I used the search bar, but for this, I have no idea what to even type. I couldn't find anything really.

So i was recently out of the Jeep community. I sold my '08 - 8 months ago, picked up a new Tacoma, and regretted it ever since. This past saturday I found a jeep I wanted (2012 Unlimited, sport, modded), called the dealership and picked it up. Only problem is the guys didn't know what exactly is on it. I know from my old Jeep, that there is at least a 3 inch lift, running 35" Toyo MT's. ARB front and rear bumpers, with a winch on the front. There's an aftermarket exhaust as well, and a snorkel. I don't care for the snorkel, but it came with the Jeep. Exhaust makes me reminisce about my cousins' 03 Cobra. Almost sounds like a V8. Almost.

But the real question is this: It's regeared. I'm absolutely certain. ARB diff covers, more power everywhere. I pull in every single gear going uphill. With this much weight on it, my old 3.21's on my 2008 would only pull uphill in 2nd and maybe 3rd. I've written some stuff down if anyone can help me.

60mph, going about 24-2500 rpm
65mph, going about 26-2700 rpm
70mph, going about 28-3000 rpm. again, keep in mind the 5-35's, steel tire carrier, and front and rear ARB bumpers, with the winch in front.

Does anyone have any idea on what gears i'm using now? I'm calling the dealership tomorrow, to ask the service department if they have any sort of records on the rig. I'll post pictures, absolutely. Just have to update my profile and stuff with the new rig.

I've read in some threads that people skip gears after regearing. I do that all the time now. I mostly start in 2nd, skip to 4th, and then 6th. But even with 6th, I can go like 40mph, not bog down, and eventually get up to 60mpg, just takes a bit.

Any ideas?

I'll update my profile and sig tomorrow or something after i get some pictures up. Also will be taking pictures of any model numbers or barcodes i can see, to figure out what the hell has been done to the rig.

 

I have 35s & 4.88s 2door 3.8 manual this picture is in 6th gear if that helps


You can jack the rear end up, both tires. Turn the tire and count the drive shaft rotations

 

It sounds like you have 5.13s installed.

http://www.grimmjeeper.com/gears.html

 

You don't need to search, just measure the tires (actual measured height, not mfg spec), get an actual rpm @ 70 mph (not somewhere in a 200 rpm range, the rpm at 70), open the FAQ's, scroll down to the rpm charts, find the chart for your engine/transmission, and plug the numbers in.

Or, spin a tire and count the revolutions.

 

The picture posted before wont help. Its from a JK with a 3.8, and a different transmission with a different overdrive ratio.

This picture might help. Its from my Jeep, with a 3.6, auto trans, 4.56 gears, and 35" Toyo MT tires.



If I were placing bets, I would bet you have 4.88 gears.

 

Allow me to place a helpful picture




If ya cant see it or download it here is the page Google gave up

http://www.tnjeeps.com/topic/1052-je...earing-charts/

 

The 6 speed is the same in both the 3.6 and 3.8. His rpms are to high to have 4.88. The big question though is if his speedo is calibrated. If its not then your not going to tell by using the speed and rpm.

Sent from my SM-G900V using Tapatalk

 

I'm 90% sure the speedo is calibrated. I haven't done a GPS test yet, but I found the box for a procal in the back. No unit tho, so I won't be able to recalibrate if I change anything. But I'm going to ask the dealership's service and parts desk for any and all paper work they have on installs or anything. The guys in the showroom don't know much. Seemed like the finance guy knew more about cars than my sales guy. But thanks for the info guys. I'll have to use the chart or try the tire rotation thing tonight. I missed you guys!

 

What sort of black magic is this. Brake on, ~74 mph?!

 

Other than my pledge to the dark Prince....
I have a bad wheel sensor or something that makes my dash light up