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Yes, all of the above with the SAE flywheel housing.
SAE #2 gives you the most medium duty transmission choices.

Do a search for all the automotive transmissions that came on the 4BT.

Grigg
 

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If you get a bread van engine with the chevy adapter on the back of it, it would have had a TH400 or a SM465 bolted to the back of it.
 

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Flywheel needs a pilot bearing that matches trans input shaft diameter and machining. Clutch needs to fit input shaft diameter and spline count, release bearing needs to fit input shaft bearing housing, and pressure plate needs to bolt to flywheel. Input shaft length must be correct to get proper depth at flywheel pilot, and must allow proper release bearing ops, and bellhousing has to let everybody play nice together. Bell housing needs to allow using a clutch linkage that works with the release bearing whether mechanical or hydraulic. Ankle bone's connected to the..... etc.
 
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Assuming you would go the SAE route, all the various bits pretty much have to be for SAE setup. Here's an excerpt from one of my posts on another forum regarding a similar question for the IHC 6.9/7.3 IDI engine:


- SAE #2 flywheel housing
- Flywheel specific to SAE spec
- Pilot bearing(fits trans input and flywheel)
- Starter specific to SAE spec
- Clutch specific to SAE spec(and disc to transmission)
- Throwout bearing specific to trans and SAE spec
- SAE #2 clutch cover that works with transmission
- SAE system uses mounts on either side of the flywheel housing vs a single under the transmission


This is a basic list.

Parts come from both engine manufacturer and trans manufacturer, or third party like Phoenix Castings. The SAE system allows each to build to a standard so that the manufacturers don't have to work in concert with one another, just with the standard.

Ken
 

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Discussion Starter · #9 · (Edited)
Okay, but where do I find this information, I have searched on the web and haven't been too successful on finding the information. The SAE info has been very easy to find. What about a bell housing for the RTO-6610 or RTO-610?

Thanks
 

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Find out what the transmission you want was used in. This may involve researching alot or a little I don't know. I found my info via reading and participating in online forums much like this one for many years now. I have tracked down housings and such for various engines and transmissions I want. To do it my way takes time. It's happened over the course of about 8 years now. So if you want something done quickly you're going to go about it differently than me.

Truck scrap yards may yield info and parts. Old brochures and manuals will yield info about what was in what. Online discussions will yield info and sometimes parts, but it takes time. I attained only one part by asking for it in a wanted section. The rest have been found by me knowing what I'm looking for and what it came in etc.

I've found parts by seeing certain parts on ebay and asking the seller about other parts not listed. I found a new starter on ebay because I knew the truck application listed had to be for the starter I wanted. No engine or SAE mentioned so no search for that info would've turned up the auction. I picked up an SAE #2 flywheel housing via ebay because I saw an auction for various engine parts that pointed to an engine with this housing on it being parted out. I inquired and made a deal on it. It wasn't listed.

You're looking for old, used parts. There is no single repository of information for what you are looking for.

You are highly unlikely to search via google or ebay for an SAE cluctch cover for an RTO-6610 and be successful. You need to find out what that trans came in. I'm sure there are multiple makes and models that used this trans. Then search out parts for these trucks. Then ask the folks selling parts for these trucks about the transmissions, etc.

Likewise with the Cummins side of things. It's going to be a Cummins produced SAE flywheel housing and flywheel. Cummins will have parts info for clutches. Really, the only part that may not exist outright is the pilot bearing and that can be dealt with.

I know I'm not really giving you what you want here but I don't have the info you want so I'm relating what I've been doing on a similar note.

Ken
 

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You are trying to make this in to a big deal, and it's not.

I have several Roadranger 6 and 66 series transmissions (RTO-6610). They all come with a SAE #2 clutch housing (it's not called a bell housing). Some have provisions for rear engine / transmission mounts on the clutch housings.

The RT or RTO 6610 or 610 (10 speed) transmissions almost never use a rear transmission mount. The engine will be mounted by the flywheel housing, or on the clutch housing, the engine weight pretty much balances out the transmission weight, and you use a front single engine mount.

You will need a Cummins SAE #2 flywheel housing, with related starter and flywheel.

The transmission bolts right to this, no problems there.

The clutch is a standard Eaton Fuller part, pilot bearings are no problem.
I would recommend the Pull type clutch, as it can be used with a contershaft brake that is nice to have for the unsynchronized transmission. Pull type for a 6xx or 66xx transmission is 1.75" diameter 10 splines. Pull type clutch already has the "throwout bearing" as part of it.

If you do use a push type you need a 1.5" 10 spline input shaft, a new input shaft bearing retainer, throwout bearing, and a countershaft brake (to make up for the lack of clutch brake).

Several different input shafts are available with different pilot diameters, they cost about $65 new and can be changed by removing 4 bolts and two snap rings, really simple.

Grigg
 

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Sounds like you'll need more engine with that many gears. You're looking at in excess of #1200 with just the engine/transmission
 

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83 Chevy K30 Crew Cab Dually
With the equivalent of 1.5 Allison Transmissions (350+ lbs) and a 4BT(Big Block). Your total weight is going to be in the neighborhood of #7500lbs. 105hp is barely going to push that, and it's going to be even slower(Dangerously slow) with the kind of load to justify that big of a transmission. The 6BT would be a better bet in that sort of rig. If 3.9L diesels were practical they'd put that size engine in from the Factory for towing :)
 

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I had until recently a ford 350 with a Detroit Diesel 6V53T (actually with twin turbos).

It had an RTO-610 behind it, and I really liked it. It was great for towing, rpm drop between shifts was about 400 rpms, so I could keep it over 1800 where it had torque and power.

With the 10 speed there was always a gear available that would let me go the speed I wanted with the power available.

For example, I hauled (flat towed) a 7,000 lb plus truck from WA to NY, in addition to about 4,000 lb in the bed of my truck, and 10,000 lb empty weight of my truck, about 21,000 lb total, and I did have the brakes to stop it all.
On I-90 in Idaho going through the mountains near Coeur d'Alene I was in 3rd gear running about 20-25 mph at 2,600 rpm. When I could I would up shift and go a bit faster, but if it got to steep I would down shift again. If I had only a 5 speed the shift up would have been around 800-1000 rpm drop, and taken me out of my power band, the truck would stumble and I would have to try again in an even lower gear than before.
Before you say I had no power, think about this. Through those mountains I was passed (slowly) by a few semi trucks, but I also passed some semi trucks, slowly I'll admit. That Detroit did sound good screaming, pulling, and climbing those mountians... On the down hills I was just slower than most of the trucks, at about 25-30 mph

Until you drive a truck with lots of gears that are closely, and evenly spaced, and easy and quick to shift between them you can't fully appreciate it, and perhaps you won't understand it until then.

So, if you want to use a 4BT to tow with, you will have the best luck with a 10 speed, because you can keep the engine at a speed where it makes power no matter the road speed. You won't have to hold it against the governor just before you up shift to have enough power to keep moving once you do.
 

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Grigg, you have valid points. But what I think what the others are trying to point out is that (depending on what he's planning on towing) the 4bt, no matter the gearing, just doesn't have enough umph to sustain a continuous barage and would be over-worked where it's big brother would be a more suitable choice for the job.

And in my opinion, if you can cram a 6bt into a Wagoneer (search youtube - it's there) you should have no problem getting one into a 77 K30, with room to spare. Remember, it's a Cummins - so you can still source out the same medium duty tranny options if 10 speed is what you really want to do.
 

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Steelhorse,
I agree, more power makes towing more fun, and the truck in question will fit the 5.9, again with a 10 speed, or 13 if you want 3 even slower gears.

But, if towing is the goal, either engine will do the job to a point, top speed will be limited by HP and torque.
So, to make the best of what you have, be it 4 or 6 cylinder, the 10 speed will be great, low rpm drops at shifts is the key.

I was not trying to say that you can easily tow 21,000 lb with just a 10 speed, it takes power, and I imagine if I had a 4BT in the truck I would have been at about 10 mph in 1st or second gear, but it would have done it, really really slow.

If you want to tow with a 4BT, it can be done, just don't set your goals so high. And if you do have high goals, get more power, like an extra two cylinders.

Grigg
 
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