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Discussion Starter #1
Hi,

I have jumped into a couple other threads that were related to what I was doing, but I guess its time to start a new thread for my project. I called it 4bt Durango #2 because of the other Durango project. For those who haven't seen my other posts, here are the details:

4bt from a Chevy bread truck, which I haven't seen (should be coming home Friday)
Dodge gas version NV4500 (so it will bolt up to my Durango t-case), and a Cummins input shaft.
Clutch is Napa Dodge Cummins, new replacement, including flywheel and all bolts
Hydraulic system will be Dakota pedal assembly, Dakota master cylinder, going to Ram slave cylinder.
Durango NP231HD t-case, which was behind the 5.9 motor.
Front suspension will be stock, so the oil pan will be heavily modified.

This will be my wife's daily driver, and our lighter duty tow rig (I have a '96 Ram Cummins for heavier loads) so it will be a study of economy and comfort,. meaning it must be as smooth and quiet as possible. She has driven my Ram enough to know what a diesel is like, but I'll do my best to make this a nice vehicle for her.

Now for my newest questions. For those who have installed the 4bt into later vehicles (such as the Grand Cherokee, Durango, and other late model vehicles), what is the best way to keep my gauges working properly? I'm assuming I'll have to keep the PCM to read the speed and transfer the signal to the gauge cluster, and the same goes for oil pressure, temp., etc., since the gauge cluster only receives a computer signal from the PCM, not individual signals from the sensors like older vehicles.

For the tach, I think one of the tach adapters from Dakota Digital might work. They are made for diesels, and I should be able to adapt the signal from their sensor to the Durango's tach somehow. If not, I could eliminate the Durango tach and install an aftermarket tach. Any thoughts?

I already have EGT and boost gauges, and will be getting a fuel pressure gauge before the project is finished.

I'll have more questions as the project begins this weekend, when I pull the motor from the van.

Jim
 

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One quick question Jim, what is the napa flywheel part number that you intend on using?
 

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Discussion Starter #3
NNCMU701191SK

I know its not a heavy duty set, but this isn't a heavy vehicle, and won't see the kind of use a 1-ton 6b would see. I also don't want a stiff pedal, since its my wife's vehicle.

Jim
 

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Discussion Starter #4
Woohoo!!!!! My 4bt is home, and it runs GREAT! I ended up going down with my father's '06 Duracrap and his friend's 20 foot trailer. The Frito truck's front bumper was 6" or so over the front of the deck, and the back of the truck was close to 3' behind the back of the deck! It did tow great though, although that piece of crap Duramax only got 7 mpg on the way home!!! (trip down with an empty trailer was only around 12 mpg!) We got down there and the rain started (which is the reason I took the trailer instead of riding my bike down) so loading it was fun. It started right up and ran great, only a very slight puff of smoke when it first fired. After it warmed up I drove it onto the trailer (man, it barely fit between the fenders!) and we headed for home.

Because of the rain I haven't been able to find out much about it, except that the truck is in very good condition and all I was able to read off the tag is that its a 120hp version. Its still sitting on the trailer, but hopefully tomorrow will be drier and I'll be able to unload it, test drive it, and read the rest of the engine plate. Pics will be coming when its dry enough for the camera.

My initial thought of scrapping the truck is almost gone. I think because of the condition, I'll drop a good running 350 in it and sell it complete.

Jim
 

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My initial thought of scrapping the truck is almost gone. I think because of the condition, I'll drop a good running 350 in it and sell it complete.

Jim
I've come to the same conclusion, too. It's always been hard for me to junk good stuff.
 

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I've come to the same conclusion, too. It's always been hard for me to junk good stuff.
Nice to hear these comments. If you buy the P30 at the right price you can drop in a V8 gas or diesel and end up getting your 4BT for almost free if you don't count the labor.
 

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Discussion Starter #8
The truck pulled it great, but luck was on my side. The pickup is a quad cab '06 Chevy 3500 dually, so the wheelbase sure helped. The weather was also on my side. Although it was raining the whole way back, it wasn't windy. If the wind picked up, I'm sure it could have gotten scary quick. We were able to cruise at 65-70 with no issue.

More good news on the van. I had a few minutes to look it over tonight after dinner when the rain let up some, and found that the frame is in new condition- no rust like I'm used to up here. While looking under it, I noticed that it has been greased VERY recently- the little dabs of grease at all the fittings don't even have dust in it, so I'm fairly certain it hasn't been off the road long. My eyes picked up something else- the driveshaft U-joints are all new. Following the shaft up, I found that the transmission has NO dirt or grime on it...and a tag on the side of it (I wasn't able to get under and read it), and the aluminum looks new. I'm pretty sure this is a fresh transmission!

Good call on the thought of another diesel...I can get 6.2s a dime a dozen around here, so a couple hundred bucks should get me a good runner for resale. I really hate to chop up something this good, and even using it as a storage shed, although tempting, would be a waste of it. Oh well, the main thing is to get this engine out so I can start prepping it for the Durango.

Jim
 

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Discussion Starter #9
O.K., I need some input to help me make a decision. For those who have worked on Dakotas/Durangos, you know about the front differential issue. The front diff assembly is bolted to the engine block, trans bellhousing, and engine mounts and is hung from the motor mounts with the engine. When the 4bt goes in, there is no simple way to bolt up the front diff. I have come up with a few possible methods of dealing with this.

-Make brackets to attach the 4bt to the existing Dodge motor mounts and diff, and hang it all just like the 360.

-Make brackets to attach the front diff to the 4bt and bellhousing and mount the entire assembly to the Durango frame with the bread truck motor mounts (I like this idea)

-Leave the diff hanging from the frame by the existing mounts, build a rear mount for the diff where it would have bolted to the bellhousing, then mount the 4bt independently of the diff assembly. This seems overcomplicated, and would require more room between the diff and engine to allow for movement, and I would have very little room as it is. I really don't like this idea, but threw it out anyway.

I guess the big question is, how would the front diff like the vibration of the 4bt, and would the additional weight of having the diff hanging from the engine cause the bread truck mounts to transfer more vibration? My theory is that having the extra weight of the diff bolted to the engine should reduce vibrations (if anything), so I think I should be safe.

By the way, this engine seems to be VERY smooth, quite quiet, and barely vibrates. Its almost as smooth at idle as the 360 in the Durango. I test drove the bread truck today for several miles and the engine seems very strong.

Jim
 

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By the way, this engine seems to be VERY smooth, quite quiet, and barely vibrates. Its almost as smooth at idle as the 360 in the Durango. I test drove the bread truck today for several miles and the engine seems very strong.

Jim
There's something wrong with it for sure :dustin:

Certainly doesn't sound like the 4bt that I know.

I don't have any real answers for your front axle questions, i guess that's obvious since I ditched mine... How do you plan on clearing it? trimming the oil pan until it fits?
 

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Woohoo!!!!! My 4bt is home, and it runs GREAT! I ended up going down with my father's '06 Duracrap and his friend's 20 foot trailer. The Frito truck's front bumper was 6" or so over the front of the deck, and the back of the truck was close to 3' behind the back of the deck! It did tow great though, although that piece of crap Duramax only got 7 mpg on the way home!!! (trip down with an empty trailer was only around 12 mpg!) We got down there and the rain started (which is the reason I took the trailer instead of riding my bike down) so loading it was fun. It started right up and ran great, only a very slight puff of smoke when it first fired. After it warmed up I drove it onto the trailer (man, it barely fit between the fenders!) and we headed for home.

Because of the rain I haven't been able to find out much about it, except that the truck is in very good condition and all I was able to read off the tag is that its a 120hp version. Its still sitting on the trailer, but hopefully tomorrow will be drier and I'll be able to unload it, test drive it, and read the rest of the engine plate. Pics will be coming when its dry enough for the camera.

My initial thought of scrapping the truck is almost gone. I think because of the condition, I'll drop a good running 350 in it and sell it complete.

Jim
I resent those negative Duramax comments :p . You know wind resistance is this biggest mileage killer next to a heavy foot. 12mpg seems a bit low unloaded - how heavy is that 20' trailer? The truck is probably around 7-7.5K#
 

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Discussion Starter #12
I don't have any real answers for your front axle questions, i guess that's obvious since I ditched mine... How do you plan on clearing it? trimming the oil pan until it fits?
Yup, lots of trimming. I have room to lower the diff around 1", and I'll trim the pan until it fits. There will be room on the passenger side to add a section to increase the fluid capacity back to stock. I have a feeling about the only thing I'll bee keeping off the 4bt pan is the mounting flange area and about 1" or so down. Its all just guessing for now, until I can get the engine dropped into place so I can take measurements.

I was checking under a Dakota here at work this morning, and was thinking about the front diff/engine mounting ideas. Does anyone have any idea how the 4bt would do with the factory Dodge rubber mounts? It looks like it would be very easy (relatively speaking) to adapt the 4bt onto the Dodge rubber mounts and diff brackets.

Jim
 

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Yup, lots of trimming. I have room to lower the diff around 1", and I'll trim the pan until it fits. There will be room on the passenger side to add a section to increase the fluid capacity back to stock. I have a feeling about the only thing I'll bee keeping off the 4bt pan is the mounting flange area and about 1" or so down. Its all just guessing for now, until I can get the engine dropped into place so I can take measurements.

I was checking under a Dakota here at work this morning, and was thinking about the front diff/engine mounting ideas. Does anyone have any idea how the 4bt would do with the factory Dodge rubber mounts? It looks like it would be very easy (relatively speaking) to adapt the 4bt onto the Dodge rubber mounts and diff brackets.

Jim
My guess is that it would destroy them prematurely. If you don't mind replacing them every so often, it'd be worth a shot I think. They are a pretty big piece, not sure how pricy they are. mine are in the scrap pile if you want me to try and dig them out for you. they were still in usable shape, though not new.
 

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I am very intrested in the solution you find for the mounting brackets. My 89 Dakota will be getting the 4bt treatment in the near future. I am considering the dry sump route, but I have not picked up my cummins yet to start modifying.
 

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Discussion Starter #15
Woohoo!!! The engine is out of the van. Kind of disappointing in one way, because now I can't start it and drive it. But its one small step closer to the Durango. Removal wasn't too bad, it came out the side door. Hopefully tonight I can drain the oil and start cleaning/degreasing it, and start on changing parts around. I have a Dodge intake plate with the grid heater, which will be replacing the aftercooler. I'm planning to use an intercooler once I get the engine in place and can get some measurements and plan exactly how it will be positioned.

Thanks Diesel Durango. I really didn't think the Dodge mounts would be a good idea, but I was hoping. I'll go with the original plan of using the bread truck mounts and attaching the diff to the block. I'm glad you have been through most of this before me (with the exception of the diff), so I have someone to bounce ideas off from. And its nice having someone who has made any mistakes before me, so it saves me from them :beer:

Jim
 

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Discussion Starter #16
Here are the first pics of the engine. I removed the aftercooler and cut down the Dodge intake plate (shown). I also got the turbo, alternator, pulleys, and oil pan off. I test fit the flywheel, and ordered the Dodge adapters. I was going to use the adapter off my Ram, but for the cost of the adapters, I just bought one instead. The adapter plate was $75, and $50 more for the bellhousing and release arm. They should arrive early next week. While I wait I'm cleaning and prepping the engine. Hopefully all the parts will be here by next weekend and I can pull the 5.9 out of the Durango, yank the nose off, and test fit the 3.9.

I'm a little concerned about the A/C compressor placement. I was planning to use Dodge Cummins brackets, but they put the compressor too low, where it will hit the frame rail. Even my Ram has the frame dimpled to clear it, so it will never work in the Durango. I may be able to mount it high, maybe put the alternator a bit lower than the original 4bt bracket and put the compressor above it. I think I will still get decent belt engagement that way, especially considering how wide the belt is.

Jim
 

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Discussion Starter #17
I have been doing some numbers crunching, and this is where I'm at: I have $3941.92 invested in this project as of right now, with most of the major parts bought. I still have minor stuff left. I also have an estimated $2300+ coming back when I sell off the extra parts and the step van. That will put the project around $1700. Hopefully I can finish it for between $2000 and $2500 when I'm done.

$2001 Motor (P30 van)
$630 NV4500 4x4 version
$465 Dodge Cummins clutch/flywheel, Napa Item#: NNCMU701191SK
$100 Pedal assembly, Dakota clutch master cylinder, Dakota clutch line, Dakota clutch slave cylinder
? Intercooler
? Dynamat or similar
? Intercooler tubing
$100 Dodge Cummins Input shaft & retainer
? Engine paint DE 1638 Cummins Beige
$122.50 Boost & Pyrometer gauges, Isspro (ebay)
? Fuel pressure gauge
? 3200 governor spring
$75 Dodge flywheel housing
$50 Dodge bellhousing
$15.49 Gauge pod
? Shifter boot
? Shift lever
$250.50 Dodge Cummins power steering pump, Dodge Cummins vacuum pump
$132.43 Dodge starter, grid heater assembly, grid heater relays

Parts sold/to sell:
$300 (as of today) Chevy adapter parts (on ebay, still climbing!)
$2000+ (estimated) P30 selling price, based on lowest prices I have seen them for around here with gas engines.
? Durango 46re transmission
? Durango 5.9 engine parts (injectors, throttle body, distributor, etc.)
 

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where did you get the dakota pedal assembly? I can't find it as an option on car-part.com and i don't have all day to call salvage yards, most don't seem to respond to email.

Do you have ideas of where to put the intercooler? It is pretty cramped unless you move the radiator, or mount the intercooler behind the radiator. I have all the 6bt parts to put an intercooler in sitting here, but am not sure how to do it (or if it's worth it necessarily)
 

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Discussion Starter #19
I have no plans yet for the intercooler. I'll play it by ear when I get the engine in place...which is happening this weekend. Please give me your opinion on this- I'm planning to keep the transfer case in the stock location, put the transmission crossmember wherever I have to for the NV4500, and let that decide the engine position. Hopefully that will work out. Then I'll see if I have room to move the radiator back a couple inches, and put the intercooler in front of it. I have looked at some of the intercooler sizes, and I'll choose which one I go with after I see how much room I have to work with.

For the pedals, I got lucky- I used car-parts.com and looked for any yards with a Dakota with manual transmission, and I found that our local one had a 5-speed for a '97 Dakota listed (3.9 I think), so i called about the pedals. I ended up with the pedals, master, and slave for $100. I'll probably put new master and slave in at some point, but these will be perfect for testing and to use for a while.

I just received the Dodge Cummins bellhousing and adapter today, and they look great. I can't wait for tomorrow night to get here, so I can start pulling apart the Durango.

Jim
 

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That sounds like an interesting placement idea to me. I think it could work. I would try and bolt it all together, make sure you have enough cowl/firewall clearance. the closer you get, the higher the chances of down pipe interference. i have the GM drop manifold and i have like 3/4" between the down pipe and the firewall, that's with a stock P30 down pipe, custom wouldn't be a problem. The further forward you go, the more sump you will have to modify. Mine doesn't have much room to move in any direction and the back valve cover is right at the edge of the cowl, i had to bend the cowl so that they didn't touch.
 
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