Tire load rating

[ctrlraven]

I am going to be buying some new front tires soon and have been looking at the KDW2 ones.

The size I am going to get is 255/45-18. I was looking on tirerack.com and I saw that they have two different ones.

Would either one work fine on the MM or would the bigger load rating be needed? There is only a $10 difference between them.
My current rear tire is a 255/55ZR18 with a speed rating of W.
<!--Check to compare--><!--Photo and Warranty --> <!-- Sidewall info, includes sidewall shown --> <!-- Size, Load and Speedrating --> <table border="0" cellpadding="3" cellspacing="0" width="760"><tbody><tr><td align="center" valign="top" width="19"><input name="compareList" value="21" type="checkbox"></td> <td align="center" valign="top" width="75">http://www.tirerack.com/images/tires/bfg/bfg_gforce_ta_kdw2_ci2_s.jpg (http://www.tirerack.com/tires/tires.jsp?tireMake=BFGoodrich&tireModel=g-Force+T%2FA+KDW+2&vehicleSearch=false&partnum=545WR8GFTAKDW2&fromCompare1=yes&place=21)http://www.tirerack.com/images/headers/stars/3.5.gif</td> <td align="left" valign="top" width="75">Sidewall Style: Blackwall

</td> <td align="left" valign="top" width="542">
Size: 255/45ZR18
Serv. Desc (http://www.tirerack.com/tires/tiretech/general/servdesc_pop.html): 93W Load Index 93 = 1433lbs (650kg) per tire
Speed Rating “W” = 168mph (270kph) (http://www.tirerack.com/tires/Compare1.jsp?sortValue=1&resultsNumberSelected=Y&displayResults=10&compare=true&compareList=&RunFlat=All&goWhere=%252Ftires%252FCompare 1.jsp&sortCode=&width=255%2F&ratio=45&diameter=18&startIndex=20#)
Load Rating LL
UTQG (http://www.tirerack.com/tires/tiretech/general/utqg_pop.html):</td></tr></tbody></table>
<!--Check to compare--><!--Photo and Warranty --> <!-- Sidewall info, includes sidewall shown --> <!-- Size, Load and Speedrating --> <table border="0" cellpadding="3" cellspacing="0" width="760"><tbody><tr><td align="center" valign="top" width="19"><input name="compareList" value="22" type="checkbox"></td> <td align="center" valign="top" width="75">http://www.tirerack.com/images/tires/bfg/bfg_gforce_ta_kdw2_ci2_s.jpg (http://www.tirerack.com/tires/tires.jsp?tireMake=BFGoodrich&tireModel=g-Force+T%2FA+KDW+2&vehicleSearch=false&partnum=545YR8GFTAKDW2&fromCompare1=yes&place=22)http://www.tirerack.com/images/headers/stars/3.5.gif</td> <td align="left" valign="top" width="75">Sidewall Style: Blackwall

</td> <td align="left" valign="top" width="542">
Size: 255/45ZR18
Serv. Desc (http://www.tirerack.com/tires/tiretech/general/servdesc_pop.html): 99Y Load Index 99 = 1709lbs (775kg) per tire
Speed Rating “Y” = 186mph (300kph) (http://www.tirerack.com/tires/Compare1.jsp?sortValue=1&resultsNumberSelected=Y&displayResults=10&compare=true&compareList=&RunFlat=All&goWhere=%252Ftires%252FCompare 1.jsp&sortCode=&width=255%2F&ratio=45&diameter=18&startIndex=20#)
UTQG (http://www.tirerack.com/tires/tiretech/general/utqg_pop.html):</td></tr></tbody></table>

[rayjay]

Interesting question. Seems logical that the higher rated tire would not flex as much in cornering. I think the speed rating between the two isn't worth consideration as not much chance you'll be approaching the limit for a sustained period of time. Whats the wear factor difference?

[magindat]

The load rating and speed rating are int he sidewall. On-the-road tread compound is the same. One is not harder or softer than the other.

I have the same choices both front AND rear with my split set up (18 front 20 rear) and will opt for the higher load rating on both.

Only tire rack calls these KDW2 The REAL name is KDWNT.

[ctrlraven]

So the load index of 99Y would be better to get?

[Breadfan]

Yes the sidewalls will be stiffer. If you were to notice anything you'd notice a stiffer ride, probably better handling. On these heavy cars I would recommend the higher load rating for sure. The last thing you want is sloppy sidewalls when trying to take a turn.

[ctrlraven]

Makes sense, thanks Mike.

[magindat]

On these heavy cars I would recommend the higher load rating for sure. The last thing you want is sloppy sidewalls when trying to take a turn.

My feelings, precisely.

[Breadfan]

Makes sense, thanks Mike.

No prob hope you like those tires :up: