Hello! I've read this forum ever since I purchased my 2008 Acura TL last December. Since then, I have had the very loud, violent shaking/vibration while driving around 40-60 mph. It comes on slowly and progresses to a point where I have to pull over for fear that something is going to break. I've read and read about changing the fluid and 3rd and 4th gear pressure switches and have purchased the fluid and parts but am still questioning whether or not this is going to fix my problem. I have worked as a automotive mechanic in the past working on European cars and never experienced this kind of issue with a transmission problem. I have though, experienced this kind of issue with sticking calipers. Please feel free to give me your opinions and input as well as any fixes you may have found!

 

What leads you to think transmission? Does the shaking change with a change of speed? What about a change of gears? During braking? During acceleration? Have the wheels/tires been balanced recently? Have you checked all of the suspension bushings?

 

Obviously it is difficult for folks to diagnose such things over the internet, but the last thing I thought of when reading your description was the transmission. I'd be more inclined to examine the condition of your front struts and brakes before looking at the transmission.

 

The only reason I started thinking about the transmission is because of internet search replies talk about the inherent problems with this car's transmission and the shaking/shudder issues that have plagued this car. The shaking only happens about once every month or two. It does not change with change of speed or change of gears. It does not change when breaking or accelerating. I have not had the tires balanced because it is smooth as silk when the shaking is not occuring. I have not checked any suspension parts yet as it is tight and handles great when the shaking is not occuring.

 

Thanks for the input. The more I read here the more I think about a sticking caliper. Why it only happens once every month or two i can't say. Please let me know of anything else you think of that I can check!

 

I bet it's an axle

 

My thoughts exactly.

 

A sticking caliper causing shaking while not applying the brakes should show evidence of heat and brake dust and pulling to one side.

 

Why would an axle only act-up occasionally? What do I look for? I've replaced lots of axles for bad CV joints (short shaft, long shaft) due to popping when turning but never due to intermittent, violent shaking!? Please explain further!

 

Axles are notorious for shaking only under acceleration at certain speeds.

 

You will notice the shaking get more violent upon hard acceleration with bad axles and almost as if was non existent before the acceleration. Acceleration is the key word.

 

Guessing you all missed this?
I am going to vote for suspension issues. Failed strut? Thinking of bad harmonics triggering massive shaking? I really don't know...just guessing here at this point. The description of the violent shaking isn't descriptive enough to really understand what it could be. Axles in theory shouldn't shake enough to be considered "violent". Could it be the transmission shifting/slipping?? Maybe...but again, not enough details in the description.

 

If it's not with acceleration, start with a road force wheel balance and go from there. Tires can cause so many different problems and it is also one of the cheapest to check. Do you feel this violent shaking at the steering wheel or floor?

 

Yes, the steering wheel is shaking, floor not so much. Very loud noise along with the shaking. And it only happens once every month or two. Comes on slowly and progressively gets crazy!! Last time it happened, four days ago, I was driving at about 50 mph and it slowly started. After a minute or so, I pulled over to the shoulder. Braking was fine. Turned the car off and restarted it and drove back onto the highway. It continued to shake but faded away after a few minutes. Parked and went into a store for 30 minutes or so and then got back on the road to home. It started shaking again at around 40-50 mph. Toughed it out back to town and it faded away and hasn't been back since. ? That's the cycle.

 

The only car I've ever driven which exhibited this symptom had a failing shock or strut on one corner coupled with an out of balance tire.

At this point there is nothing else for us to say, you're either going to need to bite the bullet and have the issue professionally diagnosed, or start throwing parts at the problem until you get it fixed.

 

Thank you all so much for your time and input to this delima. I plan to take the car in for a rotate and balance soon even though it is smooth as silk 98% of the time. I know the owner of the shop and will quiz him and the technician as to their thoughts. I really want to get underneath the car while on the rack and put my hands on it. In the meantime, feel free to reply with anything you may think of that might be of interest to the cause!

Thanks again!

 

Get an infrared temp "gun" and check the rotor temps when problem arises.

 

Usually when its a sticking caliper, you could hear a high pitched sound, does it pull to one side when it happens? Does your brake pedal sometimes take a little longer coming back? When you get the shakiness, do you have less stopping power?

If you have any of this symptoms then, thats your caliper alright lol

 

Check your motor mounts!

 

This. And I would also check the transmission mounts too.

 

OP ~ Keep us posted!

 

Guys, recently I had been driving around town for a couple of hours and I decided to run the car through the car wash. I was drying the windows and decided to wipe the dust off of the wheels. The front left wheel was very hot and the caliper was so hot I could barely touch it. I immediately went to the front right caliper and I could hold my fingers on the caliper. Went back to the front left and it was still dramatically hotter. Even after driving through the car wash! I think I have found the culprit of the shaking at highway speed! Now I have to get to work on inspecting the brake system components! I'll let you know what I find. Thanks again to all of you for your time and help!

 

Glad you found it before it caused a massive problem...

 

Not atypical for Honda calipers; I had the same thing occur on three of the four calipers on my 2001 Accord.

 

unfortunately, the damage has already been done.
now needs:
new caliper
plus
Rotors/pads. No other way around this unless you want to pull everything apart again later down the road by skipping parts

 

Not what I meant.....

I'm glad it didn't cause an accident or fire.

 

I went to the garage to get my temp gun and it was dead. Batteries had gone bad and I couldn't get it to work again. But you were on the right track! Thanks for the input!

 

Since I have never owned a Japanese car until this one, should I stick with OEM parts or are AutoZone (et.al) parts okay? I know from experience that with my German cars, OEM parts, although more expensive, usually were worth the difference in price.

 

It depends upon the part; remanufactured/rebuilt Honda brake calipers are a very common aftermarket item which I've used on numerous cars and never had an issue with.

 

I was in a hurry/pinch and used Autozone calipers on the rear...they work fine, but look like hell due to not being coated and have surface rust.