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Putting a new '88 4BT in an M715 Jeep. Want to use it as a daily driver if I choose, will wheel some, will tow some. And like everyone would like to spend the least amount of cash and have the least amount of fab work needed. But I'm willing to do what is needed to do it RIGHT.

I used the search function but was not really successful (probably user error :confused: )

For those who don't know, the M715 weighs in at almost 6,000,
Has 586 gears (would like to go to 456 later)
Has an NP205 TC
Has stock 9.00x16 NDT's (about 36" tall)

Thanks,
Jeff
 

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I really like the 4l80e. The only problem is that the stand alone computer its costly ( i am a college student with no one so in other words every thing is costly).
 

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The 47RH is the simplest to get working right, very simple wiring. The 47RH has more aftermarket support for a diesel, but the 4L80E is a better transmission in stock form. The dodge adapters are dirt cheap and they aren't tilted.
 

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I like my 4L80 manual shift if you dont mind rowing a shifter. I would rather that than an aftermarket controller that half way works. Added bonus is that it is cheaper to build.
 

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I used the A518 trans that was bolted to the 5.9 cummins so I figured that it would handle the 3.9 with no problem.
thats the same one I'm using for my 4BT swap:D
 

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someone was saying that the 47RH are pretty long. I was wondering if I have enough room on a 107" wheelbase to have you comfortably?(FJ60)

I know you can shorten the drive shaft, just was wondering if there was going to be enough room for stress free movement. I plan on doing a SOA also so I dont want to have any high angles if I can avoid it.

Thanks
 

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If you want the cheapest get the 47RH. If you want the best get an Allison.
 

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Is the allison a hard install?

I was thinking it was and it required a control unit. I am probably wrong but was just thinking that was the case. And when it comes down to it what does the allison have that the Dodge would not?

If the allison doesn't do anything special that I cant warrant the price. It is my understanding that with a little billet help the 47RH is a very very capable tranny for any 4BT ideas I have.

What about the weight....is the Allison lighter?

I thought it was alot heavier but once again I have NO IDEA.
 

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Is the allison a hard install?

I was thinking it was and it required a control unit. I am probably wrong but was just thinking that was the case. And when it comes down to it what does the allison have that the Dodge would not?

If the allison doesn't do anything special that I cant warrant the price. It is my understanding that with a little billet help the 47RH is a very very capable tranny for any 4BT ideas I have.

What about the weight....is the Allison lighter?

I thought it was alot heavier but once again I have NO IDEA.
The Allison would be overkill for anything but a ridiculously bombed 4BT. The older 545's aren't electronic but would require an SAE adapter. The newer ones (1000/2000 series) are electronically controlled and can bolt to either an SAE adapter or a Chevy adapter with the right bellhousing.

Yes, it is heavier than a 47RH.

What is "special" about the Allison is that EVERYTHING inside is far larger and beefier than the 47RH or other light duty automatic trans. If you look at the internals between the two a LD trans like the 47RH looks like a toy. You don't need a bunch of high $$$ billet parts to hold up to large HP levels.

IMO, if a 47RH or 4L80E with stock planetaries, shafts, and drums holds up to your engine, then run it. If you need a bunch of high $$$ trick parts and fat stacks of thin clutches to make them live, then you are money ahead to go with the Allison. It can handle more power and live longer doing it.
 

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Maxpf the most I would need would be a transmission for a 300hp 4BT.

I dont think I will ever try and make more than that. I will try and use a single turbo for the 300hp and if I can get more thats fine but I only need the tranny to be strong enough for 1 turbo 4BT.

Not sure what type of HP I will gain when I use CNG with the diesel but I am guessing that if I build a 300hp engine adding the CNG will give me maybe 50-75hp maybe?.... SO I dont think I will ever see 400hp but I think the 47RH will still handle 400hp just fine.

COuld be wrong but that is just my understanding as far as the transmissions are concerned.

Allison sounds pretty sweet to say I have but I dont think I could afford one.

Plus like I was saying does anyone think a nube like myself could learn how to work on them?

I hope the only thing I would be doing is putting in parts that would clearly hold up to the abuse of the engine and my right foot. I am not saying I will understand everything about the transmission just enough to do what I stated above.

I remember replacing the seals on a transfer case and I thought I would have no clue. Then someone told me it is extremely easy and just take your time and you will be fine. Weekend later(I didn't have the right tools for the job) and I had replaced the seals and made my ford 205 transfer case a 4:1 also. Was pretty exited.

But trannys are a bit intimidating to me so thats why I am asking all the newbie questions.
 

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cheapest and,i think,best value with a 4bt is the 47rh.next up the expense ladder is a 4l80...you can easily have $3000 plus into a 4l80e with aftermarket controller.(personnal experience).

ultimate is an allison.requires a rather expensive aftermarket controller.very strong,very expensive.also pricy to rebuild.not for the budget minded.ali's are electronically controlled to such an extreme,that an electrical or electronic problem in he right spot,will not allow it to shift into ANY gear...effectively leaving you on the side of the road.iirc,they're shifted entirely clutch to clutch...no sprags.

at least with the older 4 speeds,you should get 1st and reverse at a minimum.
 

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Does the 47RH bolt to a plate then to the 4BT?

I am just wondering if I will have to buy the plate for the 47RH to bolt up to. And if I do need the plate is it expensive or no?

I was looking at buying someone's 4BT from the forum and they have an adapter already placed on the 4BT for the turbo 400. Wait ...come to think of it didn't all the Frito lay trucks have this adapter?

Anyways just wondering what I would need to bolt the 47RH to the 4BT?

And is the 47RH easy for a beginner to work on?
 

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>> Wait ...come to think of it didn't all the Frito lay trucks have this adapter?

Can't answer for Frito... My Wonder Bread truck has a Ford adapter. It is a 4 speed manual transmission.
 

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the chevy adapters are exspensive, I got a dodge adapter with all the bolts and a flexplate for $175 off of ebay, I looked into all the options and the 47rh was alot cheaper to buy/ and repair if need be/ compaired to the 4l80e, and I even have the 4l80e that needs repair, I was able to buy a 47rh and have it shipped cheaper than I could repair the chebby unit
 

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47rh it is then!!

oh what type of transfer case would work with the Dodge?

I prefer something very simple like the np205 or something like that.

Ok I am clueless about this but I need a passenger side drop for the front shaft so I dont know if that makes a difference for transfer cases or not. I know you could flip a transfer case over but not sure how that works or the levers. Sorry if this is a dumb question
 

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Dodge put a passenger drop 205 behind the A618/47RH, so finding one with the adapter shouldn't be too much of a hurdle.
 

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I'd get a Goerends torque converter while in the planning stage to save having to pull it out later. A Stock TC will never hold up to 300 hp.
 
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