QTI to QTII gear swap help

[Ross]

I have the 3.7L with the 3.07 gears. I was wonderin' where I could get the gears to do a swap for the QTII gearing. I have a friend who works at an offroad jeep shop who could most likely install the gears for me. My only breaking point is price, so hopefully without having to pay for an install, it won't be too pricey.
Thanks, Ross

[Sal-XK]

As far as I know there are no aftermarket gears made. You would have to purchase the gears from Jeep for what you need. Also don't forget about the programming for them I think Caleb bought a programmer for the 3.7 that does gear changes. But if not since it's a stock gear the dealership should be able to make the change on that.

[cmdr jim]

I have the 3.7L with the 3.07 gears. I was wonderin' where I could get the gears to do a swap for the QTII gearing. I have a friend who works at an offroad jeep shop who could most likely install the gears for me. My only breaking point is price, so hopefully without having to pay for an install, it won't be too pricey.
Thanks, Ross

07JeepXK has helped a friend swap gears in there 3.07 WK. You can go 3.55 or 3.73, Yes you will have to buy the front gears from Jeep or find a used front differential or gears. The rear is a Chrysler 8.25 differential with 29 tooth spline. Those are available aftermarket. If you're going into the rear end put in some type of locker while it's open. Lastly, according to 07JeepXK, a HyperTech Speedo Calibrator or MAX Energy Programmer is needed to program in the new gear ratio.

Note: I will have available in a couple weeks a used set of 3.55 front ring and pinion gears with about 35,000 miles on them and a new set of Mopar 3.55 rear ring and pinion gears for sale, if anyone is interested, I can give you a good price on these. The Front new is $855 from a dealer and about $600 shipped from an online Mopar parts store. The rear would go for $462 or $350 shipped. I could do $300 for the set, that includes shipping.

[07JeepXK]

07JeepXK has helped a friend swap gears in there 3.07 WK. You can go 3.55 or 3.73, Yes you will have to buy the front gears from Jeep or find a used front differential or gears. The rear is a Chrysler 8.25 differential with 29 tooth spline. Those are available aftermarket. If you're going into the rear end put in some type of locker while it's open. Lastly, according to 07JeepXK, a HyperTech Speedo Calibrator or MAX Energy Programmer is needed to program in the new gear ratio.

Note: I will have available in a couple weeks a used set of 3.55 front ring and pinion gears with about 35,000 miles on them and a new set of Mopar 3.55 rear ring and pinion gears for sale, if anyone is interested, I can give you a good price on these. The Front new is $855 from a dealer and about $600 shipped from an online Mopar parts store. The rear would go for $462 or $350 shipped. I could do $300 for the set, that includes shipping.

Like stated by cmdr jim, your best bet is to get an entire front differential from a junk yard that already has 3.73 gears installed. That makes the swap so much easier and costs a lot less. All you have to do is drop the front diff and swap in the new one. As for the rear my buddy Jay purchased 3.73 motive gear ring and pinion for a chrysler 8.25 rear end. After everything is installed, purchase the Hypertech Speedometer Calibrator and change the gear ratio from 3.07 to 3.73's and enjoy! The Hypertech Speedometer Calibrator is upgradable to the max pro so you can tune your 3.7 liter at the same time. Jays 3.7 Liter WK has been rolling around with 3.73s with ablsolutely no issues what so ever and his gas mileage has even increased. He has a 4 inch BDS lift with 33x12.5R18 Toyo Open Country MT's.

[cmdr jim]

After my transfercase swap this will be my next change, with a ARB locker in the rear and a "modified to work manually" ELSD in the front. Picture this, a 3.7l V6 with swapped gears, a manually controlled transfercase and manually lockable on all 4 corners. Rubicon like minus the transfercase 4:1, only 2:72, and a few other items....

[07JeepXK]

That will be one sick Jeep. Pick up a set of JBA shorty headers and tune your XK and you will be set!

[cmdr jim]

That will be one sick Jeep. Pick up a set of JBA shorty headers and tune your XK and you will be set!

I have the JBA headers, they have been on about a year, A Fastman throttlebody, K&N cold air kit and just recently, the Hypertech Max Energy programmer. No cat back changes yet, never cared for the sound of a V6, rather be quiet.
Liking it, will like it better with the 3.73 gears! I need to add all my mods to the signature.

[07JeepXK]

I have the JBA headers, they have been on about a year, A Fastman throttlebody, K&N cold air kit and just recently, the Hypertech Max Energy programmer. No cat back changes yet, never cared for the sound of a V6, rather be quiet.
Liking it, will like it better with the 3.73 gears! I need to add all my mods to the signature.

Sorry about that. I forgot you were the one running the JBA Headers. Sounds like you have a nice setup. Get that transfer case in there and those gears. What lift are you running or are you still stock?

[cmdr jim]

Just the RC 2" with Rusty's leveling plates up front.

Hey look my signature showed up!

[Ross]

I am very interested in those 3.55's. What are the losses with going with that setup instead of 3.73's?