3.6 with 37s
#1
JK Enthusiast
Thread Starter
Join Date: May 2009
Location: Texas
Posts: 361
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://www.jk-forum.com/forums/images/icons/icon1.gif)
I currently have a 07 auto jku with 35s. The jeep does fine with no hills but when I go to Colorado a 12 hr trip for me all I can say is its miserable and I am afraid the thing is going to blow up lol. I have regeared to 5.13s and it did help with acceleration but on hills it still wants to hunt gears. If I never wanted to run bigger than 37s would the 3.6 be a good option or should I wait and see what the next generation brings. I just want to be able to run 75-80 on cruise without major problems. I have also looked into an LS and it would be a more expensive option.
Sorry if this has been covered. I have been inactive for a while since I got my jeep where I want it.
Sorry if this has been covered. I have been inactive for a while since I got my jeep where I want it.
#3
JK Freak
![Default](https://www.jk-forum.com/forums/images/icons/icon1.gif)
I'm on 37" with a 2014 3.6L and 4.88 gears, I cruise on the interstate at 65 mph for the sake of fuel, I can get 13.5 mpg at 65. If I try to go 70 or 75, that number keeps dropping. I don't like buying gas. Around town I get 15-15.5 mpg.
I have no power issues or any issues dropping away from OD on the interstates.
I have no power issues or any issues dropping away from OD on the interstates.
#4
![Default](https://www.jk-forum.com/forums/images/icons/icon1.gif)
Have you used a superchips or AEV procal to account for the 37s? I had 37s on my last jeep for 4 years and never did it, have 37s on my current jeep and just did it at 7k miles and it's night and day. I can cruise at 75 without any hiccups, the new shift points after accounting for the 37s is a game Changer. It gave all the drive ability back to the jeep and I'm currently getting 17+mpg highway. I'll regear at somepoint but even the AEV procal made a huge difference
#5
JK Freak
![Default](https://www.jk-forum.com/forums/images/icons/icon1.gif)
Have you used a superchips or AEV procal to account for the 37s? I had 37s on my last jeep for 4 years and never did it, have 37s on my current jeep and just did it at 7k miles and it's night and day. I can cruise at 75 without any hiccups, the new shift points after accounting for the 37s is a game Changer. It gave all the drive ability back to the jeep and I'm currently getting 17+mpg highway. I'll regear at somepoint but even the AEV procal made a huge difference
#7
JK Jedi
![FJOTM Winner](https://i.ibb.co/FgFLpFN/Untitled-1.jpg)
![Default](https://www.jk-forum.com/forums/images/icons/icon1.gif)
If you have to run steep grades I would not go over 35's with the 3.8 auto. That set up just sucks. I run 5.13 with the 6 speed on 40's and it is the same thing. Drop to 4th gear to get up the hill.
Trending Topics
#8
![Default](https://www.jk-forum.com/forums/images/icons/icon1.gif)
I'm a 2011 jk manual 6 speed with 4.88s on 37s Nitto mud grapplers on a 4.5 aev lift. If I drop to 5th gear, I can hit over 100mph. A bit sketchy but had my axles reinforced. I have a 3.8 with over 100k miles on but she still runs strong. No engine upgrades other than a redrock snorkel. I'll send in pics next time cause I know there will be people saying I'm lying.
Last edited by RamseyPantaleon; 06-21-2016 at 04:49 AM.
#9
JK Junkie
![Default](https://www.jk-forum.com/forums/images/icons/icon1.gif)
100+ MPH in a Jeep on 37's!!! Your the man!! I'm guessing you used a TomTom or other GPS unit to track speed since the speedo was buried. My tires are only rated for 90MPH just enough to activate my Flux compasitor but I'm sure they won't spontaisly combust at 90. I think I'v hit 90 once on the Jersy T-Pike.