My 2005 TL 5AT has been vibrating badly (13,000 miles) when cold. The vibration alleviates after driving for about 2 miles. I increased the front tire pressures from 32 PSi to 37 Psi. No more vibration or flatspotting & car handles alot better without sacrificing ride comfort or harshness. Rear tires are set at 33 PSi.

 

Just keep an eye on your tread wear pattern .. not saying it will happen but you might see more wear on the center of the tread . Also if you can do a bit of a burn out to see if your contact patch is even. Uneven tire contact patch can mean poorer braking and wet weather handling.

 

It can be difficult for many drivers to discern vibrations. Especially from a car that has reports from both driveline and tire vibrations (don't most!).

Flatspotting to some degree is a characteristic of low profile tires. Not all people have them or notice this condition, but it varies depending on the tire, psi setting and other variables such as temperature and time car had been sitting and even road texture.

My TL has OEM Michelins which, in my opinion do not flatspot beyong a slight warm up tremble for a mile after the vehicle sits about 8 hours or more (typically overnight or all day at work).

Some cars will exhibit a flatspot at all speeds, while others do not. When I noticed it I was concerned it might be driveline related as the tires had been balanced and it only occurred when I hit 50 mph, again disappating after about 1 mile. I work right off an expressway, so I was typically launching from my parking garage onto the highway without much time for the tires to warm up. It was consistent behavior, as was my driving pattern. But once the tires warmed up, I could not get any vibration to return, at any speed.

I had satisfied myself that this was the tires, and not the drivetrain. After research further (thanks AcuraZine members!) I decided these low profile tires were hyper sensitive to psi setting. I decided to experiement with the tire pressure and found that as little as a 1 psi change really made differences in ride, performance and general driving characteristics of the TL. A bit of a pain, but was a very educational process! A digital TPM is a must!

For my 05 5AT TL with OEM Michelins, I finally settled on 34psi up front and 32 psi behind. I actually was able to eliminate this warm up vibration (I think it was also 37 psi up front), but I found the ride too 'communicative' on Florida's coarse pavement. So I dialed back a bit to where the ride was on target with my tastes and the warm up vibration was barely perceptable for about .5 miles.

Any other car I would have just adapted and accepted. For some reason the TL eggs me on to do stuff like this! I am glad I did, and like you making the effort has rewarded me with better results and better understanding of the TLs attributes.

Can you imagine the 'road tests' I will be doing when I decide to change the tires to another model, brand or size! DOH!