Build Splurge Overkill - FJ60 build

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isbj60 said:
Thanks!

The transmission is an Eaton Fuller. It is part of Eaton's truck drivetrain component line they call Roadranger. That includes axles, clutches, etc. These transmissions come in a wide range of styles. Hundreds. Mine is a RTO-14709mll. To break that down: rto stands for Roadranger Twin countershaft Overdrive. The 14 is the nominal torque input rating, in hundreds of foot-pounds (actually 1450 for this model). The 7 is the design level (6 had straight cut auxiliary gears [loud!], 7 had helical cut ones, and 9 has an improved rear output seal design.) The last two digits are the number of forward road gears. 9 in my case. The next letter is the ratio identifier (in my case, the M is a lower deep reduction reverse gear than the A gearset that was also available). The last two letters indicate that there are two deep reduction gears below the 9 road ratios, meaning this transmission is actually an 11 speed. The two deep reduction gears are not meant for progressive shifting, only for speed control. Whew!
This particular transmission was used extensively in cement mixers and dump trucks, so they could go slow enough to keep pace with paving machines and not burn clutches. Usually those trucks have GVW's around 60,000 pounds. Often they had the Cummins ISC (8.3L) or ISL (8.9L) as a powerplant, too... It is not a very common model, so I looked for a while to find one that I could get for a good deal. They are spendy otherwise.
The RTO line of transmissions are known for being extremely tough, long lasting, and easy to shift (even though there are no synchronizers in the front half of the transmission). It's not unheard of for these to go 500,000-750,000 miles between overhauls, and millions before they are scrapped. And those are hard miles. Mine has 130,000 on it and internally looks new from what I can see.
I will post a link to all of Eaton's literature on the beast as soon as I get to a computer since the app on my phone is not cooperating. The service manual is an excellent read, I think. Lots of pictures, and has all the power flow diagrams for each gear ratio to help visualize how it works.
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Thanks. You're not building a dump truck, but you can tow one. Lol Are you gong to have a split axle on this thing?
 
I looked into those and there are two big negatives that are keeping me from going that route. I could not find a model that had a high range faster than 4.11. Dosn't mean they don't exist, but I want something more common so it will be less expensive. Also, the two speed actuator goes where the locking differential actuator goes, so it's either or. I want the locker...
 
isbj60 said:
I looked into those and there are two big negatives that are keeping me from going that route. I could not find a model that had a high range faster than 4.11. Dosn't mean they don't exist, but I want something more common so it will be less expensive. Also, the two speed actuator goes where the locking differential actuator goes, so it's either or. I want the locker...
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Yeah the locker would be a little more usable that the two speed I would think. With all the weight you are gonna have it will come in handy. If you've ever driven a 10 wheeler off road at all then you already know.....
 
BTW, how about some pictures of the components you are putting in (Axles, transfer case, engine) now, so we have an idea of just how over the top this thing is. I mean, throwing numbers and the names of components we have never heard of is okay if you have the time to research things, but a picture is worth a thousand words.
 
man this thread is way over my head but it's gonna be awesome when finished.

MORE PICS
 
Wyoming said:
BTW, how about some pictures of the components you are putting in (Axles, transfer case, engine) now, so we have an idea of just how over the top this thing is. I mean, throwing numbers and the names of components we have never heard of is okay if you have the time to research things, but a picture is worth a thousand words.
Click to expand...

Griffin said:
man this thread is way over my head but it's gonna be awesome when finished.

MORE PICS
Click to expand...

More pics, indeed! When the funding floodgate opens in December, I will be buying a lot of the stuff necessary. Like the rear axle, engine, brakes, steering. Little stuff. Right now I just have some pieces I've been collecting for a few years. Lame, I know. I just bought a (eventually) kick-arse air compressor, but that is soaking my time and funds right now. Maybe a build thread on that is in order in the meantime...:D
 
I have posted my side project in the tools section.

I plan on spending some time this weekend drinking heavily, then irreversibly hacking up the transmission tunnel for the transmission. Got to be done in that order...:p
 
Started the tunnel modifications. Did not take as much whiskey as I had thought. After the first check fit, here are the cuts.

tunnel mod 066.webp
tunnel mod 067.webp
tunnel mod 068.webp
tunnel mod 066.webp
tunnel mod 067.webp
tunnel mod 068.webp
 
Shots from underneath.

tunnel mod 072.webp
tunnel mod 073.webp

Placing the transmission in the tunnel and matching the slope creates quite the engine angle. What do you guys think?

tunnel mod 074.webp

I really don't want to raise the back, since that will push the t-case up into the passenger's feet. Might have to, though, otherwise the front of the engine will stick out of the hood by 6" or so! To those with stock setups, what slope do you have on your motor?

Off to do more cutting. Round two of pics will follow.
tunnel mod 072.webp
tunnel mod 073.webp


tunnel mod 074.webp
 
how many degrees? I'd not go much more that 5 or so. I do know of people that run >13 but it's not for me. And this is not a rock rig, it's a pavement pounder. No reason to blow it's intended purpose.
 
4-5 degrees is fine for a cummins, I believe as per the FSM it states you can run up to 8 degrees of angle front to back and 13 degrees side to side.

Transmission looks good, I wouldn't raise it too much though you might run out of room above the engine in the engine bay.
You might want to set the final height once you have the drivetrain bolted together.
But it does look good up in the tunnel there.
 
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