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Topic Review (Newest First)
05-05-2013 08:54 PM
jadmt
Quote:
Originally Posted by Tweak View Post
I'm sorry but I'm having trouble understanding your post. I never said anything about it coming from the factory.
you wrote this.

"this cant be true. let me share what happened to me.

I bought my jeep brand new off the lot thinking I had 3.21's. after installing 37's I found that it really wasnt that bad to drive. something had to be up, so I checked my build sheet. sure enough, I had 3.73's! for some reason my jeep came with a procomp branded hypertech programmer that tunes the computer for gears and tires. I changed the gears setting from STOCK to 3.73 and now it drives a hell of a lot better. shift points are just beautiful"

The "for some reason my jeep came with procomp yada yada" threw me.
If you would have replied for some reason the dealer included it then I would have understood.
05-05-2013 07:55 PM
Tweak
Quote:
Originally Posted by JTPhoto JK View Post
New programer was added Probably because they put new wheels on at the dealer. You need the programmer to set tire size.

To the OP have the dealer purchase a ProCal for you and use that to reset the gears and tire size.
did you miss the last half of my post?
05-05-2013 07:54 PM
Tweak
Quote:
Originally Posted by jadmt View Post
the what was a dealership add on not a factory add on. Many things are added at the dealership level that have nothing to do with being factory.
I'm sorry but I'm having trouble understanding your post. I never said anything about it coming from the factory.
05-05-2013 07:07 PM
thegreyman
Quote:
Originally Posted by kdgreene View Post
there are two tow packages:
the normal tow package is hitch and wiring with 3.21 2000 lbs capacity
max tow is hitch and wiring with 3.73 gears 3500lbs capacity


Good to know. I checked I have the 3.73 with the tow package
05-05-2013 10:19 AM
JTPhoto JK
Quote:
Originally Posted by Tweak View Post

no idea. I got the "off road package" (yea fine they hustled me out of a few bucks) that came with new wheels, MT tires, sliders, light guards, etc. and it was just sitting in my glovebox. I feel like it was part of the deal that the salesman didnt really know about. I know a girl who got the same jeep, same packages, at the same dealership around the same time, hers didnt come with one.
New programer was added Probably because they put new wheels on at the dealer. You need the programmer to set tire size.

To the OP have the dealer purchase a ProCal for you and use that to reset the gears and tire size.
05-05-2013 06:15 AM
jadmt
Quote:
Originally Posted by Tweak View Post
no idea. I got the "off road package" (yea fine they hustled me out of a few bucks) that came with new wheels, MT tires, sliders, light guards, etc. and it was just sitting in my glovebox. I feel like it was part of the deal that the salesman didnt really know about. I know a girl who got the same jeep, same packages, at the same dealership around the same time, hers didnt come with one.

the what was a dealership add on not a factory add on. Many things are added at the dealership level that have nothing to do with being factory.
05-05-2013 12:23 AM
Tweak
Quote:
Originally Posted by ohioviper View Post
Why would your new Jeep come with a programmer ?
no idea. I got the "off road package" (yea fine they hustled me out of a few bucks) that came with new wheels, MT tires, sliders, light guards, etc. and it was just sitting in my glovebox. I feel like it was part of the deal that the salesman didnt really know about. I know a girl who got the same jeep, same packages, at the same dealership around the same time, hers didnt come with one.
05-04-2013 09:13 AM
MichaelEdwardsDO And the 3.21 tow package stinks for towing in my jku with 35's. not sure about anybody else's because I don't drive them but I feel like I'm heading up hill on flat land
05-04-2013 08:25 AM
kdgreene there are two tow packages:
the normal tow package is hitch and wiring with 3.21 2000 lbs capacity
max tow is hitch and wiring with 3.73 gears 3500lbs capacity
05-04-2013 04:37 AM
Got Snow I am just going off memory here, so forgive me if I am wrong but when I was purchasing my 2011 & 2012. I believe there are two tow group options.

Tow Package
Max Tow Package

Could it be that only the max comes with 3.73???

What does your sticker say?
05-04-2013 02:37 AM
streamlinedg The window sticker showed that I was getting the Tow Group Package.
The salesmen showed me what came with the Tow Group Package from Jeeps website.
The 2013 brochure and Jeeps web site state that the Tow Group Package allow the wrangler unlimited to tow 3,500.
That said all 2013 unlimited models should have come with 3.73 or 4.10.
Jeeps Website states that the Tow Group Package includes the 3.73 ratio.


Thanks... For the info on the Procal, I will be meeting with the dealership in the morning.
05-04-2013 12:50 AM
ohioviper Window sticker. or ask for your build sheet.

http://www.jeep.com/wccsapp/universa...ull&category=U
05-04-2013 12:17 AM
thegreyman
Quote:
Originally Posted by streamlinedg View Post
Buyer beware.
Chrysler and dealership are having problems reprogramming for the new 3.73 gears they installed to replace my 3.21.

If anyone has upgraded the gears in a 2012 or 2013 please help me out here.

I purchased a new 2013 Sahara Unlimited with the tow group package because my 2010 wrangler was struggling when I was towing 3,000 lbs. I had the 3.73 gear in the 2010.

The new 2013 Jeep has 40% more house power so it made sense to buy it.
A few week after purchase I was made aware that the new Jeep could only tow 2,000 lb because of the 3.21 gears.

The dealership and Chrysler said they would upgrade the Jeep.
Now that they have the new 3.73 gears installed, the Jeep won't allow them to reprogram for the different gearing.

Chrysler and surrounding Jeep dealerships have been contacted but can't seem to fix the problem.

I hope someone can help. Thanks...

Ohh snap! How do I know which gearing I have?
05-03-2013 11:53 PM
MichaelEdwardsDO
Quote:
Originally Posted by ohioviper View Post
Why would your new Jeep come with a programmer ?
Seriously good question
05-03-2013 11:47 PM
ohioviper Why would your new Jeep come with a programmer ?
05-03-2013 09:50 PM
Tweak
Quote:
Originally Posted by JTPhoto JK View Post
I remember reading somewhere that the new computer system didn't require a gear change reprogram because the speed sensors would automatically calculate ratio due to engine rpm vs tire revolution.
this cant be true. let me share what happened to me.

I bought my jeep brand new off the lot thinking I had 3.21's. after installing 37's I found that it really wasnt that bad to drive. something had to be up, so I checked my build sheet. sure enough, I had 3.73's! for some reason my jeep came with a procomp branded hypertech programmer that tunes the computer for gears and tires. I changed the gears setting from STOCK to 3.73 and now it drives a hell of a lot better. shift points are just beautiful.
05-03-2013 09:43 PM
ohioviper He may have wanted 3.73s but the dealer ordered 3:21s or told him it was 3:73 when it was actually 3:21. I promise you the build sheet and window sticker match whats actually in it when it rolls out of the factory.
05-03-2013 09:13 PM
socal-jk I'm more worried how a jeep that's supposed to have 3.73's are ending up with 3.21's.......
05-03-2013 09:00 PM
crawlin_archer We can't change the PCM gear ratio at work. Our scan tool programming doesn't allow it, cause Chrysler doesn't want us to be able to. The Federal Emission laws are so strict now that they don't allow us to change things like this to avoid liability if you don't pass inspections and such stuff. We found this out when we changed a 2012 Sport from 3.21 to 3.73 such as yours has. We called Jeep & found out we can't do that any more. The ProCal is what you need to change it with. And no the PCM won't learn on it's own from speed sensors. It will set all sorts of gear ratio, inplausible wheel speed & various other codes. And if it's an automatic it will start shifting all crazy.

My wife's JK has 3.21s & I pull my mini stock dirt car on a dual axle flatbed trailer with it all the time w/o any issues or hesitation. The dirt car weighs in at 2200lbs by itself. Just make sure it's loaded level always leave room in front of me in case I need to stop quick.
05-03-2013 08:40 PM
ohioviper Your not the first 2013 to regear by far. The procal will set your ratio and you will be good to go in minutes. I bought my procal from Quadratec. Your window sticker is what you want to look at for axle ratio.

http://www.quadratec.com/products/17619_1001.htm
05-03-2013 08:20 PM
streamlinedg Where can I get a procal and how much is it?
05-03-2013 08:03 PM
streamlinedg No, Chrysler is paying for the parts and the dealership is covering the labor.
Keep in mine that I paid for the Tow Package Group. The 2013 brochure and Jeeps web site says a Wrangler Unlimited can tow 3,500 lbs.

I feel better after talking to them in detail about the problem.
Apparently the new Jeep Wranglers are set up with a code that must come from Chrysler so that they can go into the program and put in the correct ratio. They said as far as they are aware my Jeep is the first 2013 to upgrade the gearing.

I suspect that most Jeep owners think they have the 3.73 gears. Because they are going by the brochure. I found this out from the forum.
05-03-2013 07:49 PM
jadmt
Quote:
Originally Posted by Raspy View Post
The Procal works on 2013 models, but the dealer won't be able to use one because they are coded to each vehicle they program. Each Procal will only do one at a time and the one it did must be set back to original specs before another one can be done. So, you might have to get one for yourself.

I don't know where the speedo is measured from, but if it's axle rotations measured on the ring gear, like my Dodge, there is no calibration needed, only for tire size changes.

Maybe they can't do it because it doesn't need to be done.
it needs to be done.
05-03-2013 07:27 PM
Raspy The Procal works on 2013 models, but the dealer won't be able to use one because they are coded to each vehicle they program. Each Procal will only do one at a time and the one it did must be set back to original specs before another one can be done. So, you might have to get one for yourself.

I don't know where the speedo is measured from, but if it's axle rotations measured on the ring gear, like my Dodge, there is no calibration needed, only for tire size changes.

Maybe they can't do it because it doesn't need to be done.
05-03-2013 07:01 PM
jadmt
Quote:
Originally Posted by TOK View Post
Thought I read comments here about the Procal not working with the 2013 (yet).
works on my 2013 and has since I got it in Sept of 2012.
05-03-2013 06:51 PM
TOK Thought I read comments here about the Procal not working with the 2013 (yet).
05-03-2013 06:19 PM
JTPhoto JK
Quote:
Originally Posted by jadmt View Post

nope you need to recal with procal
Thanks for clarification.
05-03-2013 06:13 PM
JeepHerz X2 jadmt.
Procal will do it in 5 minutes. Though I doubt your dealer has one laying around. Takes 5 minutes. Swapped from 3.21s to 4.56s and changed gear ratios on my 2012 auto.
05-03-2013 06:07 PM
jadmt
Quote:
Originally Posted by NWJeeper89 View Post
would the ProCal resolve this issue?
yes
05-03-2013 06:07 PM
jadmt
Quote:
Originally Posted by JTPhoto JK View Post
I remember reading somewhere that the new computer system didn't require a gear change reprogram because the speed sensors would automatically calculate ratio due to engine rpm vs tire revolution.

nope you need to recal with procal
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