if I got from 23570R16's top 25570R16's do I need to think about changing to 4.10's?

You don't HAVE to, but it's not a bad idea.

When I went form stock to 245/75, my 5th gear (manual trans) became useless for anything other than flat highway maintaining speed. I don't mind, because I can drop to 4th, with is about the same gearing as 5th used to be. I recently got a bonus check and am using it to go to 4:10s, but I was fine for the past year with 3:73s.

Personally, I'd leave it as is for a while and see how you feel, then decide later if you want to upgrade.

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-oooooo- ---Craig, L.O.S.T. #CT068103
/______\ ---http://jeep.allgris.com
O||||||||O ---'02 Sport 4x4, 5-spd,
[]--------[] ---2.5" BDS lift, 245/75/16 MT/Rs, Moab Rims, Locked and Regeared!
[]_____[] ---The list got to long, go to my web site for more!

I run 255/70/16 size BFG M-Ts on my rig and still have the 3.73 gears. It drives around town and on the trails i've taken just fine. When ever I get the fundage for such a switch though I might just do that...but then again i might just wait for an sfa conversion in 4 years...

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Had 2005 KJ Rocky Mnt. Edition (destroyed)
Had 2006 KJ Sport 4x4
Have 2007 JK 4-dr Sahara 4x4 (tow package so stock 4.10s!!)
AEV 3.5" RS Lift; Schrockworks FR bumper and Warn 9.5ti winch; Cobra 75 CB; Rigid 50" LED light bar; Adventure Trailers (AT Overland) JK Kitchen setup in the cargo area.
Southern L.O.S.T. # 236487