Originally Posted by sam617
Yes Vibration at 40MPH up. Sometime there's little vibration and other times a lot/heavy vibration. Rust must of build up behind the balancer due to salt roads here in the northeast.

I didn't want to have to make a new thread, but need to get some input right away. Hopefully someone can give me some insight. (04 6mt) I have this symptom quoted above. Odd thing is that my vibration/shuddering feel is only happening when i first start driving for the first couple miles then it goes away (even worse now that the weather is a lot colder). I have confirmed its not my tires (All DWS front 2 new and rear have 17k mi, i then rotated the new to the front thinking bad new tires, but same symptom) and my axles have just hit 150k miles so i'm thinking this is my issue, but its an odd symptom. I do have a slight shake in the steering wheel when accelerating quickly as well, which i believe is a symptom of bad axles. Thoughts anyone? Appreciate any input

 

shaking on acceleration points to axles.

If it goes away as the car warms up, it's flat spots in the tires that are worked out as you drive. Bump up the air pressure 1-2 PSI and it should help.

Get the DWS balanced again and make sure the shop mounted them properly. They should be butter smooth until 120MPH and it sounds like you have off balanced wheels. The TL is very sensitive to tire balancing and you should use a shop that uses the HUNTER ROAD FORCE BALANCER. These apply a load to the tire during the balance process to get more accurate results. It has worked to cure vibration issues for years with the TL.

My front DWS's were off by a few grams and I felt the shakes.

 

Yeah i used belle tire, but i'm not sure what balancer they use, ill have to ask. Maybe ill call other shops, but the balancing won't solve the flat spot issue. Is there anyway that you can pin-point which tires have flat spots? I mean my new ones only have 4,500 miles on them, so it can't be those 2. But this seemed to all begin when i had my 2 tires put on. I feel like this car is constantly giving me mysteries i can never solve That's exactly what i did earlier this year trying to figure this out. I had all four tires re-balanced and it didn't solve anything. So is it with confidence NOT my axles causing this nasty vibrating/shuddering feel when i first start driving? I would think it would do it all the time if it were the axles, not just stop after driving for a few miles.
To note:
1. vibration/shudder doesn't go away when pushing in the clutch and coasting.
2. Feel it at speeds of 45-50 and above

 

I don't think axle vibrations change with temperature, and the dead giveaway of a bad axle is that the vibration happens the worst at a certain speed range.

I've got a 6MT as well and am currently driving on a bad axle. The vibration characteristics are identical in 20F ambient and 80F ambient during my commute (30-60 mins) which gives everything time to warm up. It vibrates quite strongly at 59-64 MPH, and is very slight, if barely noticeable, elsewhere in the speed range. The harder you accelerate through this speed range, the more powerful the vibration. I agree with the above suggestion to re-balance the tires first. If it really goes away after warming up, I don't suspect the axles.

 

Could be a bent rim.

 

^ agree, it could be a bent rim

Flat spots happen over night when the tires sits on the cold ground! Once you drive a few miles and the tires warm up they should be fine!

Are you feeling the vibration in steering or in seat?

If steering, it's the front wheels
If seat, it's the rear wheels

Also, how are your front compliance bushings? Misc vibrations occur from worn mounts such as the 3 engine mounts and 2-3 transmission mounts. Also since you are 6spd you have a shock damper on the engine to reduce vibration that's probably worn.