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Discussion Starter · #1 ·
Here is what I am looking at. I have a 95 chevy k2500 with a 6.5 and 4l80e.
I have come to conclusion that I just can't make enough power and stay reliable. So I want to put a 94-98 cummins in my truck. I think from what I have read that I would like to go with a 5 speed trans but how should I go about that. Do I have to go with the dodge trans and t-case or will I be able to run the t-case I have? I want to retain my IFS and I know that may cause some fabrication issues as far as motor clearance, but it can be done right? I just don't like the upshift of the 4l80 into o.d. it seems to low at about 50 mph. As far as the trans and t-case I think I have seen people run a hybrid trans with dodge front and gm rear? Do these 5speeds have hydraulic slave cyliders? Fabrication is not a problem, but I want to make sure I have everything together so that I do not run into any unexpected expenses that cause me to halt the project after things are cut and pulled apart. Thanks.
 

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You can run a stand alone controller for the 4L80E and adjust it to shift whenever you want it to.

5 speed is probably easier though. You can put a dodge input in a 96 or newer GM NV4500 and bolt it to a dodge bellhousing or you can put the chevy mainshaft and tailhousing on a dodge NV4500.
 

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I put a 6bt in a Suburban

It is a 95 and had a 6.5 to start. I sold my 4l80e and 6.5. My transfer case is a hybrid, the front of the case is a Dodge and the back is Chevy. You need to maintain the back part of your t-case because that is where your speed sensor is located. I also used a bracket to retain my GM alternator and A/C. The alternator houses your tachometer. I used a 92 motor and a 47RE tranny converted to an RH (don't ask about that). I used a pair of hobbs switches to automate overdrive and lockup. If I where doing a GM and wanted a 5 speed I think you could buy an NV4500 from behind a GM truck and then use the Dodge adapters to get hooked to the Cummins. All of my gauges work, but I haven't figured out cruise control yet.
 

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Discussion Starter · #4 ·
xyz how is the power difference from the 6.5 to the cummins? How about the mileage difference? Some guys w/ 6.5's get 17-18 I get about 13? I want more power but I also am looking to get some mileage and have a little reliability. Is yours still IFS or did you straight axle yours?
 

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I kept the IFS

I just cranked up the torsion bars. As far as mileage it is better, especially if I keep it under 2000 RPMs. My truck has 4.10's which it doesn't need now and it can tow in OD no problems and goes straight up hills without slowing down. My Cummins pumps settings are stock and I had New Era custom cut some injectors with a narrow spray pattern for veggie but nothing much hotter than stock. My Cummins has more power than my 6.5 had with all the Heath upgrades, straight pipe and K&N filter. The truck starts easier and the Cummins runs with a bump of the key. The 6.5 had on and off days. My 4l80e that was behind the 6.5 was mildly built and at 20,000 miles it was starting to slip. The 47RH is a lot more solid. Maybe I can get you some pics.
 

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Discussion Starter · #6 ·
Pics would be great. I think I am just going to try to find the motor and 5speed then try to sell the 6.5 and 4l80. With the price of used 6.5's I hope top recoup some of my spent money to build this. How did you wire your heater grid? Can I jsut use my glow plug controller to run it or do I need to operate it manually? I read somewhere that it is not used above 40 deg. anyway? Not sure about that one but I know I read it somewhere.
 

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my thoughts are that you look for a whole rig for parts . i bought a 91 dodge 6bt stick four wheel drive that had been wrecked for 2000k all the wiring is there plus the fuel tank rear ends transfer case etc.
 

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Discussion Starter · #8 ·
I do want to find a wrecked complete truck so that I have most of what I need. However, I need to know how to operate these parts. For example the heater grid. My glow plug controller will work with my ecm and temp switch but the glow controller in cold weather is only on for 15 seconds then cycles 2 or 3 more times after startup but only for a couple seconds. Is that going to be enough or do I need to operate it manually? I would like to retain the stock ecm and use it so all of my gauges work. I know that I will have to either pull my Check engine light or fool the ecm so that it does not set a code. Just don't want a light in my face all the time. I would also need to find a GM NV4500 to get the rear section of that trans. That is assuming that my tcase will mount up to that tranny?
 

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The ecm has nothing to do with the gauges as mentioned before. Tach runs off the alternator water temp and oil are two wires in the engine harness.

If you have a 92-95 GM NV4500 it's a boat anchor for what you're doing, If you have anything else all the parts interchange.
 

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Discussion Starter · #10 ·
Okay so the gauges are seperate of the ecm. The temp switch that relays to the computer coolant temp is separate of the temp sender for the gauge. This is what gives the amount of glow time or heater grid time as the case will be. If I need more time and have to manually operate this then I will, but if not I would like to have it controlled by the ecm.
 

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Discussion Starter · #11 ·
Another question. I am still trying to get an idea of what to use and how to make this as painless as possible. If I wanted to use a auto trans which would be the best to go with? Is there a purely mechanical dodge auto that will hold up to the power? If not do you guys tap into the trucks existing harness or take the entire wiring harness from the donor truck? I would like the idea of keeping a over drive auto but how much of a hastle is it going to be to control lock up and get my speed ometer to work? Also what side is the output for the front axle on the transfer case. I really want to have this go as smoothly as possible and have all my ducks in row before I start it. I know that I have alot of questions but I really want to do this.
 

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If you need it I have the whole clutch pedal assembly for a NV4500 out of a 95, it will fit yours, and the master/slave cylinders. As well as the bell housing, I put the nv4500 in my 72 Dually, it required going to an Advance Adapters kit so I could use my manual clutch pedal.
 

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Hey wireman_67, I am doing the exact same swap you are, I have just recently acquired a 94 Dodge CTD that will be finding a new home into a '95 Chevy K2500 that had 6.5 and a 4l80E in it. I too am keeping the IFS and I plan on using a 47RH trans. The donor Dodge i have is unfortunately a 2wd truck so I will have to find a solution to that. Does anyone know if there is such a thing as a conversion kit for a 2wd to a 4wd trans? how about an adapter so i can retain the chevy transfer case?
 

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2Wd/4Wd adapter

Budweiser360, I think all you need to do is get a 4wd tail housing for your 47rh trans. Only 5 of the 6 holes will line up with the chev transfer case, but that`s enough. You`ll also need to get a dodge input gear (23 or 29 spline to match the trans out put shaft) put in the chev transfer case. The easy fix for o/d & loc-up is found @ transmissioncenter.net. look in the dodge section under 518 lock-up fix. Hope this helps.:idea:
 

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Crewcab59 sells the motor mounts that use the stock Gm frame mounts and will clear the IFS 4x4 diff. saves a lot of time not havin` to reinvent the wheel. bounce
 
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