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Hello, been a member for years, read and studied many posts, and have enjoyed the many talented people and their builds/discussions. A little background, my first conversion was a 4bt w/turbo 400 from a ex-Frito-Lay P30 van into a 1980.5 chevy C30 454 w/turbo 475 crew cab dually. This was in mid 90's. The only real improvement was fuel mileage. I then started looking for a 518 transmission from behind a 1st gen dodge. The local wrecking yard had one that needed rebuilt in a 93 d250 standard cab for around $500 or I could buy the whole pickup for $1500, so I bought the whole thing. I rebuilt the tranny in the dodge and drove it for a while. It was so much better than the 4bt. I decided to swap the 5.9 and rebuilt tranny into the dually. I finally found a 47RH and rebuilt it so I could have a lock-up TC. I thought it would be a simple trans swap in the dually, but no, I tried to use the 2nd gen thicker adapter plate but the starter wouldn't fit due to the narrower frame of the chevy, so back to thinner 1st gen adapter plate. I was able to make a spacer to use the 47RH on the thinner plate. I ran that setup in the dually for years. During this timeline I also did a partial rebuild on a 1952 John Deere model R tractor that I would tow with a 20' gooseneck to different EDGTA shows in my area. The 4bt would sure work hard and egt's were high all the time(no after or inter-cooler then). The 5.9 made a big difference. I started to research what kinds of auto-transmissions were available to swap into the dually, from allisons 545, 1545 (lock up version of 545), this was before the 1000's came out, 68re's aisin's, etc. I finally decided to go with a manual transmission swap so I found a RT6610 on eebay. My daily driver was a another 93 d250 club cab that I hit a deer with going to work one morning. I needed a pickup to tide me over ( as the dually was not usable because I had to use the 47RH in the 93 clubcab) so I found a 127k 97 ram 2500 club cab w/NV4500 locally that I currently use. I really like the way it drives and handles. I decided to use the RT6610 in the 97 ram2500 instead of the dually. So I will post more of why I decided this way and some pictures when I figure out how to do so.
 

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Don't know that you'd like the RT6610 with a 6bt. It has no OD gear so you'd be running high RPM when cruising. Makes for terrible fuel mileage. The RTO6610 might be better since it has a .80 OD gear. The NV4500 that was used in those trucks has a .73 OD.
 

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Mack,

I finished this swap last year in my own truck. I got my hands on a RTO6610 though (tag on it states it was originally a RT unit). The gears and spacers need to switch the transmission into an overdrive unit are still available. You can order them from epro gear. I agree with char1355 on the overdrive - you will want it if you are using regular LT tires on the your truck. The overdrive will give change the shift pattern on 4th and 5th gears. You may have already seen it... a link to my swap: Eaton-Fuller RTO-6610 stuffed behind a 7.3 diesel in a 1997 F350

Cj
 

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I have a RTO-610 behind my 4-53T that is labeled RT, so someone converted it in the past. Never know what one can find.

Ed in CO.
 

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Discussion Starter #5
I agree that a RT-6610would not work as well as a RTO-6610, so I bought the K-2019 OD kit and the K-1850 master overhaul kit after a quick inspection with the top cover removed, just to see if there was any major damage. It had the 1.5" input shaft and a counter shaft brake already installed. I completely tore it down this past winter. There were some things wrong with it. In the right side of the transmission case there is a gravity oil feed hole that supply's lube for the reverse idler gear bearing and front of the aux. counter shaft. The factory did not drill it through to the horizontal oil passage. I think because this side of transmission is for the most part submerged in oil is the only reason that it did not do major damage. Also the aux drive gear had heat cracks all over the cone area for the synchro, so I bought an aftermarket one and a new synchro assembly. The aux drive gear had to be ground just a little to get the correct min. of 5 thou. clearance for the reverse gear (had to get different thickness thrust washer also). While the trans. case was empty I also was able to go to a friends shop and use his lathe and mill to machine the adapter plates to go between the trans. and the bellhousing. He also had a nice press that I used to remove and reinstall the gears on counter-shafts.
The attachment is a picture of a excel worksheet I used to see what mph is in different gears of both RTO and NV4500. The NV4500 is with 3.54 ratio axle, and the RTO6610 is with 3.31 ratio axle.
 

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Discussion Starter #7
Pretty even comparison. Good engineering and good results !
I like the way it runs at 65, the engine around 1900, I'm 150-175 rpm above peak torque. This with a loaded trailer. I've had too many trailer tires blow out to run much faster. I go faster with unloaded trailer.
 

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Here are some photo's of the trans gears and aux section. The second photo shows the aux gearing, the aux drive gear had cracks on the synchronizer face so I replace it and installed new synchro. assembly.
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Yep I recognize all those gears! I didn't have to take my main box apart though as the overdrive swap had already been done. The output shaft is a serious chunk of steel.

Cj
 

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Interesting rpm/mph, I run around 2000/2020 at 65 by the GPS. 3.32 final gear and 215/85 16 tyres. May need to recheck the tacho for accuracy.
 

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Discussion Starter #11
Yep I recognize all those gears! I didn't have to take my main box apart though as the overdrive swap had already been done. The output shaft is a serious chunk of steel.

Cj
I enjoyed doing the overdrive conversion, granted it was slow going because I was constantly referring to the service and parts manual and it was my first time working on this style of transmission. This was a lot harder than the old Muncie 4 speeds from the early 60's GM cars. I really liked the conversion you did on your Ford.
 

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Discussion Starter #12
Interesting rpm/mph, I run around 2000/2020 at 65 by the GPS. 3.32 final gear and 215/85 16 tyres. May need to recheck the tacho for accuracy.
I haven't tried the GPS so I don't know how it would compare to real world numbers. I do know that my speedo was reading 2 mph faster then the data pulled from the OBD II. I bought a digital speed sensor to go onto the old cable drive on the fuller. I will need to buy digital signal adapter to modify the pulse count per mile. I should be able to fine tune my factory speedo then.
 

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I run a VDO electronic speedo with a VDO sender and have the speedo 1KPH high, Basically needle width. Tacho also a VDO with a flywheel pickup. Both tuneable.
Cheers Steve
 

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Discussion Starter #14
I run a VDO electronic speedo with a VDO sender and have the speedo 1KPH high, Basically needle width. Tacho also a VDO with a flywheel pickup. Both tuneable.
Cheers Steve
Having the ability to tune the gauges is a big plus, especially if your projects allow for retrofitting modern gauges into dash panel. I once had a 56 gmc 1/2 ton pickup that the dash had all round gauges, however the same year of chevy pickup had a completely different style of dash.
 

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Discussion Starter #15
I started the fuller conversion on May 4th. Pulled seats out and rolled carpet back. Photo shows NV4500 still in.
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NV4500 pulled in this photo with rough outline where the trans tunnel will be cut.
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Drivers side cut line.
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This shows the tunnel cut out. I removed adapter plate and cleaned it. Installed new rear main seal and reinstalled adapter plate.
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Here I have temporally installed fuller trans.,(no flywheel etc.). I will upload photo's of the trans to flywheel housing adapter plates I machined at a later date.
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This photo shows the trans resting on two 2x4's' which is a little over 3 inches / 75 mm on top of stock crossmember. Before I removed the NV 4500 I measured to the center of output shaft from each frame rail and also to the trans tunnel. When the fuller was installed I measured to the center of shaft like on the nv 4500 and I am within 1/8 inch / 3.17 mm, side to side and less than 1/4 inch / 6.3 mm, on vertical(rto 6610 is 6 inch / 152 mm, longer than nv 4500). I'm hoping the new driveline will not vibrate.
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Discussion Starter #16
Just some more photo's
This is of the right side. The trans-tunnel still needs to be trimmed some more for clearance for the slave valve.

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This is of the 18ga sheet metal with the cutout for the shift tower. I made it larger to give access to the reverse and neutral switches.
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Drivers side showing clearance. The sheet metal is resting on 1 x 4, (25 x 100 mm) just to see if it looks ok.
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This is on passenger side.
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This is after a week. I am going to make a panel to access the area around the A-5000 valve as there is no room at all to get to the slave valve if it or the airlines need work, and I don't feel like dropping the trans to get to it.
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Here is a side view of same. There will be less than an inch (25 mm) of clearance when the tunnel is welded back on.
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Doing sheet metal work is eating my lunch, it seems to take forever to get any progress done.
 

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Discussion Starter #18
Decided to take a break from sheet metal work. My nephew helped me turn the truck around so rear was towards the door to make it easier to change out axle. Removed the 3.54 axle and installed the 3.31 axle. The 3.54 axle is a one wheel wonder, so last winter I decided it would be easier to go to the wrecking yard and purchase another axle. They were able to get me a 3.54 Dana 80 that had factory installed spicer traclok. It was from a 98 ram 2500 so it still has the drum brakes (which I prefer). I installed the 3.31 gear set, put all new shoes, drums, brake lines, cables, etc., on. I also modified the hubs with a 1/4" socket pipe plug to make it easier to drain and fill with fresh lube when needed.
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On a side note, I remember one time at work a mechanic replaced the hub seals on a gm pickup and he was called off the job. When he got back, he added the 90 w gear lube but forgot to make sure the bearings were prelubed. It didn't get very far down the road before all the bearings had spun on the spindles. That was one expensive call back.

Picked up the new drive line. It is 4" (100 mm) tube with 1550 u-joints.
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Here is the trans mount, it bolts up where the main and aux transmission cases bolt together. I am still able to use the stock rubber isolator and crossmember.
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A little back story on why I chose to make the trans to bell housing adapters the way I did. The RTO-6610 input shaft sticks out from trans case about 10.5" (267 mm). I also wanted as much room as I could get inside the bell housing in case I wanted or need to get a double-disc clutch setup in the future. I decided that by using the 2 gen engine adapter plate and a 1 gen (getrag) bell housing I could gain an extra 2.25" (57 mm) of space. Since the getrag trans had a 1.25" (32 mm) input shaft, the clutch fork and release bearing would not work with the fuller. I got a T827 clutch fork for a 90's C60 from Fort Wayne Clutch and Driveline (no affiliation), and a N1456 release bearing. I still have to modify the clutch fork to work correctly in the getrag bell housing. I purchased a 1' x 2' x 1.25" thick(305 x 610 x 32 mm) aluminium plate from eebay to make the 2 piece trans to bell housing adapter.
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I drilled and tapped extra holes in the getrag bell housing.
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This bolts on the bell housing.
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Here is the other plate on the trans.
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I had to have the flywheel bored out to fit a ball bearing pilot bearing, I'll try to remember to get the bearing size and post it.

Regarding the getrag bell housing I think it was machined incorrectly because I put new alignment bushings in the engine adapter plate and checked run-out, I had over 0.020" (0.5 mm). Fuller recommends no more than 0.008" (0.02 mm). I used some offset bushings to bring it in under 0.005" (0.127 mm). So I am hoping that with everything bolted up it will stay within specs.
 

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Discussion Starter #20
The trans came with the counter shaft brake. I figured the csb was the least painful option,lol. I had to remove the exhaust pipe from the turbo to the cat converter to gain better access to where I needed to do some welding. What a pain, two chain falls and a victor wrench to heat up the joint red hot, it finally pulled apart, those dang exhaust clamps sure do crimp the pipe.

Well, back to the dreaded sheet metal work. Part of the new tunnel was stitch welded in.
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Part lap joint, part butt joint. When we bought the mig machine back in the 80's we didn't know enough to spec out the machine with the options to use different sizes of wire (and I don't recall the salesperson pointing out that to use different size wire you need the correct drive rolls) so all we got were for .035 and .045. Well here I am with a obsolete but very low hours, no parts available, (manufacture being sold several times) machine running the .035 wire to weld this thin sheet metal. That's why there are blowholes. Some day I will find the .023/.030 size rolls or adapt the drive mechanism from a modern machine.
 
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