Hey guys,

Whenever I drive over a bump or a pothole with only one wheel, the steering wheel jerks to the side, making a rather unsafe driving experience. This is especially prevalent when accelerating. The car doesn't veer when you hit a bump with both front wheels, however. I know this isn't a problem with my particular car because the exact same thing happens with my buddies 06 TL. Is there anything that can be done to correct this issue? I have owned three cars before purchasing the TL, and I have never encountered this before. I have brand new wheels, good ones at that, so I know that's not the issue.

Thanks.

 

1> I would get your struts checked for leaks/bends
2> check the axles and bushings for any sign of wear/etc
3> check the rims/tires for bends/bubbles/air pressure

 

Has anyone else experienced this problem and has first hand insight?

 

how hard are you trying to accelerate? does it happen going slowly over speed bumps?

you could be experiencing torque steer. but if it jerks a lot on single bumps then check suspension i guess.

 

sounds like torque steer

 

I don't believe its torque steer because I don't t have to be accelerating for the symptoms to recur and it happens irrespective of speed, albeit more dramatically at higher speeds. I also noticed that If I am going over rough roads in general the steering wheel will shimmy back and forth rather than remain poised.

 

^biggie, I have the same problem...my steering wheel steadys left and right when going over bumps during normal driving.

I plan on getting a tire rotation and balance and hope this resolves the issue.

 

compression bushings?

 

I don't think this will resolve my issue because my tires were already balanced and rotated. I read an interesting article about "bump steer" and the symptoms described are on point. Fixing it sounds like a real PIA, though. What do you guys think?

http://autos.yahoo.com/maintain/repa...ques108_3.html
also
http://www.quadratec.com/jeep_knowle...article-68.htm

 

What is the cold tire pressure in each tire, what brand/model/size of tires are on the front wheels and how much tread remains on each front tire?

 

'Bridgestone Potenza re960 as pole positions' inflated to specs with more than 75% tread left. This feels more like a suspension, rather than a tire issue.

 

^^^ inflated to what spec ??? spec in the door jam or spec on the tire ???

 

Tire.

 

try the spec in the door. If you're pumping to the max psi by the tire label you are over inflating your tires.

"Max" tire pressure on the tire should not be what you're pumping it to. The spec in the door is tailored for the weight of the vehicle (given stock wheels, etc). Different vehicles require different pressures for optimal tread contact.

these aren't like bicycle tires where higher pressure is ideal.

 

^^^ i dont completely agree bro....

80% of the max tire pressure is where i sit at....

my falkens had a max pressure of 51psi and i used to inflate the tires to ~38....the door jam says 32 which killed the gas mileage and acceleration on that tire....

now my firestone's have a max pressure of 44psi and i keep the tires at 34....still higher than the door jam....

the reason i would go by the tire and not the door jam is because NOT ALL TIRES ARE CREATED EQUALLY....you have to adjust pressure to compromise for the weight of the tire/rolling resistance/compound/etc

BTW I hope i didnt misunderstand your post....

 

true, but in an effort to isolate the problem it doesnt hurt to take it down a notch lol.

i over inflate a few lbs if i feel like i need more mpg. but if he did max he could be something like 20 lbs over recommended...which is a lot lol

keep in mind, lower profile tires typically need a higher psi since the sidewall is smaller. Larger profile tires can cope with lower pressures better.

 

^^^ true....

i agree with your point of not filling to max psi on the tire....but disagree with filling ANY and EVERY tire on your car with the spec in the door jam....

 

OK, if you have 17" wheels, adjust the pressure to 36 psi in the front tires and 33 psi in the rear tires after letting the car sit overnight.

If you have 18"+ wheels, adjust the pressure to 39 psi in the front tires and 36 psi in the rear tires after letting the car sit overnight.

Then let us know if that resolves your bump steer issue.

 

^^^ if you dont mind me asking Will, how did you come to those numbers ? Am curious to know....

 

The recommended psi for the 3G TL 6M with 17" wheels was either 35F/32R or 36F/33R depending on year, and 39F/36R was recommended for the 18" A-Specs, IIRC.

The stock wheel 3G TL with 5AT had a lower recommended psi - 33/32 or 32/32 depending on year.

FWIW, a general rule of thumb is to use pressures you are comfortable with at or above recommended psi (but no more than 40 psi), for normal daily driving. I use 37F/34R or 36F/33R on stock 17" wheels for my 5AT TL.

 

^^^ aaahh.....as i mentioned above, try going ~75-80% of the max psi mentioned on the tire....i have always loved that setting....

its well inflated for acceleration + gas mileage and doesnt carry too many bump inside, so you get a nice smooth ride