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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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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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