I was thinking my 2008 wrangler 2-door x 6spd had a 3.21 differential. I emailed Jeep and they sent me my original build sheet. Turns out I have 3.73 gears. I am thinking Teraflex 2.5 budget lift and some 33's. How much will the performance be affected of my Jeep both on and off road? Is this a good idea or will 3.73 have the same affects as 3.21 for the most part?

 

You'll be fine. 3.73 is standard with a 4dr tow package so on your rig you'll pull 33's without a problem.

 

Thats what I run and it works great for daily driving and wheeling. The only place it is tough is rock crawling where a Rubicon transfer case would be nice......

 

You'll definitely be fine with 33's. I have 3.73's and I'm running 35's. While it's not ideal and I'd love to have 5.13's, I get by with the 3.73's and basically just drive with my OD turned on...I have an auto by the way.

 

I'm running 373's with 35's and it is just fine!

 

I have 33x12.50 tires, an automatic, and 3.73 gears. No loss in power at all from factory. I wheel with the big boys just fine.

 

You should be ok, slight drop in power...slight. and for an added bonus, you get a little better gas mileage on the flat/down hills. get a CAI, Cat Back, and Flashpack and you should be in Great shape, no need to re gear.

 

You shouldn't have any problem with 33s and 3.73s, especially since you have the manual transmission. Maybe a slight power loss, but nothing that's bad. As someone else said, you might notice it when off-roading in technical areas (rock climbing.)

The suggestion about adding a cold-air intake--forget that. You'd be asking for trouble and not getting much of any value from it. Most of those kits will be major issues if you off-road, greatly increasing the chances of sucking water into your engine. You could always do a snorkel, but remember that would be for cleaner air, not deep water protection. Too many electronics on the JKs for that.

 

mines drives great haven't had any problems yet

 

Excuse my ignorance but what is Cat Back?