Engine swap help
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Engine swap help
Hi all. First, thanks for the add.
I am on the process of collecting components for a Cummins 4BT swap into my Jeep YJ.
I want ideally, to couple an NV5600 to the Cummins and the output end to an NP205 transfer case. All that will get mounted in the Jeep. Since I haven't bought the drive line yet, I'm trying to get a length of the tranny front to back.
I know it uses a different front mount ( to bell housing) than an NV4500 but is is the same length front to back?
Thank you for the advice.
I am on the process of collecting components for a Cummins 4BT swap into my Jeep YJ.
I want ideally, to couple an NV5600 to the Cummins and the output end to an NP205 transfer case. All that will get mounted in the Jeep. Since I haven't bought the drive line yet, I'm trying to get a length of the tranny front to back.
I know it uses a different front mount ( to bell housing) than an NV4500 but is is the same length front to back?
Thank you for the advice.
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From: vermont
The NV-5600 is at least 6 inches longer and about 200+ heavier.
I would say installing a HUGE, LONG transmission like a NV-5600 in a YJ would be a really bad choice.
The 6 speed is a slower shifting transmission that has gear spacing that is best suited to HEAVY towing, which you will not be doing with that YJ.
It is also so long your rear driveshaft will be super short and have terrible drive line angles.
The NV-4500 would be a better choice.
I bet a quick google search of "YJ with 4BT and NV-4500" or the like would get you tons of info and videos to watch.
I would say installing a HUGE, LONG transmission like a NV-5600 in a YJ would be a really bad choice.
The 6 speed is a slower shifting transmission that has gear spacing that is best suited to HEAVY towing, which you will not be doing with that YJ.
It is also so long your rear driveshaft will be super short and have terrible drive line angles.
The NV-4500 would be a better choice.
I bet a quick google search of "YJ with 4BT and NV-4500" or the like would get you tons of info and videos to watch.
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[QUOTE=oliver foster;3365084]The NV-5600 is at least 6 inches longer and about 200+ heavier.
I would say installing a HUGE, LONG transmission like a NV-5600 in a YJ would be a really bad choice.
The 6 speed is a slower shifting transmission that has gear spacing that is best suited to HEAVY towing, which you will not be doing with that YJ.
It is also so long your rear driveshaft will be super short and have terrible drive line angles.
That gave me exactly what I wanted and could not find. Thank you. The NV4500 from a Dodge not a Chevy is the correct fitment, ( input shaft length) I just wanted another driving around town gear which is why the 5600 sounded appealing.
The motor will make 260 HP and about 360 ft. lbs. of torque, so, the tranny, transfer case upgrade is necessary. I run a 15.5" driveshaft. Ideally I want to stay close to that length and I have the latitude to move the engine girwsrd in the bay and still have room for the cooling system.
That 5600 would have shot that to hell. Thank you very much!
I would say installing a HUGE, LONG transmission like a NV-5600 in a YJ would be a really bad choice.
The 6 speed is a slower shifting transmission that has gear spacing that is best suited to HEAVY towing, which you will not be doing with that YJ.
It is also so long your rear driveshaft will be super short and have terrible drive line angles.
That gave me exactly what I wanted and could not find. Thank you. The NV4500 from a Dodge not a Chevy is the correct fitment, ( input shaft length) I just wanted another driving around town gear which is why the 5600 sounded appealing.
The motor will make 260 HP and about 360 ft. lbs. of torque, so, the tranny, transfer case upgrade is necessary. I run a 15.5" driveshaft. Ideally I want to stay close to that length and I have the latitude to move the engine girwsrd in the bay and still have room for the cooling system.
That 5600 would have shot that to hell. Thank you very much!
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Joined: Dec 2008
Posts: 7,300
Likes: 2,887
From: vermont
[QUOTE=YJeep;3365085]
Standard misconception is that the 6 speed gives you an "extra driving around town gear" as you put it. It does NOT.
The 5 speeds, 4 gears is 1:1 with one overdrive gear, 5 TH.
The 6 speeds, 5 gear is 1:1 with one over drive gear which is 6th.
The 6 speed OD ratio is almost the same as the NV-4500.
Going up one size tire would get you a lower final drive RPM than swapping a 5 speed to a 6 speed.
Yes you want a DODGE DIESEL specific NV-4500 if you want your swap to be easy.
Welcome to DTR and keep us posted, with your project.
The NV-5600 is at least 6 inches longer and about 200+ heavier.
I would say installing a HUGE, LONG transmission like a NV-5600 in a YJ would be a really bad choice.
The 6 speed is a slower shifting transmission that has gear spacing that is best suited to HEAVY towing, which you will not be doing with that YJ.
It is also so long your rear driveshaft will be super short and have terrible drive line angles.
That gave me exactly what I wanted and could not find. Thank you. The NV4500 from a Dodge not a Chevy is the correct fitment, ( input shaft length) I just wanted another driving around town gear which is why the 5600 sounded appealing.
The motor will make 260 HP and about 360 ft. lbs. of torque, so, the tranny, transfer case upgrade is necessary. I run a 15.5" driveshaft. Ideally I want to stay close to that length and I have the latitude to move the engine girwsrd in the bay and still have room for the cooling system.
That 5600 would have shot that to hell. Thank you very much!
I would say installing a HUGE, LONG transmission like a NV-5600 in a YJ would be a really bad choice.
The 6 speed is a slower shifting transmission that has gear spacing that is best suited to HEAVY towing, which you will not be doing with that YJ.
It is also so long your rear driveshaft will be super short and have terrible drive line angles.
That gave me exactly what I wanted and could not find. Thank you. The NV4500 from a Dodge not a Chevy is the correct fitment, ( input shaft length) I just wanted another driving around town gear which is why the 5600 sounded appealing.
The motor will make 260 HP and about 360 ft. lbs. of torque, so, the tranny, transfer case upgrade is necessary. I run a 15.5" driveshaft. Ideally I want to stay close to that length and I have the latitude to move the engine girwsrd in the bay and still have room for the cooling system.
That 5600 would have shot that to hell. Thank you very much!
Standard misconception is that the 6 speed gives you an "extra driving around town gear" as you put it. It does NOT.
The 5 speeds, 4 gears is 1:1 with one overdrive gear, 5 TH.
The 6 speeds, 5 gear is 1:1 with one over drive gear which is 6th.
The 6 speed OD ratio is almost the same as the NV-4500.
Going up one size tire would get you a lower final drive RPM than swapping a 5 speed to a 6 speed.
Yes you want a DODGE DIESEL specific NV-4500 if you want your swap to be easy.
Welcome to DTR and keep us posted, with your project.
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Registered User
Joined: Oct 2019
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[QUOTE=oliver foster;3365086]
Standard misconception is that the 6 speed gives you an "extra driving around town gear" as you put it. It does NOT.
The 5 speeds, 4 gears is 1:1 with one overdrive gear, 5 TH.
The 6 speeds, 5 gear is 1:1 with one over drive gear which is 6th.
The 6 speed OD ratio is almost the same as the NV-4500.
Going up one size tire would get you a lower final drive RPM than swapping a 5 speed to a 6 speed.
Yes you want a DODGE DIESEL specific NV-4500 if you want your swap to be easy.
Welcome to DTR and keep us posted, with your project.
Big help there too. I'm currently running 3:55 gears on 33" tires. I'm not changing gearing until after engine, tranny are done and I have road tested. My target gearing is 4:10, 4:27 or 4:56. The 4BT will be governed at 2200 ( (no need to take off the governor). So, where's that leave me? Well at 2200 RPM on 4:56 gears that takes me to 70mph. Which, if you've ever spent time in a Jeep is plenty. No need for more speed. Add the 5.5-1 refuction of low inna NV4500, and a 4-1 reduction of an NP205 that gives me some good rock crawl gears with great readability.
I run 80% road, 20% off road. The 4BT gives me torque, and much needed mpg over the factory 6. 500 miles on a tank of fuel eliminated the need for the unsafe Jerry cans.
I will be posting as I go so you can see the method to the madness.
Thank you again.
Standard misconception is that the 6 speed gives you an "extra driving around town gear" as you put it. It does NOT.
The 5 speeds, 4 gears is 1:1 with one overdrive gear, 5 TH.
The 6 speeds, 5 gear is 1:1 with one over drive gear which is 6th.
The 6 speed OD ratio is almost the same as the NV-4500.
Going up one size tire would get you a lower final drive RPM than swapping a 5 speed to a 6 speed.
Yes you want a DODGE DIESEL specific NV-4500 if you want your swap to be easy.
Welcome to DTR and keep us posted, with your project.
I run 80% road, 20% off road. The 4BT gives me torque, and much needed mpg over the factory 6. 500 miles on a tank of fuel eliminated the need for the unsafe Jerry cans.
I will be posting as I go so you can see the method to the madness.
Thank you again.
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From: Richmond, VA
You want 70mph to be at around 1800 rpm, not up against the governor. You will probably be quite happy with your 3:55 axles & 33 tires and a .75 overdrive if you spend 80% of your time on-road.
I would strongly recommend using the Lord type engine mounts for your swap, too. Only having two power pulses per revolution causes a LOT of vibration no matter what you do.
It will be a fun project!
I would strongly recommend using the Lord type engine mounts for your swap, too. Only having two power pulses per revolution causes a LOT of vibration no matter what you do.
It will be a fun project!
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