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Discussion Starter #1
HI guys as i stated in my introduction post, i am planning on converting my 1972 winnebago 22ft brave with a dodge 413 in it now and a 3 speed auto(i imagine its just a tf727) I have a 1991 1ton dodge i got for free from my boss and the 12v cummins runs like a top as well as 1-3 of the tranny but since i dont have a working speedo i dont know yet if the o/d works plus its got 400k on the odo.

So my question is this, which tranny to use the stock o/d unit and have it rebuilt(trying to stay fairly cheap as i only payed 200 for the m/h and nothing for the dodge) or an allison or?

the weight of the m/h is roughly 10k and i am going to be pulling a 24ft trailer with a full size jeep and a smaller daihatsu rocky (all add up probably to 7-10k with the trailer weight as well)

I want the tranny to last and shift normally it doesnt have to be anything special just get decent gas mileage and be able to tow it without any problems.

I also have a diesel speced th400 out of a diesel motorhome but it needs rebuilt.

any thoughts?
 

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The old 727 is a fairly bulletproof tranny. There are all sorts of upgrades and kits for them and not too pricy either. I just never heard of hookn one to a cummins, would be cool to see though:thumbsup
 

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Go with the 518. I makes a good package. I have a friend that converted a 72 Travico. He used the 518. He pulls around 14 MPG with it loaded for camping.

With 1st gen mounts on the engine it sets right on the 413 mounting position. Yours has room for an intercooler in front of the raditor. I have a brother in law that has a 74 Winnebago. I have looked it over for a swap. You will need a forward faceing air horn. The side faceing air horn off an IC truck will most likely hit the engine cover. Plus you won't have room to get a IC tube to it. A non IC intake is to tall for the engine cover.

Here is a pic of his travico.




The part of a 1st gen in the back ground is Greenleafs. :D
 

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Dodge did put the 727 behind the CTD in some of the 1st gens. My buddy's got a '91 with 350,000 or so on it and the stock 727 and it's still running fine.
 

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Discussion Starter #5
guys thanks for the input, I have been thinking all along for sure that it should essentially drop right between the frame rails of the winnie as phillip said.

Do you think the 518 that is in it with a decent freshning up can handle towing as well as the weight of the winnie?
 

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Discussion Starter #6
So what all do you recomend for this swap after it is all said and done.

it has a dana(70 or 80) i have not gotten the gear ratio off of it but i assume it to be 3.54 to 4.10's i will verify

on my list i have a pyro guage, smaller exhaust housing to get the speed up quicker, since i will be flying a brick into the wind there is no point in trying to get much above 70mph

what else im gonna round this stuff up while it is in the dodge now so that i can drive and test everything.
 

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You should just make the m/h a trailer and pull it with the truck. Then you could still use the truck when you weren't camping ;)
DS79
 

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Don't be surprised if you don't find 4:30 or 4:56 gears in it. The gasser had more RPM to play with compared to a CTD.

With all the extra weight your going to be pulling I would look for a 47RH. It would give you a lockup converter. Being its 2Wd they are easyer to find than a $X$ model. If you use the Dodge PCM for trans controll all you would need to address is the lockup function. There are a couple of ways of doing that. You can go manual control or set up a pressure controll system.
 

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speaking as a guy with a stock 727 behind the cummins, i would recommend updating the converter. it is pretty loose, and has too high stall speed.
 

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My stock converter in my 727 reminds me of driving a front end loader. I can power right thru the converter. Also a 3 speed with low gasser gears. Rev city at 50 mph.
 

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Discussion Starter #12
what rigs would i find the 47rh in? and according to the strength thing it isnt to much more than a 46rh(518) which i have....perhaps i will just swap in the 518 and then if it goes south find a 47rh and swap it in
 

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The 47RH's were used in 94/95 CTD truck. If your going to use the 518 replace the converter before you install it. They were a very loose converter from the factory. Towing heavy made it worse on slippage.
 

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I see, I was just messin' with you anyways, those are some sweet rigs BTW.
DS79
 

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Discussion Starter #15
deerslayer, i knew you were:) the FSJ i am building for my wifes trail rig and a recovery vehicle and the tracker is my little $300 beater that i can do whatever i want to.

phillip, by loose you mean higher stall? i.e. 2000 instead of low down 700-1200? i will definately get a lower stall ratio if thats what you are refering to.

As for the m/h gear ratio's i am not opposed of swapping gears, the axle itself looks alot like the axle in my dodge just 5 lug instead of 8 lug(i will have to pull casting numbers to find out)
 

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Don't be surprised if you don't find 4:30 or 4:56 gears in it. The gasser had more RPM to play with compared to a CTD.

With all the extra weight your going to be pulling I would look for a 47RH. It would give you a lockup converter. Being its 2Wd they are easyer to find than a $X$ model. If you use the Dodge PCM for trans controll all you would need to address is the lockup function. There are a couple of ways of doing that. You can go manual control or set up a pressure controll system.
I'd agree wholeheartedly. You'll likely find that the mh is geared too low for the CTD to run at an appropriate highway speed and to get decent fuel economy. You really need the OD. The lock-up convertor also gives you a 10% engine speed reduction for a given road speed. You need a beefy lock-up converter, but that will also reduce your transmission temps hugely. I don't know how Dodge ran theirs, but a lot of the Allison's lock up in second gear. Most gassers don't lock up until high gear over 60 KPH (36 MPH) and it's the first thing to go under even moderate load, well before it shifts out of high or od. What you'd like it to do on the diesel is to stay locked up and let the trans do it's job when pulling up those steep hills. If the convertor didn't unlock and the trans just downshifted you wouldn't see your trans temp budge a degree.

I'd be reluctant to do a manual hook-up for the lock-up. Too much risk of forgetting to unlock when you want to stop or in a panic stop. Even if you wired it through the brake switch, as soon as you let your foot off the brake it would lock and away you'd go. If that 47RH is not a totally electronically shifted trans you could fool around with pressure switches off a (trans) governor pressure tap. If it is electronic, you'd have to live without the configuration it's programmed with.
Be a fun project though.
Steve g
 

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Discussion Starter #17
ok so here is what i have

winnie with a hd70 and 4.56 gears(verified just now) big 5 lug

dodge with a ?(i imagine its a 70, possilby a hd but cannot find the bom) and 3.54 gears. 8 lug

i wonder if the front setup is interchange able, maybe i will just swap axle for axle and swap the front dodge disks on the mh
 

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Aloha Malodin,

Here is my take on your project. First of all it sounds great.

As you've gathered, the 727 is a bullet proof transmission but the non-lockup torque converter (TC) is a waste of time. I had a '90 CTD / 727 auto and the stall speed was 2000 and higher -- sometimes 2200 going up steep hills.

I had a yr 2000 Dodge CTD w/auto and it was also miserable in non-lockup mode. Once locked it would pull like gangbusters. Unfortunately, the clutch is supposedly rather small and not intended for heavy torque on a continuous basis.

While going through my TC woes, I learned about the later Ford automatic transmissions w/lockup TCs. If my source was right, the Ford is capable of manual lockup in any gear -- different than the Dodge lockup TC only in the 2 highest gears manually.

There are some excellent aftermarket torque converters out there that can provide a beafy lockup clutch in the TC that can withstand a long life of real towing torque. Apparently the later Dodge (stock) lockup TCs have clutches in them that are only intended for cruising, not heavy torque.

Do some shopping around -- some aftermarket TC manufacturers claim 92% torque transfer in non-lockup mode. That is pretty impressive if its true. The stock Dodge TCs max out at around 70% torque transfer in non-lockup mode. The Cummins can spin itself right through the stock older TCs.

I'm not a pro like many of the members here but this is what I learned during my diesel upbringing. I hope you can use some of it.

Aloha, Dean.
 

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With the loads your going to be towing I would still look for a lockup converter trans. Even the best remaned converter will still leave you with a fluid coupling. You don't say what state your from. If you have any hills to go over. A fluid coupleing converter is going to slip. A lockup is going to put everything to the ground.

If that winnie has the same rear axle as the travico my friend did it is a 70HD. 4:56's are to deep for a CTD. You would need a trans with a double OD like a allison 1000 6 spd. The gear spread on a 1000 6 spd would work well towing with it.
 

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Discussion Starter #20
captain, thanks for the info i will do alot of research before i figure out exactly what tranny to use.

philip, i live in washington state and hills are abundant here.

it does have the 70hd with 4.56's so i new it would be to deep for the CTD is the allison 1000 automatic if so i might have to find one of those, i like the idea of having the extreme takeoff power from the 4.56's

my only concern is cost as well, i am keeping it on the cheap.

currently i do have the 518 tranny(o/d) behind the diesel as is, so my thought was to get that in and up and moving then find a good tranny to replace it when i do finally burn up the tranny
 
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