[cjfisher]

A dual disk is feasible if memory serves me. I believe there is a dual disk setup that is capable of being mounted to a flat flywheel. There is also a well/pot style flywheel (though I not sure if they were made to fit the 7.3L diesel) out there as well. The bellhousing can fit either style of flywheel/clutch. I do have a clutch brake (usually used with a pull style clutch) which mounts on and is keyed to the input shaft between the transmission and throwout bearing. When I start out (the only time you use this is at a stop) I push the clutch all the way in which squeezes the brake between the throwout bearing and transmission and bring the input shaft to a halt. Once the input shaft is stopped I can then put the truck in gear and get moving. There is also a counter shaft brake that does the same thing (optional for pull style clutches and required for a push style clutch) which is just a soft piece of metal on the end of a piston that rubs against the counter shaft aux. output gear.

Cj

 

[Jacobpowerstroke97]

I sure appreciate you taking the time to answer these questions. I guess my next step is to get me a rto9513 on the way. I've sourced a few and those being sae#2 bellhousing but not sure if they or pull or push type. I have heard that the rto9513's are pull type but I'm not 100% persuaded that they are. Maybe someone with eaton fuller experience would know more. And I will add pics of the build as I begin the process. I'm sure I'll be picking your brain often as I begin the process I'm still not 100% sure on how you got your slave cylinder to work but that's a hurdle in the future. Right now is sourcing the rto9513 and getting it on its way. I've done sourced the t444e flywheel and flywheel housing. I'm fairly persuaded on doing a 2 or 3 inch body lift. But I believe I will square tube the bed mounts I have read the bed gets squirrelly if your hauling loads in it with the lift mounts in place.

 

[damarble]

All #2 housings should be able to hold a dual disc. But keep in mind a dual disc rated at 1400lb is figured to pull much more weight that a pickup can safely do. I went round and round with this in my head and finally decided a 800lb single disc will have better manners for my application (800-1000 lb/ft DT360 in a F350).

 

[Jacobpowerstroke97]

I betwixt between the two cause I did want to bump my hp and torque up some which is a reason to going with the eaton trans cause it will live with anything that a 7.3 powerstroke can muster to throw at it I'm persuaded lol. I know the 9513 is rated for 950ft tq but I'm sure itd stand more. I've heard guys running 400hp cats in front of them no problem. Of course I don't intend exceeding 800 ft tq

 

[Blackduck596]

On the Ford 10.25 the spec's I found were 8300 Ft/Lb maximum with 2000 ft/lb continuous, not sure were I found this.
Not hard to get that maximum torque at the final drive with the RR gearing. By memory I am over in the first 3 or 4 gears.
Cheers Steve

 

[cjfisher]

Steve,

How are you down under with the virus mania? I found the torque info for the Sterling axles here: Ford 10.25" / 10.5" Axle Parts, Gears, and Upgrades They also list the Dana 70 as 4663 Ft-lb max and 2000 Ft-lb continuous. The Dana 80 from that same site is listed at 10000 Ft-lb max and 2500 Ft-lb continuous. And the Dana 60 is listed as 5550 Ft-lb max and 1500 Ft-lb continuous. I think the listing for the Sterling 10.5 might be a little too high for max torque while the Dana 70 has been shorted a bit on the torque rating.

Cj

 

[Blackduck596]

Cj. All good info.
The only thing I would like is to find a set of those 3:08 Unicorn gears. Currently running 3:32 but would still like to drop cruising RPM. Do have a Joey (Brownie) box but really don't want the hassle of installing it.
On the Wuflu, my State has closed its border/s to the rest of Australia and the World and we have internal isolated areas so you cannot move around the State. But infection wise we are doing very well.
Cheers Steve

 

[cjfisher]

Hey CJ. I just started a new swap yesterday, DT360 and Spicer Eso 77-speed into a 97 OBS CCLB, and currently looking over and planning out each system. One concern was clutch actuation. I read through your Eaton RTO thread (super awesome, great work!) and saw you used the stock clutch MC which is super cool. What I'm hoping is that our clutch setup requires similar throw so we will be able to do a similar setup with the SD 7.3 slave cyl like you did. Sorry for the ramble, just wanted to provide some background. Anyways, question, how did you go about a clutch hose/line? I did not think the Ford clutch hydraulics were able to be separated and came pre-bled.

Nice! Where'd you find your DT360? I thought about using a Spicer ESO 7 speed in my truck. It is a Looooong transmission with all those gears in a row though. The RTO was a lot more compact, but comes with the downside that it is non syncroed - which has taken me a bit to learn how to drive again. Measure closely as you may need to do more mods on the transmission tunnel. Is your truck a 4x4? The ESO may present some challenges if you wish to marry the transfer case back up (I think it uses a taper bearing on the output shaft which requires a preload that is supplied by the nut securing the knuckle to the output shaft). On my clutch setup.. I did use the stock setup and it is a little touchy in my case as I didn't buy a self adjusting clutch and I have a clutch brake to help to get the transmission in gear at stop lights. As the ESO is syncroed you won't need the clutch brake to get moving so you'll have more flexibility in the clutch adjustment area. If you use a pull style clutch (most common setup in the Medium Duty truck world) the throws should be similar as the bell housings are standardized. The SD slave is much closer in diameter to the original master so I could get a longer travel out of it which changed the pivot point on my throwout arm. The SD and OBS clutch kits are available that are all put together and bled. However, the parts can be disconnected - there are pinned connections with seals that allow you to separate the pieces. So I used my original master, and hydraulic lines (which I re-bent to fit better), which are then connected to the SD slave.

Cj

 

[cruisermatt]

Is your truck a 4x4?

Thank you. I wasn't... but it is now we'll be doing a divorced setup, 205 most likely

 

[cjfisher]

Definitely need a smaller bore master cylinder.
For those with external cylinders and air onboard something like the works well. Only requires around 10-15 PSI.

Hey Steve,

Found the above on another thread... how does the air over hydraulic setup work? What size is the master that is coupled with that boosted slave? I've been aware of the existence of these, but till now I really didn't know what to call them in search engines.

Thanks,
Cj

PS. I have about 18k on the RR now. Now that I'm reasonably good at shifting the transmission is enjoyable to drive in traffic. Only wish is that I should have spent the extra change for a self adjusting clutch.

 

[Blackduck596]

Cj,
The master is a standard F350 unit. Have a pressure regulator dropping the air pressure to 10-15 Psi. I do have a restrictor in the clutch fluid line as it releases very quick. That came out of a Hyundai clutch master. Not really needed, just have to get use to easing of the pedal. Believe there maybe a couple of different size diaphragms available.
Cheers Steve

 

[cjfisher]

Interesting.... So do you have a picture of the finished setup (clevis etal)? What is the throwout arm length? Do you also have numbers for the slave cylinder bore diameter and travel?

 

[Blackduck596]

Not at home so no gear to measure bore but think it was about 1/18 and stoke around 1 1/14 at a guess.
Center of cross shaft to the clevis is 4" This is a push clutch. Plenty on Fleabay, reasonable pricing and truck dealers up to expensive. While looking may have found a vacuum unit the same, waiting for the vendor to confirm.
Cheers Steve

 

[cjfisher]

Steve,

Did you ever determine what the hydraulic cylinder bore size was? Right now I'm almost one to one on the master/slave bore diameters. Master is 0.875 inches and the slave is 0.827 inches. I'm using an arm to multiply the slave movement. Pushing the master moves the slave 1.36 inches and I need at least 2.4 inches to grab the clutch brake. I see that clutch boosters are all over fleabay.. Unfortunately, I don't see bore specs for any of them.

Cj

 

[Blackduck596]

Sorry, have not been under the truck to measure. Today is out but will try tomorrow. Suspect this will not be enough travel at that length but with the power these have you can shorten the position on the shaft lever.
Cheers Steve.

 

[Blackduck596]

Very rough but looks like 1" bore and 1" travel.
I do not have a trans brake and with"the 4" lever only require around 1/2-3/4" travel to work my clutch. Did not check my master bore but suspect it is 3/4 or 7/8. A standard type Ford master. It will work the clutch without air, just a bit too heavy.
Forget what I did when setting this up, but think I worked the clutch lever and figured out the travel required to work the clutch and that the slave had enough travel to operate without modifying the lever. It only uses a part of the available travel. If I needed more I may have needed a bigger bore master.
Cheers Steve

 

[cjfisher]

Thanks for looking Steve. I did something similar in my setup. I'll have to ponder this. I could change the fulcrum on my setup to accommodate a larger diameter, but it really would up the forces on the fulcrum arm. It would be nice to find a smaller diameter slave (current slave is 0.826 inches ~ 20mm diameter) that would push the full 2.25 inches and eliminate the need for a fulcrum arm in the first place.
How are you stopping the input shaft? Counter shaft brake? Or are you waiting it out/grinding it into gear? The standard F350 master cylinder bore is 7/8 inches in diameter and the original slave is 1.25 inches bore diameter.

Cj

 

[Blackduck596]

Something like a Toyota Ladcruiser has a fairly long stroke. May still have one in the shed, if so will check it;s dimensions.
I have the countershaft brake but never use it. I have an SAE 3 flywheel and think the smaller rotational mass slows down fairly quick. I can throw it through the gears quick, only go slow if skipping gears.
Steve.
1885 Toyota Landcruiser clutch slave, 13/16 bore and 1.6" stroke. Turning a bit off the piston would get a little more stroke. These used a boosted master cylinder.