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2011 Optima SX & 2002 Pontiac Firebird Formula
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Discussion Starter · #1 ·
At 50K swapped out the 2011 SX's Nexens for BFG Sport Comp 2 in the 235.

The Good: Car is noticably more capable and confidence inspiring in a spirited mode. More capable dry or wet. In fact had a nasty little wheel hop trying to take off a bit too quickly in the rain yesterday. I know wheel hop is horrible for parts, so I will be careful not to repeat. Fortunately it doesn't rain much in Southern California. The Nexens would have just spun in the same senerio. Dry- 35 mph sharp right turn, car is able, tires are compliant, not going to experiment faster than that without a need ;).

The Bad: I have a very consistent driving style and commute into work. Having run at least 8 full tanks of fuel since the new tires the MPG is down 3.5 on average. Was right around 30 mpg before and now at about 26 to 27. I was floored at first and thought it was a fluke, but tank after tank is yeilding the same results. My mileage is about 90% highway 10% city. My left pull issue is back. Car has a build date of December 2010 if I remember correctly, had the left pull from day one, long story short, it was somewhat corrected, and NOT to my surprise, as soon as I got new tires the left pull was back. Paid KIA a $100 for an alignment, and it made no difference. At highway speeds the car pulls left. It is an issue with the electric steering assist, a fix for which KIA to my knowledge has never addressed. It's a software issue and not hardware. Folks suffering from this have probably figured out that if on a level roadway at say 70 mph, if they "flick" the wheel to the left and let go, they can send the car into a left drift. This is because as the KIA Engineer who road with me in my car back in March of 2011 explained the car thinks it still wants to go left and does not reset to 0 degrees or whatever but is a degree or two off. Thanks KIA, can we expect a fix anytime soon, or do we have to get nasty about it :)? I see it as a Safety Issue myself, and I am afterall a Safety Manager by trade.
 

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2011 Optima SX, Tech & Premium Touring
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570 Posts
Yeah, my left pull is more noticeable with the same tires too, but mine has always had some left pull. Now after having a 2013 LX rental with NO LEFT PULL, I am thinking they got their act together and know how to fix this. My left pull is much more noticeable with colder weather/tires and reduces once warmed up. My MPG is probably down a little too, but performance is much better too. Worth it to me!
 

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2017 sportage sx
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448 Posts
Arctic-just for a few minutes work, try swapping the new BFG's front to rear and/or side to side. Adjust pressures as needed.
Let us know if you do.
 

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2008 SpectraSX, 2014 Optima LX,2006 Jeep Liberty, Linux Mint Mate
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6,959 Posts
The Nexens don't have the grip (read as less road friction) that the BFGs do...
Better traction (possibly softer rubber), More road drag, and lower miles per gallon..

When I replaced the "stock" Rikens (junk) with Michelins I noticed a drop in mileage on my o6 Spectra SX...but I'd gladly trade that for the MUCH improved handling, rain handling, and massive reduction in road noise..The car is MUCH safer to drive.

I road with a friend that has a new Toyota Prius and with it's skinny tires (read as lower road grip and friction) then drove my 06 Spec in the same snow...I'll take the wider, higher friction tires any day..

More road contact also means any built in alignment errors will be compounded because the side with the error can pull more.

Codger also has some good tips on rotating the tires.
Dave
 

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2011 Optima SX & 2002 Pontiac Firebird Formula
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491 Posts
Discussion Starter · #5 ·
Thanks for the responses, and I agree that the increase in handling outweights the drop in MPG. I would buy the exact same tires again if I had to do it over. What shocked me a bit is how much of a MPG drop can occur with just a tire swap, I was a little ignorant of that. With gas at $4.25/gal here in SoCal and the amount of driving I do, it starts to add up. With about 3000 miles on these new tires I will probably have them rotated in another 3000 and report back in and see if it makes a difference in the left pull.
 

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2011 Optima SX, Tech & Premium Touring
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Yeah, ANY OEM fitment tire will always be less rolling resistance to increase the MPG for the US CAFE standards. I would expect most aftermarket tires to have fewer MPG's.
 
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