CentOS 6.5 ships with kernel 2.6 and it's a quite old for now(CentOS 7 already comes with 3.10),but compile a kernel on CentOS is a mess and it's not recommended. But fear no more,guys fromElrepo took care of that for us and made a package,let's see how we can install it.

Install the kernel

<span style="font-size:14px;">rpm --import https://www.elrepo.org/RPM-GPG-KEY-elrepo.org  
rpm -Uvh http://www.elrepo.org/elrepo-release-6-6.el6.elrepo.noarch.rpm </span> 

Install the kernel

<span style="font-size:18px;">yum --enablerepo=elrepo-kernel install kernel-lt <strong> </strong></span>

Configure grub

You also need edit /etc/grub.conf to change the kernel order,change default from 1 to 0,must looks like the below:

default=0  
timeout=5  
splashimage=(hd0,0)/grub/splash.xpm.gz  
hiddenmenu  
title CentOS (3.10.55-1.el6.elrepo.x86_64)  
    root (hd0,0)
    kernel /vmlinuz-3.10.55-1.el6.elrepo.x86_64 ro root=/dev/mapper/VolGroup-lv_root rd_NO_LUKS LANG=en_US.UTF-8 rd_NO_MD rd_LVM_LV=VolGroup/lv_swap SYSFONT=latarcyrheb-sun16 crashkernel=auto rd_LVM_LV=VolGroup/lv_root rd_NO_DM  KEYBOARDTYPE=pc KEYTABLE=br-abnt2 rhgb quiet

Reboot and profit!

reboot

Now you have a fresh(not so much) kernel on CentOS.