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Discussion Starter #1
what kind of real world fuel mileage are you 4bt guys getting?

Im stuck between a 4 or 6cyl cummins and want to know what the differences are. What are you're mods?
 

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Umm, My 4bt gets 24 mpg in a 6500 lb truck and my 6bt gets 18-20 in a 7300 lb truck. Both have about the same mods, PODs, intercooled, intake, exhaust, pump, gov spring, blaa blaa blaa. The 6bt is a little higher geared though.

It all depends on what its going in. Which is???
 

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Discussion Starter #4
it is going in a 86 f350 4x4 reg cab with 33's and 3.55 gears. Trying to decide what tranny to use also
 

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1989 Jeep Wagoneer, 360v8, 727, stock for now,
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it is going in a 86 f350 4x4 reg cab with 33's and 3.55 gears. Trying to decide what tranny to use also
The Dodge NV4500 would do nicely. With 33's your turning about 1800 rpm at 65, that tire might be too tall depending on the load and weather or not you turn the fuel up. You can allways adjust the final overall ratio by changing the tire size up or down.
 

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that thing would be purdy kool with a 6b in it!
 

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My 6BT, Cummins Dakota gets between 18-22 all over both highway and city. I have 38" tires and im running a 4.10 gear. I have never had a problem with lack of power or gear at all.
 

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I consistently get 23-25 empty F150 4X4 3.55 and factory 15" tires. The worst I have seen loaded is 18.5. When I say loaded, 3000-7000lbs on a trailer and normally will do 20-22. I have the timing advanced and fuel turned up slightly estimated 130HP no other mods what so ever factory 105HP non intercooled. I am running the diesel ZF 5 speed not the small block and am very happy with it.

I would lean towards the 4BT but it depends what you are looking to do with the truck. I would stick with the ZF and not the NV trans, it simplifies your conversion and in the end is really no more money than an NV trans and t-case It keeps more factory parts and less custom parts.
 

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Discussion Starter #9
Hello i have a problem. i have a 1990 dodge cummins 4x4 auto(727). This drive train setup is going into a 1986 ford f350 4x4 that has a 460/c6/np208

Problem 1: Need a drivers side drop transfer case that will bolt up to the 727.First that comes to mind is nv241.

Problem 2: I want to use a np205 but the dodge and ford 205's are way different. So i though swap out the input shaft to the ford unit. well that would make the shaft way to long. and they use a wierd adapter. See where i am going with this?

Problem 3: speedometer issues. how would i make it work correctly when swapping out the cases?

here is the info site for all needs.
http://www.high-impact.net/transmiss...case_NP205.htm
 

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You can put the dodge 23 spline 205 input and cast adapter piece into a Ford mated NP205 case. The Ford mated cases are small bearing input just like the 23 spline dodge. Just have to drill the ford case for 6 out of 8 of the adapter bolts (2 of them will not go into anything).
 

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Discussion Starter #11
really?

Hmm would that work? I guess that would take car of the extra length etc. Wait no that still wouldnt work because the dodges have some way thing at the bottom of the adapter plate with 2 extra bolts for something?

I just picked up a nv241 dld from a 95 auto dodge truck that should bolt right in with no issues right?
 

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I consistently get 23-25 empty F150 4X4 3.55 and factory 15" tires. The worst I have seen loaded is 18.5. When I say loaded, 3000-7000lbs on a trailer and normally will do 20-22. I have the timing advanced and fuel turned up slightly estimated 130HP no other mods what so ever factory 105HP non intercooled. I am running the diesel ZF 5 speed not the small block and am very happy with it.

I would lean towards the 4BT but it depends what you are looking to do with the truck. I would stick with the ZF and not the NV trans, it simplifies your conversion and in the end is really no more money than an NV trans and t-case It keeps more factory parts and less custom parts.
Hello Deer Country, I've put a 4-53T Detroit in a Chevy crew cab and recently found out about this 4BT engine and am concidering putting one in a 1/2 ton Ford. My question is, how is it more simplified to use a ZF over the NV transmission? I don't know much about either except for what I have read. Were there more 4BT's used in the GM step vans than in the Ford? If so I thought there would be more parts available for GM. Maybe I'm wrong, Im just getting started. Thanks, Allen
 

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I have seen a lot more chevy chassis vans than fords but it may depend on your area more than anything. As far as simplicity in the ZF versus NV their are several things like, original crossmember, original t-case, original driveshafts, original slave cylinder. It is more expensive to build a diesel ZF plate but look at what an NV costs versus a ZF and you don't have to buy overpriced specific oil for it either. Look at the cost of a 1356 BW t-case and then price a t-case for your NV over twice the price. Then after you get a NV trans and t-case try to find a cheap bellhousing and engine plate to use along with it, the ZF already has its own bellhousing. So all of a sudden the Ford plate gets much cheaper than one realizes. If your able to find all the NV parts cheaper than you may want to go that route but you will have a lot more time into customizing it to fit your Ford truck.

Good luck on the swap what exactly are you putting it in?
 

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really?

Hmm would that work? I guess that would take car of the extra length etc. Wait no that still wouldnt work because the dodges have some way thing at the bottom of the adapter plate with 2 extra bolts for something?

I just picked up a nv241 dld from a 95 auto dodge truck that should bolt right in with no issues right?
The 727 doesn't have a rear seal like the 47RH does. Make sure you seal the joint between them.

I built a 23 spline Ford 205 last week. Do a little more homework before you deam it impossible.
 
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