Dodge Cummins Diesel Forum - Reply to Topic
98.5-02 Powertrain Discussion of components that are directly involved in the power production and all that is needed to get and keep the truck moving . Engine , Transmission Ect..NO ADVERTISING .

Thread: NV5600 to FSO6406A 6 speed Fuller Reply to Thread
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  Topic Review (Newest First)
01-26-2020 03:40 PM
Tmtbob Why do you need compressed air on a clutch. Are you needing a pto off the tranny?

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01-26-2020 02:17 PM
12vrattlebox I have a 1997 12 valve with a nv4500 and a south bend single disk it’s working fine put a fully splined main shaft and 5th gear retainer it’s about as good as can be. It’s doing fine but I wanna do pdd towing compounds and I know that will probably end its life. Rather than messing around with cryo treated internals and 1.375” input and all that I wanna bite the bullet and get a Eaton FSO8406A or FSO6406A I am in Oklahoma but I’ll be headed to Washington soon. I’m looking for someone to do the installation. I could buy everything that could be anticipated and hand it off to you. I travel in a 40’ 5th wheel so I don’t have a shop to do the work and I’m curious if someone would be interested in this project. Or if you wanna tackle it together I’ve done lots of fabricating and welding I’m certified in tig, mig, stick aluminum stainless carbon all positions most processes any electrical will be easy I’m a licensed Journey electrician in a dozen or so states. I have a flatbed on so one of my underbed boxes I’ll probably turn into an air compressor compartment for the clutch. Let me know if anyone is interested or if you know someone that can do this. I’m very interested in making the switch.
01-09-2020 10:36 PM
NV5600 to FSO6406A 6 speed Fuller

It's nice to hear that there are a few out there that want to install a Fuller trans in their older trucks. With the new trucks, you don't have a choice, you'll have to go with an auto. My truck is nearing the 20 yr old mark, runs as good as it did new, no gear noise in the cab and shifts as smoothly as cutting butter with a hot knife.

A few years ago I changed out the ECM and that alone improved a whole lot of things, especially my fuel mileage. I have about 175,000 on it now. It generally only goes out when it needs to work and and most often it's a heavy load, 25k to 35k.

As to power levels, the truck is absolutely stock except for the transmission. I do believe I'm getting my rated 235 HP. I really don't have any complaints. Truck pulls well uphill and will cruise loaded at 70 and 2400 RPM and if I punch it will do 80. I usually drive at 65 MPH. Only mechanical issue I have is that the turbo is leaking a slight amount of oil into the charge air. No clouds of smoke yet.

Now that I am nearing 74, I won't be buying a new truck anytime soon.
01-02-2020 06:54 PM
NCA Paul
Sounds like the transmission is holding up good. I was curious of the following: How many miles do you have on it? What is your estimated power level? What would you say your average load GCVW is? I am getting the stuff now so I can do this swap also in my 3rd gen.
I will do a build thread when I get everything ready to swap.
Building and machining parts is no problem for me I am fortunate enough to be able to build whatever is necessary.
I really appreciate what you’ve done here
11-16-2019 10:47 AM
Tmtbob Be sure to post some pics of that. Id like to see it

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11-15-2019 11:06 PM
Jwpyle Does anyone know if someone has an Eaton Fuller on a 12v that was swapped into a 69 Ford F-250 Highboy. Im swapping a 5.9 into mine and would like to have the FSO 8406A with it.
09-12-2019 11:52 AM
Dylanss180 I am monitoring it, I have a temp probe in one of the PTO covers. I was towing my RV last week at 75mph in 6th and it was getting warm (220F) and it was around 75 outside. The Eaton Manual says to have it operate 120f above ambient.
09-12-2019 11:42 AM
chansey Dylanss180,

Are you monitoring the oil temp in the tranny and therefore the oil cooler or was it just to add a safety factor? Isn't it nice to get in your truck and not have to worry about what your transmission is going to do.

The Fuller's seem to like hauling and towing and with the Cummins, it's a good match.

I agree that the 2000 and 3000 series Allison trannys are a good option. Even cores are over a $1000 if you can find one. I was watching an auction and two 2500's went for $2750 ea.

09-12-2019 09:14 AM
Dylanss180 Ill report in also. I did my swap a year ago and still no regrets here also. I ended up adding a tranny cooler on mine because I would tow in 6th gear going 75mph for hours on end. Still enjoy the tranny here as well. I was toying with an idea of getting a Dodge 5500 and swap in an allison tranny. Not sure what size but was thinking a 3000 series. I wanted to do an auto for the wife to be able to drive easier.
09-12-2019 05:34 AM
magnum12r That's good to hear, I've been looking at this thread for awhile now, but I'm looking more into an older style 13 speed myself, more of a custom factor for my use but also for great towing performance and reliability. (And I used to drive a 13 speed in a Pete so it's second nature to me.) I have just yet to find the exact model I'm looking for or gathered all the conversion parts. I need to do more model number research checking gear ratios and such, I prefer the ol silver knob Fuller 13's with the 3 position side switch. [emoji41]

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09-12-2019 02:56 AM
chansey Hi all.

Just checking in to see how things are going.

Had 26 telephone poles on my 40 ft trailer this week. Grossing over 30K. That FSO6406A is fantastic. No issues whatsoever, quiet, and no gear rattle. Turned radio off just to enjoy the ride. My truck will be 20 yrs old soon and I'll be 75 after the first of the year.

I'm currently building a 1996 12V VE Cummins that I've already sold. It's destined for a 2004 Chev 4500 with a 1000 Allison.

Picked up another Frito Lay truck (free) with a great running 3.9. Plans are to install it in my 1942 Chev G506.

If you're sitting on the fence contemplating if you should bite the bullet and do a trans conversion, go ahead you won't have any regrets.

Only current fix needed on my truck is the turbo is leaking oil ... need to get it replaced.

08-15-2019 01:24 PM
santino For sale 2006 ram 3500 extended quad cab from texas with 96 12 valve and eaton fuller fs06406a installed in it.... Selling due to fu**** neck n back mint texas ram 3500 dually lone star edition 156,000 orig miles loaded 12 valve p-pump has 130,000 orig miles on it eaton fuller fs6406a has zero 0 miles on just rebuilt done right truck is red with grey power interior clean title i love this truck $14,000.00 o.b.o 313-269-8519 truck is in detroit michigan
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