69thunderbird

with a 3.8 motor - what is the difference in torque, mpg and speed? anyone have actual performance specs?

I have a 2007 4 door with a 4:10, but appears the 4:10 is not an option available in the X anymore. I'm getting a 2008 with a 3:73 and wondering if i should swap out before getting rid of the 2007.

Does anyone know whay they changed to 3:73? Is it because the motor couldn't handle the higher gear and constantly down shifts and revs up at speeds above 60?

JackMac4

I'm sure its a MPG issue...the 4.10s obviously lower the fuel economy, and now with the tougher laws on reporting MPG..they probably couldnt afford the PR drop in MPG.

That'd be my guess why they arent offered...

rdss

I had the 4.10's in my 07 two door and liked the extra pull it had. The 3.73's in my 08 Sahara Unlimited are finally starting to grow on me, but still not as impressive as the 4.10's. On the Interstate with the 4.10's running 75 I was at 2,950rpm and with the 3.73's, I am at about 2,550 rpms. The ability to pass without dropping into fifth was an option with 4.10's and out of the question with 3.73 if you have to do it quickly. I really can not compare gas mileage because of the gear change along with the weight differences between the two and four door JKs. The two door would get 19-20in the city and 23-24 on the Interstate and the Unlimited with under 700 miles is getting about 17-18 with mixed driving. When my 08's warrenty runs out, I might think about getting 4.10's or better. Hopefully this helps.

Rick in Colorado

Won't it be a long wait given the lifetime powertrain warranty on the 2008s? Sorry - I couldn't resist.