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I would like to run an automatic transmission that I can shift from the floor with that would make a 4bt the most fuel efficient. Maybe something with an overdrive? It doesnt need to be bomb proof as I will be running the engine stock and in a croozing hot rod.
 

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Great question, I will need to research this too for my next 4BT swap into a Grand Waggy.

The 4L80E is from what I read one of the strongest OD transmissions, it is electronically controlled, which was a bottle neck, but there is some sort of unit available to make this not a problem anymore. What does this unit come stock in?

Please correct me/elaborate on this everyone. :)
 

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4l80e trannies came stock in 3/4 and 1 ton Chevy and GMC Trucks, 3/4 Suburbans and I believe vans. They began with the introduction of the throttle body injected motors in 93? and continued up until 2001 when the one switched body styles. They were also installed behind diesels and you can get some tough trannies from the diesel performance guys. There are a couple companies out there that make shift controler computers for them. I believe you can also buy a shift kit from B&M to de-electrify them. It is a very tough tranny in stock form, they use all the same internals as a TH400 (clutch packs and what not), and have the addition of an OD gear. My 93 chevy has a 4L80E and I had it rebuilt not to long ago, that's how I found all this out.
 

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My personal thoughts & preferences on this are:

I want an engine that is NOT computer controlled.

I want a transmission that is NOT computer controlled.

I want reliability and serviceability using available off the shelf parts should I require it.

I want a long time proven and tested system verses something expensive and still somewhat experimental.

My reasoning - You have an engine or transmission failure. What happens if you are out on the road beyond reasonable economic towing distance to home. This is your Frankenstein conversion vehicle. How many shops would be willing to tackle the reverse engineering involved to test or repair an aftermarket computer control system?

For the above reasons I would not hesitate to put a Dodge Cummins version 47RH behind a 4BT engine.
 

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Discussion Starter #7
thanks

Thanks guys for all of the input. As BobS suggested, I am definitely partial to a completely non electronic setup. I am more of a mechanical guy and it would seem to be much less expensive and easier to install and maintain anyways. With that being said....what other comparable transmissions would any of you suggest I take a look at and compare?
 

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My personal thoughts & preferences on this are:

I want an engine that is NOT computer controlled.

I want a transmission that is NOT computer controlled.

I want reliability and serviceability using available off the shelf parts should I require it.

I want a long time proven and tested system verses something expensive and still somewhat experimental.

My reasoning - You have an engine or transmission failure. What happens if you are out on the road beyond reasonable economic towing distance to home. This is your Frankenstein conversion vehicle. How many shops would be willing to tackle the reverse engineering involved to test or repair an aftermarket computer control system?

For the above reasons I would not hesitate to put a Dodge Cummins version 47RH behind a 4BT engine.

HERE, HERE, BRAVO!!

Couldn't agree more! Under normal useage the 47RH was/is fine behind a 6BT. Problems come up with heavily modded 6BT's or HEAVY TOWING, not from normal use. Translation: stupid people don't know how to take care of an automatic transimission, like adding a tranny cooler, changing fluid and filter, adding a trans temp gauge to see when they are cooking it!

Behind a 4BT, a 47RH [A-618] would live for years, if properly cared for, like changing fluid/filter and using a tranny cooler. They're a topnotch stout tranny!

They were used behind every year Dodge Cummins Turbo Diesel, but some '89's aren't quite as strong as all the later years.

Gotta add: a large majority of the 4BT stepvans, and that's not 6BT but 4BT, had continuous failures using the GM TH465/475, the beefiest available then. My stepvan had gone through at least three, and this is one of the major reasons that Frito Lay decided to get rid of 4BT trucks, because of costly GM trans failures. Folks can say all they want about how wonderful they are, but talk to Frito Lay....
 

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It comes down to what I have always believed:
Diesel Engine + Auto Tranny = :( no matter what brand (besides allison $$)
Stick to...well...a stick

Also, I've known of 4l80e's lasting 220k behind a diesel without constant heavy use (towing , high hp)
 

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The last DoveBid auction listed a 4BT stepvan with an Allison. Defects listed in that auction included the transmission being listed as bad.

The 4L80E's have a good reputation when installed behind a factory engineered engine option. The problem is there is no known factory 4BT engine option for it. You can not expect the same manufactured life expectancy and durability anytime you operate it outside of the factory engineered parameters. I personally consider this as an experimental area pending results at 100K miles of service behind a Cummins B series engine.
 

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Another thing to consider about the trans failures in the step vans. These are heavy 1 ton trucks, driven mostly driven by guys who DON'T care at all about the motor or truck. They were abused terribly.
Also, the SAE housing that you get with the motor might help determine which trans you get. Certain motors came with GM housings, etc., unless you want to try to sell or swap your housing.
I have the GM housing. I'm putting a 700R4 in my Dodge 1/2 ton, 2wd. Non-computer controlled, with O/D. I know some don't like them, but they were in many GM 1 ton trucks and lived fine there. Plus, my trans guy says it'll hold 400+ hp, and he builds them for street/strip cars.
 

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I have the GM housing. I'm putting a 700R4 in my Dodge 1/2 ton, 2wd. Non-computer controlled, with O/D. I know some don't like them, but they were in many GM 1 ton trucks and lived fine there. Plus, my trans guy says it'll hold 400+ hp, and he builds them for street/strip cars.
The questions here are 400+ HP at what RPM and how much torque at what RPM? The problem here is those street/strip cars are generally lighter in overall weight and produce their peak torque at two to three times the 1800 RPM where the Cummins torque peaks. As an example lets build a big block Chevy engine that has 400 HP & 400 FT/LB torque at 5252 RPM. Lets also factor in a stock Cummins 4BTA that is producing 120 HP & 300 FT/LB of torque at 1800 RPM's. At 5252 RPM the 700R4 is operating within its engineered parameters. It has all the torque holding power from idle through the 5000 RPM range. The problem comes in when you hit the transmission with 75% of that torque while it is turning less than 33% of the 5000 RPM range where it achieves it higher clamping power. In other words you are operating outside of the engineering designs in an unproven area. Sort of like driving tacks in a board with a sledge hammer. I am not saying it can't be done. I have nothing against experimenting except it is generally expensive. ;)
 

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I'm keeping my 4BT stock for the most part, only adding a gov spring so far and the ZFS5-42 tranny I have will work with it, plus a few upgrades and still give me what I consider a nice "buffer" before it's ft-lbs/torque rating will be surpassed. It's a 5 speed stick that was in the older Ford trucks, it is mechanical with a speedo sensor on it (though I don't know that the speedo sensor was on all the years of this tranny). It comes in a 2WD and 4WD model as well. There's a post on it somewhere on here. :tongue:


Pantherman
 

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The questions here are 400+ HP at what RPM and how much torque at what RPM? The problem here is those street/strip cars are generally lighter in overall weight and produce their peak torque at two to three times the 1800 RPM where the Cummins torque peaks. As an example lets build a big block Chevy engine that has 400 HP & 400 FT/LB torque at 5252 RPM. Lets also factor in a stock Cummins 4BTA that is producing 120 HP & 300 FT/LB of torque at 1800 RPM's. At 5252 RPM the 700R4 is operating within its engineered parameters. It has all the torque holding power from idle through the 5000 RPM range. The problem comes in when you hit the transmission with 75% of that torque while it is turning less than 33% of the 5000 RPM range where it achieves it higher clamping power. In other words you are operating outside of the engineering designs in an unproven area. Sort of like driving tacks in a board with a sledge hammer. I am not saying it can't be done. I have nothing against experimenting except it is generally expensive. ;)
As I said, some don't like them!
I don't intend to get into an argument about which is the best trans. The upgrades will handle the low rpm issue's.
If you have a suggestion on a better trans to use, I'll consider it.
 

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As I said, some don't like them!
I don't intend to get into an argument about which is the best trans. The upgrades will handle the low rpm issue's.
If you have a suggestion on a better trans to use, I'll consider it.
Incorrect assumption. I have been a GM biased person since 1965. I really do like them where they were engineered and designed to be used. My point is that they have not yet been proven through third party re-engineering which generally does not provide the best bang for the buck. In other words when I start reading about it being proven, reliable, more economical to purchase, going over 100K miles behind a Cummins B series engine with nothing more than normal interval fluid and filter changes, then I will call them the best thing since peanut butter was invented. BTW, no intent of argument here. I'm actually looking forward to reading your buildup thread and hopefully your test results over time if you go this route.
 

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My suggstion would be for the Dodge 47Rh be sure it is a 47RH with lockup & overdrive which was used in 1994 & 1995 not an older 46 Rh used in the 1st gen body style. 1996 you may find 47Rh still but this was the begining of the 47 RE (electronic). If not this then a Ford 4R100 built by BTS (brians truck shop lead hill arkansas) with a standalone controller.
 

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Incorrect assumption. I have been a GM biased person since 1965. I really do like them where they were engineered and designed to be used. My point is that they have not yet been proven through third party re-engineering which generally does not provide the best bang for the buck. In other words when I start reading about it being proven, reliable, more economical to purchase, going over 100K miles behind a Cummins B series engine with nothing more than normal interval fluid and filter changes, then I will call them the best thing since peanut butter was invented. BTW, no intent of argument here. I'm actually looking forward to reading your buildup thread and hopefully your test results over time if you go this route.
I do have to admit second guessing the decision, based on the posts here. I'm not electronic savvy enough to mess with a 4L80E /computer trans, although the info available here is great.
I doubt I'll put 100,000 miles on it, as I expect only about 6000 a year. It will be my summer daily driver/cruiser/occasional dragster.
 

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i dont know if you have an adapter for chevy , but dodge 6bt adapters are dirt cheap and will bolt directly to a 47rh from a 94-95 dodge diesel truck and just need a switch for the overdrive. plus are proven trannys.

on the other hand you can go chevy , buy adapter $$ , buy a pcs tci,compushift,or craft a oem tcm $$$, seems like a $$drawback$$ to me.

the nice thing about having a electronic tranny with a standalone controller
its that most units are programmable which give you total control of the shifts plus they have 2 programming modes , like normal (nice softs shifts) & tow mode (hard more clamping power). my 02
 

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i dont know if you have an adapter for chevy , but dodge 6bt adapters are dirt cheap and will bolt directly to a 47rh from a 94-95 dodge diesel truck and just need a switch for the overdrive. plus are proven trannys.

on the other hand you can go chevy , buy adapter $$ , buy a pcs tci,compushift,or craft a oem tcm $$$, seems like a $$drawback$$ to me.

the nice thing about having a electronic tranny with a standalone controller
its that most units are programmable which give you total control of the shifts plus they have 2 programming modes , like normal (nice softs shifts) & tow mode (hard more clamping power). my 02
My motor came with a GM trans and adapter. I'm re-thinking the 700R4 idea, and researching the 4L80E idea. I really like the programmable idea.
 

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through my research, 47rh is the best way for me and i am putting it in a gm truck. no where near as much money, grab a hobbs switch and roll. Got it on a pilot now and hope to have mine rolling by fall. the only bad thing i have heard about it is the stock TC.
 
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