1800joedaddy
Registered User
So the speedo will still work. Thanks
1994 Ford Cummins conversion
- Thread starter ncovey
- Start date
So the speedo will still work. Thanks
That may be true for a stock vs. stock engine comparison, but for a Cummins making 1000+ ft/lbs of torque, there is no way I would expect the ZF to live for very long. The only thing that I have seen for a big problem on the NV4500 is the 5th gear nut, which can be fixed with new mainshaft. I have personally replaced more ZF transmissions behind stock IDI's and powerstrokes than I have seen problems with the NV4500. As far as ratios go, I don't think either one are too whoopy. If you could pick and choose ratios from both transmissions to put into one, you would have a great transmission. It makes you wonder if they ever drove a diesel truck before, for either company. This isn't meant to be a flame, just my opinion and experience.
Just a little trivia I found about the speed sensors, Ford and Dodge used the same speed sensor in the 90"s. The Ford harness will plug into and read from the Dodge dana 80.
averagef250
Full Access Member
Well, I have a ZF 7.3 diesel S5-47 running around behind a worked 913 P7100 24 valve with lots of additional goodies in a customers 86 F350 crewcab dually 4x4 60 front 80 rear, 205 case, yada yada. The truck weighs 10K empty and the crazy guy has towed nearly double the legal limit with it doing hotshot work. No idea how many miles are on it, but it's been driven daily for the past 5-6 years, cross country over heavy grades with big weight.
The truck can light the duals in any gear. Seat of pants dyno says it's in excess of 1000 lb/ft, but I could care less.
Point being I'm very familiar with both NV4500's and ZF 5's and 6's and 4500's do not impress me. I could ramble on about the 5th gear issues and how much you actually have to sink into an NV4500 if you want it to hold up working it, but I won't. My advice is buy an S6-650, 5600 or G56 when your NV4500 gets sloppy or spits 5th.
All the ****** ZF's I've seen have been repaired by people that had no idea how to work on them. I pulled an Alltrans "rebuilt" ZF5 from a customers truck with 20 miles on it that had .010" main thrust clearance. Nothing was bad inside, just a moron assembled it and had no idea how ZF's work.
The ZF diesel transmissions do have very nice diesel ratios. To say otherwise is interesting to me. Maybe you've driven some messed up trucks, but plot the RPM drops out. I don't see how you could improve it for a close ratio truck 5 speed.
The truck can light the duals in any gear. Seat of pants dyno says it's in excess of 1000 lb/ft, but I could care less.
Point being I'm very familiar with both NV4500's and ZF 5's and 6's and 4500's do not impress me. I could ramble on about the 5th gear issues and how much you actually have to sink into an NV4500 if you want it to hold up working it, but I won't. My advice is buy an S6-650, 5600 or G56 when your NV4500 gets sloppy or spits 5th.
All the ****** ZF's I've seen have been repaired by people that had no idea how to work on them. I pulled an Alltrans "rebuilt" ZF5 from a customers truck with 20 miles on it that had .010" main thrust clearance. Nothing was bad inside, just a moron assembled it and had no idea how ZF's work.
The ZF diesel transmissions do have very nice diesel ratios. To say otherwise is interesting to me. Maybe you've driven some messed up trucks, but plot the RPM drops out. I don't see how you could improve it for a close ratio truck 5 speed.
Like I said before, it wasn't a flame, and I wasn't trying to start a ******* match. I simply was stating my thoughts, and experience. You like the ZF, I like the NV4500, it is a free country. If everybody liked or had the same thing, it would be a very boring world.
Mudbillyrednec
Full Access Member
Any updates on how the motormounts have held up or worked out for ya....I ask becouse I'm getting ready to do my 94 F350 CC 12V swap sometime nextweek....
May I ask what or where you got your exhaust manifold from ?? Fordcummmins want $300 for theres ....seams pricy for this countryboy ? ( mine is out of the 1990 and dumps in the center cyl out at a 45 deg angle ) I'd like to someday hook up my A/C !
I am on the fence if I should buy new stock mounts, and ask you for dimensions on what you built ?...or buy the fordcummins ones for $260 ???
It's a 6" lifted 4x4 and I wasnt sure...but i'd like a small body lift to help with washing .....being hear in the salt belt of MI
So...what size bodylift would you recomend ? and did it make an aftermarket steering rod absolutely Neccesarry ?
I ask these ?'s becouse I'll be using my friends shop, and dont want to jam him up while I trial and error
May I ask what or where you got your exhaust manifold from ?? Fordcummmins want $300 for theres ....seams pricy for this countryboy ? ( mine is out of the 1990 and dumps in the center cyl out at a 45 deg angle ) I'd like to someday hook up my A/C !
I am on the fence if I should buy new stock mounts, and ask you for dimensions on what you built ?...or buy the fordcummins ones for $260 ???
It's a 6" lifted 4x4 and I wasnt sure...but i'd like a small body lift to help with washing .....being hear in the salt belt of MI
So...what size bodylift would you recomend ? and did it make an aftermarket steering rod absolutely Neccesarry ?
I ask these ?'s becouse I'll be using my friends shop, and dont want to jam him up while I trial and error
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jimraelee
Full Access Member
very nice project... as mention, Im jelious of your conversion... I added a turbo to my stock idi 7.3 and thats all I will spend on it... I too am looking to make a cumins swap with the hopes of getting it to the 500hp mark without killing anything... Im kind of torn though... you all talk about the manuals... I want an auto... I dont like haveing to shift anymore... anyone have ideas on good auto conversion without going to an allison???
Any updates on how the motormounts have held up or worked out for ya....I ask becouse I'm getting ready to do my 94 F350 CC 12V swap sometime nextweek....
They seem to be doing great, but I have only put about 1500 miles on them, no towing. I had problems with my clutch, but I have a new one, so hopefully she'll be towing this weekend.
May I ask what or where you got your exhaust manifold from ?? Fordcummmins want $300 for theres ....seams pricy for this countryboy ? ( mine is out of the 1990 and dumps in the center cyl out at a 45 deg angle ) I'd like to someday hook up my A/C !
I had a core motor, that had it on it, so I couldn't tell you on the cost. The core came from a F700.
I am on the fence if I should buy new stock mounts, and ask you for dimensions on what you built ?...or buy the fordcummins ones for $260 ???
Don't buy a thing from Ford Cummins, they are over priced have horrible customer service. The easiest thing to do is set your motor where you want it, and build your mounts to fit. You will be much happier with it when you are done. Using the stock style mounts, I don't have any weird vibrations, and I am not too worried about breaking them. The left side is stock 12V, and the right is stock 24V. As for the dimensions, I would give them too you, but I didn't right them down, smart, huh?
It's a 6" lifted 4x4 and I wasnt sure...but i'd like a small body lift to help with washing .....being hear in the salt belt of MI
I wouldn't worry about the body lift, there is plenty of room in there for the Cummins. If you can wash your 6.9L you will have plenty of room.
So...what size bodylift would you recomend ? and did it make an aftermarket steering rod absolutely Neccesarry ?
I didn't use a body lift, so I couldn't tell you.
I ask these ?'s becouse I'll be using my friends shop, and dont want to jam him up while I trial and error
.....
ameristar1
The One Blue Thing
Put in a beefed Mopar auto that came with the Dodge Cummins or possibly a fully worked 4R100. Lentech builds killer spec Ford automatics to survive behind 1200hp drag motors. Look them up at lentechautomatics.com
Mudbillyrednec
Full Access Member
Thank you for answering my ?'s
I have herd several bad things from others about Fordcummins.....They seam nice on the phone.......But I dont like there price for what you get
maybe someone will pm me dimensions on proven mount set up's ????
I have herd several bad things from others about Fordcummins.....They seam nice on the phone.......But I dont like there price for what you get
maybe someone will pm me dimensions on proven mount set up's ????
averagef250
Full Access Member
The only two autos I will use behind a Cummins in a conversion are the 47RH or a SAE pattern Allison 2000/3000. The GM Allison requires an additional rediculously expensive adapter.
I prefer the 47RH. The 47RH has some quirks like all autos, but it's actually a very well built transmission and can be upgraded to handle almost anything. In addition there is no computer and I could build 5 bulletproof 47RH's for the cost of one beefed Allison and custom controller. The 47RH with a 48RE overdrive drum, transgo kit and aftermarket planets is very hard to break and will last a while subject to an abusive right foot.
For 90's ford mounts I prefer to use the 460 isolators flipped upside down and build my own engine side stands.
Every conversion is a little different and everyone has thier own idea of "the right way".
I prefer the 47RH. The 47RH has some quirks like all autos, but it's actually a very well built transmission and can be upgraded to handle almost anything. In addition there is no computer and I could build 5 bulletproof 47RH's for the cost of one beefed Allison and custom controller. The 47RH with a 48RE overdrive drum, transgo kit and aftermarket planets is very hard to break and will last a while subject to an abusive right foot.
For 90's ford mounts I prefer to use the 460 isolators flipped upside down and build my own engine side stands.
Every conversion is a little different and everyone has thier own idea of "the right way".
jimraelee
Full Access Member
thanks for the input... Id really rather mate up a dodge tranny to the cummins, heck its a bolt up right?? Adding the dodge controller for the trans is not a huge issue, but buying an aftermarket controller for the Allison is not my idea of money well spent. Heck I'm only looking to get 500hp out of the cummins. But I don't want trans problems either. Yes the new Allison may well be the Hercules of diesel trannys, but I don't need to spend that new model price on a unit. Oh yes add that trans adapter price... $800 for the adapter, come on.... I'm not made of money.
averagef250
Full Access Member
$800 is just the GM plate. You still need a flexplate and starter. $1400 is the average GM-Cummins adapter price said and done. Add $1000 for the Allison, $1500 for the controller and $2500 to build the Allison and $800 for the converter and you have a hefty investment. The Allisons are a bit overrated IMHO. They aren't that tough out of the box. If you've driven a hot Allison Duramax the first thing you notice is how the engine defuels on full throttle shifts. This is so the clutches don't fry trying to hold the power. With an aftermarket controller you eliminate the WOT defuel and the Allison isn't so tough anymore.
The 47RH is a 727 automatic with an added overdrive section and provisions for lockup. The A518 is nearly the same thing but without lockup. An A518 can easily be made into a 47RH, The case, most of the internals and OD section are pretty much the same. There is no controller for the 47RH. It is entirely hydraulic sans overdrive and lockup. The beauty of the RH dodge transmissions is they incorporated generous pressure test taps into the case. You can very easily take a permanent pressure tap off the governor pressure port and use this pressure to activate adjustable hobbs switches to control OD and LU automatically. It works very well.
The 47RH is a 727 automatic with an added overdrive section and provisions for lockup. The A518 is nearly the same thing but without lockup. An A518 can easily be made into a 47RH, The case, most of the internals and OD section are pretty much the same. There is no controller for the 47RH. It is entirely hydraulic sans overdrive and lockup. The beauty of the RH dodge transmissions is they incorporated generous pressure test taps into the case. You can very easily take a permanent pressure tap off the governor pressure port and use this pressure to activate adjustable hobbs switches to control OD and LU automatically. It works very well.
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ameristar1
The One Blue Thing
Hey Dustin, for a settup like you are talking about, do you have a schematic and part #'s?
How do you set the shift points and lockup points?
How do you set the shift points and lockup points?
averagef250
Full Access Member
The 727 through 47RH governor tap is located at the extreme rear passenger side of the main case towards the top. The pressure tap is designed to put to 1 PSI per MPH of vehicle speed, but in practice it doesn't. Rear axle ratios and increased line pressure from installing a shift kit change the pressure output from the governor tap. The fact remains though that if the transmission is working correctly the governor will raise and lower pressure in exacting prportion to vehicle speed.
Once I've installed a 47RH in a truck and tuned the throttle cable I run a 300 PSI or so rated 1/4" hose from the governor tap into the cab and wire OD and LU to toggle switches also in the cab. I drive the truck, watch the gauge and flip the switches at various throttle position, RPM and loads to get a feel for where the tranny likes OD and LU to be. Once I get a baseline for pressure ranges I buy two hobbs switches to install to do the job automatically. I first install the hobbs in a pressure regulator on an air line to get them adjusted close then install them in the end of the hose with the gauge in the cab and tune them while driving. Once I get them dialed in I install them rigid into a tee in the side of the tranny. Sometimes the switches will shuffle O/C/O/C mounted on the tranny so I'll mount them remotely off a short length of rubber hose and the hose works as a hydraulic accumulator to decrease the hydraulic shock to the switches.
The pinout on the transmission connector is very easy to remember. There are 3 pins. The center pin is +12V, grounding the forward pin locks the TC and grounding the rear pin relieves pressure to the direct drum piston allowing the OD spring to lock the OD clutches.
I usually do not install a kickdown switch, but you easily can if you want to. You can wire it to your liking, the simplest way being to cut the 12V to the center pin past 2/3 or so throttle. I've found an overdrive toggle switch or two on the dash gives better control though. Most of the conversions I do with autos are 12 valves making 600+ lb/ft. An engine with that torque in a <10K pound truck could care less when you shift OD as long as it's above 35MPH or so. Most of the time the TC locking at more than 1/2 throttle is enough to bark the tires.
Also, it's very difficult to tune this setup if you have the stock 2500 RPM governor spring(s). going to 3200 (VE) or 3500-4000 (P7100) gives much better results and acceleration before the TC locks even with an aftermarket low stall TC.
Once I've installed a 47RH in a truck and tuned the throttle cable I run a 300 PSI or so rated 1/4" hose from the governor tap into the cab and wire OD and LU to toggle switches also in the cab. I drive the truck, watch the gauge and flip the switches at various throttle position, RPM and loads to get a feel for where the tranny likes OD and LU to be. Once I get a baseline for pressure ranges I buy two hobbs switches to install to do the job automatically. I first install the hobbs in a pressure regulator on an air line to get them adjusted close then install them in the end of the hose with the gauge in the cab and tune them while driving. Once I get them dialed in I install them rigid into a tee in the side of the tranny. Sometimes the switches will shuffle O/C/O/C mounted on the tranny so I'll mount them remotely off a short length of rubber hose and the hose works as a hydraulic accumulator to decrease the hydraulic shock to the switches.
The pinout on the transmission connector is very easy to remember. There are 3 pins. The center pin is +12V, grounding the forward pin locks the TC and grounding the rear pin relieves pressure to the direct drum piston allowing the OD spring to lock the OD clutches.
I usually do not install a kickdown switch, but you easily can if you want to. You can wire it to your liking, the simplest way being to cut the 12V to the center pin past 2/3 or so throttle. I've found an overdrive toggle switch or two on the dash gives better control though. Most of the conversions I do with autos are 12 valves making 600+ lb/ft. An engine with that torque in a <10K pound truck could care less when you shift OD as long as it's above 35MPH or so. Most of the time the TC locking at more than 1/2 throttle is enough to bark the tires.
Also, it's very difficult to tune this setup if you have the stock 2500 RPM governor spring(s). going to 3200 (VE) or 3500-4000 (P7100) gives much better results and acceleration before the TC locks even with an aftermarket low stall TC.
Mudbillyrednec
Full Access Member
Awsome info....Thanks so very much....
Any Idea of an approx cost on a mild 47RH 2wd trans , for the "avarage" guy ...I know it's a stretch ?
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