There is really no risk at all to your mechanicals as long as you drive cautiously and smartly.
If there is an accident of any kind that you are involved in and you are found to be over your weights, you could face huge legal problems.
It's kind of like rear ending someone. It is your fault no matter who else did what.

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2006 4.0 5 spd auto 4x4 Super Cab
BF Goodrich Commercial Traction T/A's
Royal Purple Throughout
Alpine Head Unit with some Infinity Noisy Stuff
NW Oregon