i want to build my own 47RH ???

[1970 300 SEL]

greeting all.

i ve done searches here, ramchargercentral, TDR, and yahoo.

im not finding the answer im looking for. i am interested in building the 47RH myself. im attending college and have a automatic transmission course coming up.

so i thought it would be a good idea to build my own for "educational" purposes.

im thinking, find a 2wd core and build it my self (minus tc) and convert to my 4x4 2500.

first off i cant find out if the trannies will intercahnge with something simple like extension housing swap and output shaft

more importantly i cannot find detailed information on build information.

i know that many builders use oem clutch plates but reds or raybestos arent much more. im curious to more detailed mods like servo/valve body, gear train ect ect.

my problem stems from the fact that a lot of cummins operators are affraid to perform maintenance on their trucks. the previous owner was the same way. he had to pay some one to slide the plate forward and a few other things. a lot of guys keep saying "just buy one". thats fine and dandy. i have the money, but i want to tackle this for experience purposes.

i ve allready looked at PATC and i know they have quite a selection.

i also have a FSM and the ATSG 618 book.

im not really sure what i will need for 350hp with room to grow as far as transmission mods.

any builders out there willing to help a guy out?

[mondtster]

Get a 4x4 transmission core. You could technically do it starting with a 2x4 core, but you would need an OD/t-case adapter and output shaft, and at least around here it is hard enough finding a core tranny much less finding a few parts.

Building these trannys is easy. They operate just the same as the older torqueflites and the ford c4. They will respond to the same types of mods that you would do on one of them too.

It sounds like you're just looking for a mild build. I'd just go for a relatively stock rebuild using a transgo valve body kit and a good torque converter. Stock clutches and clutch count will work fine for your requirements.

EDIT: BTW, don't listen to anyone saying that you can't build a decent tranny in your garage. I don't believe that there is anything that the big guys do that can't be replicated at home. The exception to that rule however would be torque converters.

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Last edited by mondtster : 06-24-2008 at 12:06 AM.

[1970 300 SEL]

thank you for the reply.

so, i can use my choice of converters (i guess they re all about $1000 give or take)

and trans-go's TFOD-Diesel

and be set? does this allow manual shifts?

will a simple shift kit give me enough pressure to keep me locked tight?

what about all of these other little valve body tweaks i see mentioned in PATC? necessary or a profit scheme for them?

how much room does this leave for growth? of course im looking at 350hp. ill occasionally tow a car trailer and my mustang (5000lb total). im not sure what i currently weigh in long bed standard cab form, so i cant quote total weight. this is also flat land so im not concerned about engine braking power, i just keep my distance.

my current tranny isnt blown and i dont really notice any slip, but i figure i could take a core and tear down inspect in class, drop my 4x4 tranny down in the weekend and swap my 4x4 parts to it?

my goals seem small, but i know its too easy to get more power so i need a little cushion.

[mondtster]

IMHO, a converter and the valve body kit are all that is really needed. I forgot to mention it before (I was really tired last night), but I'd also add a 4.2:1 intermediate band apply lever, a reinforced band strut, and a 5 or 6 pinion OD planet (stock is 4) as well.

The transgo valve body kit you linked is the exact one that I have in my truck. I have the line pressure turned up quite a bit and it shifts nice and clean and firm (not harsh). The kit is a complete kit and contains most of the other parts that PATC lists individually. It will allow manual shifts just like the stock one does, but it is still an automatic if you leave it in "D". If you want a 100% manual valve body transgo does make a "Stick Shift" kit that you could use as well.

If you're planning on upping the power output of the motor considerably and don't want to go through the tranny again then you may want to look at increasing clutch count and adding a billet input shaft. If you're planning on staying close to where you are currently at however, you should be fine. I have pretty close to the same power output and the same tranny that I have been beating on for a while now with no issues. Since I built it I am planning on building a compound turbo setup however, so we will have to see how well this basic tranny likes the extra torque.

I honestly think that people would be shocked at how close to stock most of these high test "racing" transmissions are. Tranny shops have always done a pretty good job convincing people that they are voodoo and that an average person couldn't touch one. 100% NOT TRUE!!!

[1970 300 SEL]

what is the comparison between the 4.2 and the 5:1 levers? stock is 3.8 or something? i understand they ll clamp tighter, but is there a draw back to the 5:1?

whats the consensus on billet? all the mall crawlers "need" it because the drag racers and pullers use it. i had one of the big name shops (*think* it might have been suncoast) state they have never seen a shaft failure on the street regardless of towing load. claim the only failures they ve seen were from shock loads like wheel hop on the strip or at the pulls.

any one care to disagree?

are there any actual figures to the point internal friction failures occur? something like a hp number?

Bands?:
i see all kinds of magic composites like kevlar or carbon fiber.

valve body pressure?
i believe the previous owner turned it up a little, i havent checked the oil ports yet. i have a code #37, will increased pressures trigger this? will a trans-go trigger this?

what about tc controllers and lock up line pressure increasers? necessary or waste of money?


sorry for so many questions. im 'bout to leave for UTI and want to make sure i have a bit of knowledge before i go in there just incase the class isnt very thorough.

[mondtster]

I've never tried a 5:1 lever yet, mainly because the general consensus on it is that it will cause 2-3 shift issues. You have to pull the tranny to replace the apply lever and I'm lazy, so I've avoided them. The stock apply lever should be a 3.8:1 in the diesels.

As far as billet shafts go, it really depends on what you're going to do with it. If you don't increase your power too much more and drive normal, then you probably don't need new shafts, but if you start getting greedy with the power and/or start to drive aggressively, race, or truck pull then I would consider it. I've seen some pictures of input shafts that have shattered inside the stator support and it took out the shaft, the pump, and the converter.

As far as friction and band materials go, there are way too many variables involved with that to have a clear cut torque limit on that sort of thing. I would either use stock or alto reds on both the clutches and bands. If you search around, there is some info indicating that the kevlar bands will actually slip a little so they generally aren't recommended except in full race applications. The guy who first taught me how to rebuild trannys is a well known Ford c4 tranny builder and pretty much all his builds use stock clutch and band material. There hasn't been any issues there, even when putting a c4 behind a big block.

As far as line pressure goes, you have a 47rh. They aren't electronic. There is nothing inside it that will cause a code 37 to show up, nor do you have to worry about it. If I remember correctly, the code 37 is for a trans temp sensor so I'd be checking/replacing the sensor to get rid of that.

I personally think that the tc lockup controllers and line pressure raisers are a waste of money. I had the line pressure raiser kit installed on my truck when I bought it and all it did was bind up the tv cable arm. I ripped it off there and threw it away. There is plenty of line pressure generated from the valve body if you set it up right.

Just keep in mind that there are a lot of aftermarket parts out there for torqueflites, but like I said before, I think most people would be amazed at how close to stock their $5000 "racing transmissions" actually are. My buddy has been racing for over 9 years on a stock rebuild a727 with only a turbo action valve body in it and it has never even been opened up in those 9 years for service or inspection. That just goes to show you what a good valve body can do for you.

[Diesel Nut]

All sound advice.

Yes, you can convert the 2wd to 4wd, but like posted, just find a 4wd if you can.

I would make sure you get the rigid band. You don't want the flimsy stock style. Red frictions are going to have more bite and more durability than stock fritctions. As for steels, there are arguments for and against stock steels vs Koleen steels. For you I think stock steels would be fine.

Now, since you mentioned towing. Yes I have seen a few shaft break towing, but remember that a CR motor can easily reach 500hp with little mods, and this does not take into account that the shaft may have been injured when the trailer was not attached. Fine stress cracks can grow to breakage. If you plan to be rough with it upgrade it while you have it apart.

The 5:1 has more clamp, but is also slower to react. 4.2 seems to be a nice complement of the 2.

AS posted, the TFOD-Diesel is all your VB will need. Just keep your ASTM manual with you so you remember where all the check balls go!

Soak your frictions in ATF prior to stacking them. Best bet is get an old 1 gallon ice cream bucket (with lid, so you can reuse it) and dump a quart or 2 in there. You can soak the whole clutch pack, take it out, and soak the next pack while you build the previously soaked pack.

Take your time, keep everything clean, and you should do just fine!

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[dezl]

good question man, I have been doing reseach as well and I cant find anything. I cant justify paying that much cash for a tranny. I would much rather do it myself any how

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94 f350 w/ 95 6bt, Nv4500, Valair clutch, 370 Hp Marine Injectors, #4 fuel plate, dodgezilla hybrid turbo, 18* of timing, lazer cuts, 4k GSK, 60lbs springs and a lot more!

[1970 300 SEL]

im still getting used to my ctd.

is there a way of preventing OD under a certain speed w/o manually pushing the dash button?

when i coast it remains in OD down to atleast 25mph and just barely over idle.

how does this OD engage? with the switch off does it always remain in OD and shift through the other 3 gears?

[Joe G.]

The OD button locks out OD when the indicator light is on. I made the button more convenient by installing a shift lever from a '99 that has the button on it.

OD happens when a ground is applied to the wire to the OD solenoid. The PCM controls that, but you can change it. The same thing is true for TC lockup. You can set the shift points for these functions by adjusting the TPS or modifying the TPS circuitry including completely replacing the TPS.

You may be confusing OD with TC lockup in some cases.

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KDP tab fix info and fuel system article jgeorge1@suddenlink.net '95 2500 CC auto 4X4,3.54,Combo EGT/boost guage,PacBrake,TST #5,370 injectors,DTT TC/VB, Cummins chrome kit.

[luckyhat12]

I just wanna subscribe. I am gonna try to build my dad's 700R4 when we build the motor and this is good info to know.

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--Chris-- 07 Silver QC LB 3500 5.9 4X4 G56 w/ SBC DD, BD Ex. Brake -Full Time RV'er-

[1970 300 SEL]

700r4s operate slightly different.

JoeG, i understand ground interuption and the 2 switched grounds from the PCM

i also understand when i press the OD off button that OD is locked out.

im trying to understand what happens when i dont push the button.

lets say i just jump in and drive. does the OD gear set remain engaged or does it still have minimum parameters in order to engage? (like tps vss rpm ect ect)

i am trying to understand what will dictate a closed throttle down shift.

when im heading into a town from 55mph, i simply release the throttle and coast down to city speed limits. it remains in over drive until i blip the throttle hard enough to force a down shift or when i press the lock out button.

curious if there is a way to automatically force a closed throttle down shift under a certain speed.

if im reading my ATSG manual correctly, the governor port is a representative of vehicle speed

if thats the case it seems to me a pressure switch that opened under a set pressure and wired inline with the OD wire would open the ground path, preventing OD under that speed?