but why would this ONLY happen in the rain, and not when it is dry?

odla
08-15-11, 10:52 AM
check to see if one of your wheel weights fell off.

Faber
08-15-11, 12:49 PM
I would think a lost wheel weight would cause issue regardless of rain/shine. Possibly you had picked something up on the inside of the wheel well - the old "My Cousin Vinny" syndrome - that the rain washed away. Directional tire mounted in the wrong direction - seem a few mess this up when rotating tires absent mindedly. Or possibly just tires that are poor in the rain...

jcollege
08-15-11, 01:21 PM
I am running Nitto 555 they are all mounted correctly, but will go and get them balanced again this week

cvettr/cts-v
08-15-11, 01:33 PM
is the tread good? Could they have been loosing traction in the rain and then grab enough in the dry? could it have been just a stretch of road that had oil or something else on the surface that had not been washed away by the rain yet? There are a ton of reasons for this to have happened. I'd try different highway if possible if you can next time it happens to be able to start ruling out things. Of couse that is easy for me to say sine we have 3 major highways and an innerbelt all within close proximity of each other to do comparison tests. Good luck in your search.

DDS rollin a CTS
08-15-11, 03:57 PM
It sounds more like a traction/road condition issue to me than an equipment (tire balance) problem. If a wheel was out of balance you would have had the same effect on dry pavement as well. My guess is that you were hydroplaning and or slipping a bit across crack sealant more than anything else.

awdtalon92
08-15-11, 08:16 PM
I had the same issue, and took the car to get balanced. I had just received delivery of it, so had no idea what to expect.

When it was on the lift the tech took me over and asked if the car was shaking on the highway, he said he could tell just by knocking on the rear tires. It was alike a balloon. He said that one I get to a certain speed they start to bounce uncontrollably. Got w new tires, moved the fronts to the back, and the car is a freaking blast to drive, like I expected it to be.

Not saying this is your problem, but it's a possibility.

Aurora40
08-16-11, 07:55 AM
It sounds more like a traction/road condition issue to me than an equipment (tire balance) problem. If a wheel was out of balance you would have had the same effect on dry pavement as well. My guess is that you were hydroplaning and or slipping a bit across crack sealant more than anything else.
Yeah, especially considering how heavy the rains we had on Sunday were, and the fact you have Nitto 555's. It sounds like they couldn't handle the volume of water.

Faber
08-16-11, 09:35 AM
I was chatting with some others and they had similar issue (dry weather though) and were informed that it was a broken belt in the tire. doesn't make sense to me since I thought the belts were imbedded within the tire, but then again, I'm not a tire guy.

DDS rollin a CTS
08-16-11, 11:34 AM
Like with the possibility of a balance issue, a broken belt would cause a wobble regardless of if it were wet or dry. Since the problem went away when the road dried out I still stand by hydroplaning/traction issues being the culprit.

Mystical_Ice
08-17-11, 10:42 AM
HAHA i love this: "as I hit 65mph, the car starts shaking violently. I speed (http://www.cadillacforums.com/forums/#) up to about 80 to see if it will subside".

Because of course, when your car starts shaking violently, there's no other option but to speed up to see if it stops! haha love it.

Sorry, i really hope you get it fixed. I have no idea why other than that the tires are mounted the wrong way, but I think someone mentioned that already.

amunderdog
08-17-11, 11:54 AM
Hydroplaning
http://www.smartmotorist.com/driving-guideline/hydroplaning-aquaplaning.html