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NV5600 to FSO6406A 6 speed Fuller

1M views 2K replies 248 participants last post by  gbcummin 
#1 · (Edited)
2001 Dodge 3500, 112,000 mi, 5.9 Cummins, 4X 4, Long Bed with NV5600 6 speed transmission. Just went out again for the 3rd time. Failures were at 82,000, 97,000 and now at 112,000. Had regular dealer service. Use it to haul a 40' gooseneck and a Case 1155E loader tipping the scales at 25,000 lbs.

Parts are really hard to find. Last time I had to buy a core for $500 just to get parts for the rebuild by a heavy truck tranny shop. Problem seems to be in the 5-6 gear section with seized bearings.

Spoke with a rebuild shop in Ohio and they have started drilling lube holes in the case and bearing shell and claim they have not had any failures since they started. Anyone have experience with this procedure???

I am changing the NV5600 out for a Fuller FSO-6406A. It has a 660 HP rating with 6th OD at .78. These ratings are close to that of the NV5600.

This is not new or innovative. The Freightliner FL 70 has used the FS6406 6 speed since '93 and Ford has used Fuller's with Cummins on the F650 and F750 since 2003.

Since Fuller never has had a married transfer case, the transfer case would have to be divorced. Need to find the correct clutch set up that is used with the medium duty truck. Would need a #2 SAE flywheel housing and 1-3/4" clutch.

Parts are readily availabe for Fuller and never have to worry about synthetic oils--should be good for 500k miles or more.

Local trans shop has a NV5600 for $1000. Needs output shaft and bearing. Synchros and all gears look good. Mine will be available as soon as I complete the change-over. I suppose someone will want pictures and part numbers.
 
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#442 ·
B700, so even if it is the 5306 you don't think I should keep it, or only lose it if it is the 5106?

As for the shift rails and the like I think the difference is in the cover, it has a mechanism for the 5-6 shift rail to pivot again, and move opposite what you would normally see. It may be able to be added onto other lids, but it looks like a mechanism in the lid near where the linkage meets the fork. Here is where I am seeing all the schematics.
http://www.inforanger.roadranger.com/epc/index.asp?modelID=544&groupID=566

It has all the medium duty transmission parts, and their schematic, if you look up the FS6406, and the FSO6406, then compare shift lids it is right there.

Chris
 
#443 ·
B700, so even if it is the 5306 you don't think I should keep it, or only lose it if it is the 5106?

As for the shift rails and the like I think the difference is in the cover, it has a mechanism for the 5-6 shift rail to pivot again, and move opposite what you would normally see. It may be able to be added onto other lids, but it looks like a mechanism in the lid near where the linkage meets the fork. Here is where I am seeing all the schematics.
Eaton Inforanger

It has all the medium duty transmission parts, and their schematic, if you look up the FS6406, and the FSO6406, then compare shift lids it is right there.

Chris
Talk to a mechanic who has built a 5306 and a 6406 and find out if the gears are interchangeable..They are 2 series for a reason, better synchros for sure. I am not a mechanic. I will be talking to a rebuild shop or more likely Eaton to find out about the shift linkage on the overdrive. It seems lots of parts are usable from series to series but have different numbers (may be more tempered?) The FSO 5-6 shift fork seems to be shorter, with the block above it. I see about 4 different parts comparing the FS to the FSO.
I do not see Eaton manufacturing a different shift tower for 1 model in a line. Gear shift levers and their housings are interchangeable on several models going back as much as 20-30 years. Clark will fit in an Eaton in some cases.. This exercise is like cutting wood, except, you ask questions and ask more and keep asking until everything is in place an then you go in.
 
#444 ·
If the medium duty is like the HD line of trannies then the difference is in the lid. On HD models you can pretty much stick any tower on any transmission. The main concern is transmission shift tower hieghts matching the lever that are used.
 
#446 ·
If you are still interested try contacting Abros . com. I have ordered from them and seem top knotch. They will save you atleast $50 over that qoute based on the couple of numbers I ran.
 
#447 ·
I tried to order my gears from a bros and they never emailed me back about the order I tried twice. but global drivetrain supply responded quicklly and they have distributors all over the place.
 
#448 ·
Chris, I called and got right through both times I ordered from them. Hooked me up with some used parts for a good price along with my new parts. Sounds like email is the wrong way to communicate with them.
 
#449 ·
I ordered off their website, they have a nice parts search to compare prices though
 
#450 ·
fuller fs6206

Hi i saw that people don't like that transmission because it's not an overdrive.

It has 6th gear that's 1 :1 the truck has 22.5 inch wheels and the rear diff is 4.10



if i put it in my pick up it has 16" in tires 285/75-16. and 3.73 gears


How do I know if it will rev too high or will be good??


Can the 6th gear be changed in a 6206??
 
#452 ·
quote " spoke with Scott at New Mexico Gear and Clutch. His only caution was to watch the direct output drive ratio to the rear gearing. For example, if you use a straight 6 speed with 4.10 gears you will be at 2200-2400 RPM and max at 55-58 MPH. The the 6 speed OD (.73 X 4.10=2.993) gives us a effective high speed ratio of 2.993. "

I don't know if tires (22.5???)matter but I bought a bus and it has the fs6206 in it and it is a 6 speed non overdrive. the rear is 4.10. I was doing 75 on the interstate with no problem. could have went faster. figured it would have a governor being a school bus and all.
 
#453 ·
If your going to swap into a complete truck just drive around in direct or not od and you decide. I know i sure need od in my truck stock tire size with 3.55 gears 2100rpm @ 65 is perfect
 
#454 ·
chris will a smaller tire make final drive higher or lower ratio?? if it's 4.10 with those big school bus wheels and i go to a 16 inch??? will it rev and drag ??

Would a smaller tire be better fuel economy?? or would rpms be too high??

I don't know anout this subject.

Also someone told me that the pump on the bus and the dodge pick up are different and won't interchange.
 
#455 ·
A smaller tire is equivalent to a lower (numerically higher) gear.

I have 37" tires on my truck with 3.42 gears and an SM465 trans with a 1:1 high gear (no OD). I turn 2000RPM at 65MPH with that combo. If your truck has tall enough tires and tall enough gears a non-OD trans is fine. In most cases that isn't possible, so an OD trans will be needed.
 
#458 ·
Yes but there are practical limits. D60 front axles have a minimum of 3.55. I'm pretty sure the tallest gear for an 80 or an AAM 11.5 is 3.73. Unless you have really tall tires you're going to need OD. I simply mentioned it because some guys run really tall tires, like 39's on 22.5" wheels. Even with 37's and 3.42's I turn over 2300RPM at 75MPH, which burns a lot of fuel. Even 2k RPM at 65 isn't the best for fuel economy.

The tallest gear I can get for a 14bff is 3.21, which would have me turning 1900RPM at 65MPH and just under 2200 at 75. If I swap to a 6 speed Allison and 4.56 axle gears I will only turn 1670RPM at 65 and 1925 at 75MPH. In addition I will have two useable downshifts at 65MPH: 5th gear at that speed will turn 1910RPM and 4th will turn a hair under 2700RPM. If kept my manual and swapped in a D61 and D70 with 3.07's I would still turn more RPM than the Ally with 4.56's, and I still wouldn't have a useable downshift. So, with axle gearing limitations being what they are, an OD trans is really the only practical choice.
 
#457 ·
Run out of money. Have trans and o/d gears.... B700 Cummins needed Dodge pulley and manifold and oil tube. Using 7.3 rad and intercooler. .... using bus flywheel housing and a bell-housing off Freightliner (could use Bus B-H but hydraulics are simpler) Have 99 7.3L not yet sure where everything will sit. Have to buy a slave, fork and clutch and pay the guy to do it.
ZF6 and 7.3 will be sold after. Both in very good shape. 7.3 needs oil pan and #1 & #2 injectors. I want a gearbox that fits behind a Cummins and I need o/d otherwise I will be at the top if not beyond the power curve. To do this right I would need to spend $300.(parts) to change tower and may even need to change the tower case itself. Just going ahead and live with inverted 5-6 as 6-5 for now.
Make Absolutely sure that dowell pin has not fallen and damaged the front gears.
If you screw around with an earlier FS 6 version, be prepared for synchronizer differences. That seems to be the biggest dif. With smaller wheels you will need o/d. Right now I am putting the parts together and having the Cummins prepared to go in. When I have it in, I will be able to give you real insight into this swap.
 
#459 · (Edited)
thanks people.




I didn't go under it but i'm sure the bus clutch pedal is cable operated???




When you say "tube" do you mean dipstick tube or oil pickup tube??? Does it need different oil pan too??



So is this a Sae 2 or Sae 3 tranny adapter?? Are the clutch flywheel,and or tranny adapter worth any money $$$$$ ?????





I looked online and there are no fso 8206 or 6206 around. I find that hard to believe. What truck did these FSO's come in???

I might sell this engine money is tight now. But not sure.


cummins :: MVI_0705.mp4 video by mrblonde108 - Photobucket
 
#460 ·
I am getting the transmission I was talking about, we will see if it is one that can be upgraded to FSO status, if not, I will use it until I can find another, and then sell it. If it can, I am still going to use it as I have a show then 3rd weekend in Aug, and need a transmission in the truck by then.

I have found the gears I need for around $100-120 a piece, except the input. If anyone knows a good place to find the 4 gears needed to convert a FS into FSO for cheaper please let me know. I am hoping I can get the gears in as soon as I get back from the show.

Any other info or tips on the installation would be great! I am excited to get a transmission that can hold this engine.

Chris
 
#461 ·
You need a good bearing puller and a big press to change countershaft gears. if you plan on running the transmission for a while get a basic rebuild kit and put all new bearings in.
4304541 $125.00
4304542 $99.00
4304540 $135.00
4304543 $90.00
these are the part numbers and prices(from feb. of this year, may have changed) from global drivetrain supply
 
#465 · (Edited)
Cummins to Ford 7.3 Powerstroke ZF 6spd

You do not need to buy a different starter for these plates as they are designed to use the Dodge application Cummins starter that came on your Cummins engine.

ford cummins sells for $800 with the spacer plate.


How much is a SAE2 and 14" Flywheel worth??? I might sell mine and just go with the zf.
 
#466 ·
I want to ask as many of you as possible: What RPM do you turn in your highest gear at 65MPH?

Right now I turn 2K, which works really well but I am wondering about keeping the manual and using a bit taller gear to drop another 100RPM...
 
#468 · (Edited)
Well, I sold my Ally to a buddy for his Cummins project (12V into a late 80's crew cab dually), so just for grins I checked out Craigslist for any cheap Fullers. Lo and behold a guy has a FS6306A for sale, cheap. Complete with shifter, bell, everything. HMMM....

So, I did some research. Apparently, the FS64xx's have better syncros than the 63xx series. I wondered if they were interchangeable, so I started poking around and i found that they are. This is good news for myself and anyone else who finds a smoking deal on a 6306A: The syncros listed in the parts sheet are the same as those for the 6406A. In other words, the newer 64xx syncros supersede the older original 63xx syncros, so if it needs a rebuild you will automatically be upgrading it to a 64xx.

One other thing struck me as odd. I compared all the major parts between the FSO6406A and FSO8406A and I could find no difference in part numbers. The case, shafts, gears, syncros, and syncro hubs are the same, as are the input shafts. So, why they give the 8406 a higher torque rating is beyond me :confused013:

Anyway, armed with this info Im gonna pull the trigger on this 6306. I won't even switch it to OD: with 3.42's's I will only turn 2020RPM at 65MPH, and cruising in direct creates less heat and burns less fuel than the same speed and RPM in OD. I could go with 3.21's and drop down to 1895 RPM, which would be the same as 4.10's with the .78 OD cog. If I swap in the 1-1/2" push tupe input and its matching retainer and mate it to an NV4500 bell it will bolt right up and let me use my existing South Bend clutch. not to mention I wont have to hack my firewall to fit an SAE housing.

I will need to respline the mainshaft to 32 spline tho.... or do an adapter like chansey is doing. No biggie since I have that capability at my disposal :grd:

EDIT: Well, I went to check out the trans. I have never seen one of these up close - they are friggin HUGE compared to my little 465. The model is an FS5306X. I called up the Roadranger help line and asked them what an "x" model is. Their answer was that it is a 6306A exchange unit, probably a reman. Depending on its age it may have the 6406 syncros in it. Hopefully it doesn't shift like . I paid $600 for it, which seemed like a decent deal. Truck yards around here want at least twice that for a beater, and this one looks to be in good shape. Here's a crappy pic of it:



I pulled the PTO cover and saw no issues, as much as I could see anyway. It had some strange bluish colored synthetic oil in it. The oil smells like Redline MT90, but its not the right color.

i am probably going to pull the mainshaft assembly, disassemble it. and respline the shaft to mate to my t-case. Seems to be a cleaner option, not to mention shorter.
 
#469 ·
Well, I sold my Ally to a buddy for his Cummins project (12V into a late 80's crew cab dually), so just for grins I checked out Craigslist for any cheap Fullers. Lo and behold a guy has a FS6306A for sale, cheap. Complete with shifter, bell, everything. HMMM....

So, I did some research. Apparently, the FS64xx's have better syncros than the 63xx series. I wondered if they were interchangeable, so I started poking around and i found that they are. This is good news for myself and anyone else who finds a smoking deal on a 6306A: The syncros listed in the parts sheet are the same as those for the 6406A. In other words, the newer 64xx syncros supersede the older original 63xx syncros, so if it needs a rebuild you will automatically be upgrading it to a 64xx.

One other thing struck me as odd. I compared all the major parts between the FSO6406A and FSO8406A and I could find no difference in part numbers. The case, shafts, gears, syncros, and syncro hubs are the same, as are the input shafts. So, why they give the 8406 a higher torque rating is beyond me :confused013:

Anyway, armed with this info Im gonna pull the trigger on this 6306. I won't even switch it to OD: with 3.42's's I will only turn 2020RPM at 65MPH, and cruising in direct creates less heat and burns less fuel than the same speed and RPM in OD. I could go with 3.21's and drop down to 1895 RPM, which would be the same as 4.10's with the .78 OD cog. If I swap in the 1-1/2" push tupe input and its matching retainer and mate it to an NV4500 bell it will bolt right up and let me use my existing South Bend clutch. not to mention I wont have to hack my firewall to fit an SAE housing.

I will need to respline the mainshaft to 32 spline tho.... or do an adapter like chansey is doing. No biggie since I have that capability at my disposal :grd:
My 7.3, 3.73, 235/85R runs 2500 in 5th and 1800 in 6 O/D but I sit @ 1500 in 6 O/D @50MPH most of the time to save fuel. The 7.3 has a very wide power curve but all the info on the Cummins indicates a much smaller curve.
I am interested in how this will sit in the F250. I hope I do not have to mess with the firewall. From all info it looks like it will fit. I am getting closer to getting this in. My Fuller has been torn apart and I am told it is in excellent shape and ready for the changing of the gears to O/D.
 
#470 ·
I dunno... SAE #2 housings are BIG. I am going to look into adapting it to an NV4500 bell like I did with my 465. its not gonna be as easy because this trans is so friggin big, but I think it's doable. Also, it looks like all the 14" pull clutches all use ceramic pads, which Im afraid will be grabby in my light truck. My SB ConO is VERY smooth, and its already paid for :D

This does mean I will have to swap in a 1.5" push-type input shaft and it's associated retainer in order to match my clutch and be the proper length. No biggie.
 
#471 ·
Max, I don't think that Eaton has an input anywhere near the size of the one you are using. As for the size of the #2 bell, yeah it is big but it can be made to fit pretty easy. What you may find difficult is getting the proper depth to the pilot bearing, and the rest as the inputs are very long on these transmissions.

Either way, best of luck to you, the more people running these things the more info we will have.

As for me, I got my transmission today. It is a FS 5306 as I hoped. OHH YEAH!!! It's a MONSTER. I had no idea it was this big. Cannot wait to get it in. I wish I could find someone parting out an FSO that I could get the OD gears for a song as well but this will do for now!

Oh, just a quick question, what is everyone doing for mating to this U-joint? It's enormous and I'm just wondering what to do about it.

Chris
 
#472 ·
Max, I don't think that Eaton has an input anywhere near the size of the one you are using. As for the size of the #2 bell, yeah it is big but it can be made to fit pretty easy. What you may find difficult is getting the proper depth to the pilot bearing, and the rest as the inputs are very long on these transmissions.
Remember, I don't have a Dodge. This is going in a 73-87 body style Chevy K5 Blazer, and when I got my Cummins it had an SAE #2 housing on it. I looked into fitting it, but it would have needed massive firewall surgery. The Dodge adapter and NV4500 bell needed a 1" body lift in order to have enough clearance without the engine sitting too low or too far forward. In order to get an SAE #2 housing in there I would have to remove a substantial portion of my firewall and lose my interior HVAC boxes. Then there is still the concern of overclutching the trans - the 14" clutches are designed for trucks that weigh more unloaded than my GCW towing the heaviest load I ever plan to tow. It is pretty much guaranteed that they would suck in a truck as light as mine. I think this is something that many potential swappers overlook, especially if the rig is going to be daily driven unloaded.

I did some research on the input shaft situation, and I will try to summarize what I have learned. I have seen these transmissions with 1-1/2" 10 spline inputs, so I knew they exist. What I found is that there are no fewer than seven different input shafts available for the 5x06, 6x06, 8x06 series.

In the PDF referenced by that link you can scroll to page 3 and look under FS-5306/6306 you will see what I am referring to. This is an older PDF so the newer transmissions aren't listed, but I already know from my research that the inputs interchange between the FS5306, 5406, 6306, 6406, and 8406. Anyway, part # 4301408 is a 1.5" 10 spline shaft with a 25mm pilot, 8.6" overall length from the front face of the trans to the pilot tip, and 2.63" of useable spline. For comparison, we can look at this pic of my 465 with the 1.5" input:



The black line on the pilot indicates how far it sits inside the pilot bearing. Two things to note: This shaft is 8" long vs 8.6" for the Fuller shaft, and the pilot is 1" in length vs .75" for the Fuller shaft. So, the trans needs to set back .60"+.25"=.85". In other words, a spacer approx. 7/8" thick is needed between the NV4500 bell and the Fuller trans. An index lip is needed to locate to the bore in the NV bell, so a piece of aluminum 1.25" thick machined down to the proper dimensions with mounting holes for the bell and trans will make a nice adapter. The corresponding bearing retainer with a sleeve for the TO bearing is part # 3316313. The bearing part numbers listed in the old PDf are incorrect. The proper bearings are part #'s 5202047 (bearing) and 711123 (race). The price from Six States came out to $500 for all of the parts (price is for genuine Eaton Fuller parts - I didn't bother pricing aftermarket rubbish). The only downside to this arrangement is that it is only available for the FS series. FSO inputs are only available in 1.75" BUT.... I have had excellent success in annealing, resplining, and re-carburizing similar parts. If done properly there is no drawbacks, and it would allow a person to turn a 1.75" FSO shaft into a 1.5" push type FSO shaft.

Here's pics of the NV4500 bell sitting in the approx. location where it would mount to the trans:











Just for reference, here is what the 1.5" shaft with the fork and TO bearing will look like in the bell:



I have carefully gone over this plan and there are no show stoppers. I also have the advantage of knowing that the 1.5" shaft and clutch setup with the NV4500 bell works since I have been driving it for over a year now. As long as the Fuller shaft has the same stickout as the 465 when I'm done it will bolt right up.

I should point out that the clutch I have is a South Bend Con-O. It is a 13" high performance clutch, the same in fact as South Bend sells for use with the NV4500, 5600, and G56, except with a 1.5" hub and 25mm pilot bearing. As it turns out, 13" push type clutches are common in smaller MD trucks, so there are off the shelf clutches available. Valeo lists dozens for apps ranging from big block powered trucks to DMax, Cummins, and Cat powered trucks. These clutches are used in SAE #2, SAE #3, and non-SAE housings, and are designed for lower weight class trucks (i.e. Kodiaks, TopKicks, F-550, F-650, etc.). For the SAE Housings, Eaton lists 2 different length SAE #2 bellhousings - 6.625" long and 4.75" long. The longer housings are apparently used for pull type clutches (and are the standard housing), while the short housings are for push type clutches. They also list a short cast iron SAE #3 housing for the 4205, but since the 4xxx have the exact same bolt face and bearing retainer diameter and call for the same SAE #2 bellhousing part numbers as the 5xxx, 6xxx, and 8xxx series, then it is obvious that a person could run this bellhousing on the 6 speeds as well. This would allow a person to use an SAE #3 flywheel housing with a 13" clutch rather than the #2 and 14" clutch, which would allow for easier fitment in many chassis (although it is still bulkier than the Dodge setup).

Anyway, hopefully that all made sense. I am going to go ahead and order the parts to convert mine over to the short 1.5" push shaft. For those who think it's a downgrade, keep in mind that the shafts in the factory 6 speeds are only 1-3/8", and only really high HP sled pullers break them. Unless you're getting into the 1000+HP range and sled pulling the 1.5" shaft isn't going to be a weak point.

Either way, best of luck to you, the more people running these things the more info we will have.
I want to try to make some turn-key parts for people doing these conversions. Unfortunately, I don't see the NV4500 bell adapter being too popular since most guys want OD, and the FSO's are all long 1.75" input shafts. I would respline and re-heat-treat stock shafts, but it would add at least $300 to the price...

As for me, I got my transmission today. It is a FS 5306 as I hoped. OHH YEAH!!! It's a MONSTER. I had no idea it was this big. Cannot wait to get it in. I wish I could find someone parting out an FSO that I could get the OD gears for a song as well but this will do for now!
You won't ever find someone parting one out. They are worth too much as a core if they aren't broken. What axles are you running? Some axles can take taller gears. The GM 14b can take 3.21's, which give the same cruise RPM with a direct drive trans as 4.10's with an OD trans.

Oh, just a quick question, what is everyone doing for mating to this U-joint? It's enormous and I'm just wondering what to do about it.

Chris
Easies thing would be to have that size yoke put on your driveshaft so you can run the big- u-joint :thumbsup:
 
#474 ·
Yup, you're pretty much gonna need OD unless you run 40" tires.

I ordered the 1.5" shaft, bearing cover, bearing, race, seal, and gasket for mine today. All brand new genuine Fuller parts came out to $530, so I can imagine what an input shaft and 3 gears would run :$:
 
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