Just bought a 2012 4 door JK it already had a 4in rough country lift on it and 37" tires, the spare is still the stock spare. I'm looking into buy the hyline back bumper/oversized tire carrier to hold the 37" spare, with a new front bumper with a winch, at what point do you need to start thinking about changing the gear ratios with all the extra weight. I'm pretty sure it still has the stock 3.8 gear ratio.

 

After you drive it with the 37's and decide that the improved performance outweighs the cost.

 

X2 on this...

 

Ok thanks guys. it drives well now, it doesn't seem like there a lack of power, how much would it be for a swap to D44 and would it be worth it?