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First I would like to say hi. I've been lurking here for a while, but this is my first post. I've been thinking about putting a 4bt in my 99' jeep grand cherokee. I'm wondering how the dodge 45rfe would stand up to a 4bt, and how much power it is rated for. I know it is used behind a lot of the full size ram trucks with gas engines, but I haven't found anything about the power ratings.

Brian
 

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Welcome. I have done a little research by accident on this topic. I put one in a Durango and have gone through the diagrams for my 46re pretty thoroughly. What i can say is there is A LOT more to the electronics of the 545rfe than the 46re. Compared to the 46RE it is a very electronically complex transmission. I would not even attempt to swap something like that. It may or may not work, but it looked like a lot of work to me.

I wasn't directly looking at the 545rfe so there may be something about them that would make it possible, but this was just my observation.

They do have a seperate computer for the trans, but i'm not sure exactly what it means.

I would get a factory service manual and start reading up on them. I know they are a pretty reliable transmissions behind gas engines, but that's about all i can tell you.

good luck.
 

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Discussion Starter · #3 ·
I know the electronic are controlled by a seperate computer. There is a controller available that works like the compushift for the 4L80E to make it a stand alone unit, allows you to change your shift points as well. I trying to figure out if it would be reliable enough to handle the torque. It's just one option, but retaining the stock tranny could make a few things easier.

Brian
 

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First I would like to say hi. I've been lurking here for a while, but this is my first post. I've been thinking about putting a 4bt in my 99' jeep grand cherokee. I'm wondering how the dodge 45rfe would stand up to a 4bt, and how much power it is rated for. I know it is used behind a lot of the full size ram trucks with gas engines, but I haven't found anything about the power ratings.

Brian
Bell pattern and electronics = a ton of money in a custom adapter and a controller, I personally would use a proven diesel transmission, they are readily available. Just my .02 cents...
 

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Bell pattern and electronics = a ton of money in a custom adapter and a controller, I personally would use a proven diesel transmission, they are readily available. Just my .02 cents...
which proven diesel automatic with overdrive would you use that doesn't require at least a lot of money in electronics? The only one that I can think of is the 700r4, but i would hardly call it proven.

If you don't plan on towing or turning up the 4BT, I would probably use the 700r4 though. Mine seems to handle it without any issues, though i don't yet have a thousand miles on it. My lockup is a bit annoying too at low speeds, it seems to keep the converter locked down to like 30mph, which is about 800rpms , try and accelerate in .70 OD then...

If the controller isn't outrageously priced, I would probably try and run the 545rfe first, as long as you can figure out how to bolt it up to the 4bt. I have no clue what pattern the 4.7 is...but it is probably not a readily available adapter.
 

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which proven diesel automatic with overdrive would you use that doesn't require at least a lot of money in electronics? The only one that I can think of is the 700r4, but i would hardly call it proven.

If you don't plan on towing or turning up the 4BT, I would probably use the 700r4 though. Mine seems to handle it without any issues, though i don't yet have a thousand miles on it. My lockup is a bit annoying too at low speeds, it seems to keep the converter locked down to like 30mph, which is about 800rpms , try and accelerate in .70 OD then...

If the controller isn't outrageously priced, I would probably try and run the 545rfe first, as long as you can figure out how to bolt it up to the 4bt. I have no clue what pattern the 4.7 is...but it is probably not a readily available adapter.
I would use any transmission that was manufactured behind a diesel before I would adapt something like this. A lot of people think they would be saving money trying to use components they already have that are working fine for them now. I suppose they want to save money and time chasing parts. My opinion is it will cost more in the long run trying to re-invent the thing.

To clarify here also, I would use any transmission that was manufactured behind a diesel and I would be certain to address the known issues that are common and often overlooked and give many of these transmissions their bad reputations.
 

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So will a HD dodge auto trans bolt into the stock location on 1500 series truck? (2nd gen)

I would like to keep my conversion as simple as possible, but I do plan on turning up the power on the 4BT, to about 250hp at the wheel.

The transmission choice is going to be the part I know the least about, especially when it comes to which ones have more computer control, etc.
 

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So will a HD dodge auto trans bolt into the stock location on 1500 series truck? (2nd gen)

I would like to keep my conversion as simple as possible, but I do plan on turning up the power on the 4BT, to about 250hp at the wheel.

The transmission choice is going to be the part I know the least about, especially when it comes to which ones have more computer control, etc.
trying to just bolt anything into a stock location is looking for a lot of frustration. You are better off getting one that will FIT in the stock location and build your own mounts.

I'm not sure what it would take to get a 47re to work with the 4bt, might be easy for all i know...
 

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which proven diesel automatic with overdrive would you use that doesn't require at least a lot of money in electronics? The only one that I can think of is the 700r4, but i would hardly call it proven.

If you don't plan on towing or turning up the 4BT, I would probably use the 700r4 though. Mine seems to handle it without any issues, though i don't yet have a thousand miles on it. My lockup is a bit annoying too at low speeds, it seems to keep the converter locked down to like 30mph, which is about 800rpms , try and accelerate in .70 OD then...

If the controller isn't outrageously priced, I would probably try and run the 545rfe first, as long as you can figure out how to bolt it up to the 4bt. I have no clue what pattern the 4.7 is...but it is probably not a readily available adapter.
The 46RH is a very proven tranny when a BD or other T/C maker is used. It's a TF727 front half with a O/D back half on it. The best thing is it uses NO computers and it comes stock in the Dodge Diesel trucks. If your lucky enough to find it still in the truck, you can get the mounting plate off of the back of the motor. Then all you do is bolt it all together and build a custom crossmember. The thing to remember is, K.I.S.S., Keep It Simple Stupid. By that I mean it's easier to build a crossmember, which anyone can do in their garage, than to buy or have built an adapter.

I know this due to the fact I'm using the same tranny in my 1988 Jeep Wagoneer 4BT swap. Hope my loose change on the matter helps.:beer:
 

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I used a 47rh behind a 6bt

in my Suburban. It is longer than a 47re beacuase the overdrive section is longer. However this tranny can be made completely standalone and includes lockup and overdrive. If you find or decide to do one I will be happy to explain how I wired overdrive to come on at 46 mph and lockup at 54. Plus even with heavy mods the tranny even in stock form can handle a lot of abuse, and many have been built to take some serous 6bt power clear up to 900+ horsepower.

Currently I am looking for a tranny for my Scout conversion. The ultimate would be an NV4500, but since I have a Ford bell housing a ZF tranny would suit me fine. I have been studying the forum and reading about trannies and I still feel like I am missing info. I know an NV4500 would be great, and a ZF sounds promising but it doesn't seem like much else has been discussed in detail. Or at least to my satisfaction. I am curious about the Durango tranny, I think they were strong but I am wondering in an automatic are people keeping the gas torque convertor? Love the discussion, I hope someone chimes in with more knowledge.
 

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in my Suburban. It is longer than a 47re beacuase the overdrive section is longer. However this tranny can be made completely standalone and includes lockup and overdrive. If you find or decide to do one I will be happy to explain how I wired overdrive to come on at 46 mph and lockup at 54. Plus even with heavy mods the tranny even in stock form can handle a lot of abuse, and many have been built to take some serous 6bt power clear up to 900+ horsepower.

Currently I am looking for a tranny for my Scout conversion. The ultimate would be an NV4500, but since I have a Ford bell housing a ZF tranny would suit me fine. I have been studying the forum and reading about trannies and I still feel like I am missing info. I know an NV4500 would be great, and a ZF sounds promising but it doesn't seem like much else has been discussed in detail. Or at least to my satisfaction. I am curious about the Durango tranny, I think they were strong but I am wondering in an automatic are people keeping the gas torque convertor? Love the discussion, I hope someone chimes in with more knowledge.
the gas torque converter is going to be a really high stall, like 1800? compared to the 2500/3200 rpm governor, this doesn't seem like a good recipe. The magic number is supposedly a 1000rpm stall. I have no clue how this performs and to my knowledge no one has any first hand experience just yet... I am using a stock stall diesel converter with my 700r4 and it seems to drive just fine, but maybe 1000 would be better? mine is rated at 1200-1400 rpms.

what kind of info on the manuals are you looking for?? I would keep reading, it seems like there is a TON of information regarding the ZF and NV transmissions. The mazda transmissions are reportedly good as well...
 

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re.545RFE

The 545RFE was used in 2005/2006 jeep liberty diesels and has weak points which the aftermarket stepped up and offered a TC and shift kits...so its a proven design. Problem:where is get an adapter???

Jason
 

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The RFE doesn't need an adapter. I have one that I swapped into my Dakota (along with the 5.7 Hemi) and it uses the same BH pattern as all of the other common Dodge transmissions. The output is also the same- 23 spline, same as many other Dodge transmissions/t-cases. Its also exactly the same length as most other autos, including the 42RH that was in my Dakota.

With that said, I have already almost drowned in wiring while building the harness for this engine/trans. I'm only able to do it because I'm keeping the package. I would never, ever try to use the RFE alone! Although some early versions used a separate controller, its VERY intertwined with the engine controller. It needs to read such items as RPM, ignition timing, and many other things to work. Its not as simple as adapting a throttle position sensor to the diesel.

The easiest thing to do would be to use one of the Dodge diesel transmissions, such as the 47RH used in the 90's (such as my '96). It is controlled by a computer for overdrive and TC lockup, but you could use the diesel computer and adapt the throttle position sensor to the 4bt. The 47RH is as much junk as the rest of the Chrysler autos, but it should hold up much better behind a 4bt than they did in my Ram (lost count of the number of transmissions, but this one was slipping with under 20k on it, installed by a dealer)

Jim
 
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