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I have been researching about the 4bt engine i had people tell different thing but i want to know for sure its true. number one the tranny issue I have very well built 47re. will it fit the 4bt i have heard that 4bt and 6bt is the same and what else i might need to get started like mounts etc... number two gearing I have 3.55 with 35 in tires would that be good enough. number three can you use the same ideas to get power like the 6bt?
 

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Using the dodge/cummins engine mounts it should bolt in!!!
You will need the engine/belhousing plate that Dodge uses . It bolts to the back of the block. The rest is all about the wiring up it needs. Keep the computer for the correct trans shifting and lock-up.
30 mpg are in reach!!
 

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Isn't the 47RE bell housing bolt pattern different between the gasoline & diesel versions?
 

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The bolt pattern is the same between gas & diesel (at least for Gen IIs). But the depth of the bellhousing is different. Find out if the depth of a gas 47re is the same as the 47rh's used in the diesel trucks.

For the 47RE, I'd skip the electrical nightmares and find a diesel 47RH that is much easier to deal with. Only thing electronic there is the lockup TC and overdrive, both easily handled with switches. Don't forget that the gas tranny will have different shift points than the diesel version. Bolt your trans up to a 4bt and you'll never shift at high throttle. The trans is ready to run up to 4500+ RPMs, and you'll never get there. You'll need reprogramming to handle it.

Next up is the torque converter. You'll need a torque converter from a diesel, otherwise you'll never make use of the 4bt's torque.

Last, Dodge has serious issues with all of their automatics, especially those behind diesels. Its all in the design. True diesel autos, such as the Allison, were designed for diesels from the ground up. Dodge uses gas transmissions modified for diesel use. The biggest issue is line pressure. Pressure builds with RPMs, and inline diesels put out too much torque at low RPMs for the transmission to handle. They work for a while, but when you are putting out gobs of torque at an RPM level where the trans can barely keep the clutches and bands locked together, you get fast wear and weak shifts after a very short time. Gas engines make more power as the RPMs come up, so as the power builds, so does the line pressure.

If it were me, I'd put the 4bt in with a 5-speed. The cost won't be any more than finding a decent auto to handle the 4bt, and may even be less. It will bolt right in, as the pedal assembly and hydraulics from a manual Ram will bolt right in. I practice what I preach- I swapped an NV4500 into my 2000 Durango when I put the 4bt in, and I would do it exactly the same way again.

Jim
 
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