Twin tranny puller

Tue Aug 13, 2013 4:54 pm

Hey guys

I have been trying to get a little extra pulling power out of my cub cadet 100 pulling tractor, recently putting in a 12hp Kohler (replacing the factory 10hp) and also adding a creeper drive unit. The more i read about the creeper drive though, it seems like its pretty weak in comparison with the rest of the drive train. I was wondering what everyones thoughts would be on taking out the creeper drive, lengthening the frame, and installing a farmall cub transmission (or cub cadet with the PTO shaft) in front of the the regular transmission, there by reducing input speed and increasing torque. Any ideas on pros/cons????? thanks

P.S- i also have installed a East Coast Pulling Parts HD pulling clutch/driveshaft.

Re: Twin tranny puller

Tue Aug 13, 2013 5:03 pm


I can't speak to your question, however, Midwest Super Cub is a source of products/information for all things on pulling Cadets.

Looks like you are having fun! Good luck!


Re: Twin tranny puller

Wed Aug 14, 2013 6:56 am

If you're talking about pulling weight sleds, then I think you better talk to some guys that do tractor pulling. From what I know about it, I don't think you want to do either of the things you mention above. Typically, tractor pulling setups run second gear, which gives you the right amount of ground speed, pulling power, and throttle control, so you can adjust the wheel speed as needed by throttle while pulling. If you use a creeper drive or try to use a secondary tranny as an underdrive (which I don't think is nearly as easy as you are describing), your ground speed is going to be way too slow, and you'll loose the help that you get from momentum of the sled.

If you're talking about being able to pull stuff around the house, boats, logs, trailers, etc., then a creeper drive is exactly what you need. Slow speed, lots of power. They're pretty bullet proof for what they were intended, giving the tractor slower gears so that the throttle can be left wide open to run attachments like a snow blower or roto tiller, thus slowing the ground speed of the tractor yet keeping the throttle wide open so the PTO driven attachments are running at the correct speed for their intended use.

Oh, by the way, a farmall cub transmission does not have the primary underdrive gear that is in the front of a Cub Cadet tranny. The underdrive gear changes the rotation of the engine in a Cub Cadet tranny and also changes the input RPMs. The final drives in a Farmall Cub take care of this. So, if you just try to slap in a Farmall Cub tranny, you will have 3 gears in reverse, one forward. So, like I said above, not nearly as easy as you were thinking.

Re: Twin tranny puller

Wed Aug 14, 2013 7:43 am

gitractorman wrote:If you use a creeper drive or try to use a secondary tranny as an underdrive, your ground speed is going to be way too slow, and you'll loose the help that you get from momentum of the sled.
Echos my thoughts. You can do some math to figure out your ground speed, if you know the gear reduction of the creeper or the secondary transmission.

My Cub 154 Low-Boy with creeper. Ground speed with tractor in 3rd gear and creeper engaged is slower than 1st gear without the creeper.

Re: Twin tranny puller

Wed Aug 14, 2013 10:09 am

Another thought about the twin trans idea. Rock crawling trucks use low speed, with high power to the ground, high reving engines, large tires and wheels, and serious gear reduction is necessary. Often these trucks will use twin transfer cases (called doublers) which gives them basically a double low range when both cases are in low range. That amounts to about 4X the gear reduction of high range. These trucks are pretty heavy too with lockers front and rear with some pretty deep gears (4.56, 4.88, 5.13...). Bottom line - it's about 1) getting power to the ground, and 2) TRACTION. If you can't hook up all the power in the world won't help, this is true in any wheeled power sport. What you need is a blend of power, speed, and traction for whatever you're trying to build/pull. If you're pulling a sled I think I'd concentrate on power and traction. Like the others I wouldn't worry about any more gear reduction, your Cubs trans and the driveline you have are up to the job.

Re: Twin tranny puller

Wed Aug 14, 2013 4:44 pm

Thanks for all the input guys. One thing i probably should have specified is that im doing stone boat pulling, not transfer sled. This past weekend i participated in a local tractor pull. my max pull was 5000lbs for 10in. (full pull is 36in for our club). i never lost traction, clutch never slipped, and front end was floating pretty well (therefore transferring all weight to the rear wheels). I just ran out of power. I was using 1st gear in "high range" of the creeper (word has it the planetary gears of the "low range" gear set aren't very strong). And while the Farmall cub transmission is lacking the speed reducer/rotation reverser, cant i just unbolt the ring gear/carrier assembly and flip it 180* to correct the rotation? please correct me if i have any info wrong, and keep the advice coming, thanks

Re: Twin tranny puller

Wed Aug 14, 2013 7:13 pm

First thing I would do is remove the creeper gear. They were not design for pushing-pulling a load. The gears are the weak link.

Best thing you can do is up the horse power in the engine in one of two ways: modifing the current engine or a bigger engine.

It sounds like you have the balance set. I wouldn't mess with it.

Re: Twin tranny puller

Mon Aug 26, 2013 10:29 pm

The weakest link is the pins in the drive shaft. I put in some standard heavy duty ones from McMaster Carr a few years back the there holding up.

Re: Twin tranny puller

Sat Dec 14, 2013 9:12 pm

If you're planning to hook the PTO of the Farmall Cub transmission to the input of the Cadet transmission the only problem I see is that the Cub PTO is the same speed as the input and only changes with engine speed. It doesn't go through the transmission gear changes. You'd have to connect to the Cub transmission axle output to get benefit of gear changes. Using the axle output would have it's problems. The axle is 90 degrees to the input of the Cadet transmission so your driveline would have to "go around a corner". If you use one axle you'd have to lock the other side or the differential would spin and you wouldn't go anywhere. If you lock one side you're going to double your output speed on the other side which may negate any benefit from the whole setup.

Sorry, I don't have an answer for what you want to do other than to scratch this one and keep trying. Remember we don't have WD1 through 39 because it was on the 40th try that it worked! Keep asking questions though that's the best way to learn. I'll be following along because it sounds like you'll get this figured out and I'm curious how it'll turn out.

Re: Twin tranny puller

Sun Dec 15, 2013 7:05 pm

Having read this again, there might be a single thing to change that will increase your pulling power. On the input side of a cub cadet transmission is a big reduction gear. It takes the engine speed, reverses the direction, and slows the RPMs down, to give you your standard speed intended for the Cub transmission . See, part of the gearing in a Farmall Cub comes from the final drives, which slow down the transmission speed to give the correct ground speeds. So when they went to use the Cub transmission in a Cub Cadet (which doesn't have the final drives like a Cub), they needed a reduction gear to get the speeds correct without making all new gears for the transmission (thereby utilizing the exact same tranny in both tractors).

Anyway, Changing this input reduction gear would significantly change the gearing in the transmission, and your ground speed. Additionally, it is a VERY heafty gear, about an inch thick steel, so there's pleanty of monkeying you could do and not harm anything. The biggest limitation is the gear housing, so this would be the tricky part. If you swap out gears you'll likely get outside of the reduction housing. However, the housing is about 2" thick, and nothing special. You could certainly cut out plate steel, maybe 1/2" plates, stacked like doughnuts, then welded together to make a new reduction housing that would fit your new gears.

A little math would figure out what you need from gears, but I think this is where I would go if I wanted to build a puller like you're talking about. Plus, cosmetically, the tractor wouldn't look at all different, as everything would be hidden in the frame like the tranny is now. No extra levers, etc.

Anyway, just a thought.


Re: Twin tranny puller

Sun Dec 15, 2013 9:58 pm

Aron did some brainstorming with Cecil at the August MiniFest.
At CubFest Northeast, with the help of Scot, he was able to get his "brainstorm" working. Over the Thanksgiving weekend he completed the installation.
I'll let Aron post some photos of his tractor with the latest modifications. He plans on removing the creeper gear to prevent damaging it. He will need a new drive shaft.


Re: Twin tranny puller

Mon Dec 16, 2013 10:40 pm

Thanks for all the input guys. Here is what Cecil and Scott helped me come up with. And like my dad said, i will be removing the creeper soon to prevent damage.
Thanks again for all the help and advice.

Here is a video link to a crawl test that i did. by my rough math its about .03 mph- Creeper in low range, 1st gear, engine at idle

Re: Twin tranny puller

Sat Feb 01, 2014 4:37 pm

That's interesting you have the gear reduction of the finals, the gear reduction on the cadet tranny, plus the low range of the creeper too? Each gear reduction multiplies the torque. Now it's between the out put of the engine and the traction. I'd say build the engine. You need the biggest bore cylinder, with a longer rod with the longest stroke crank. I'm sure with all the different Koehler pistons, rod lengths and cranks the right combination will work for a stroker.

Re: Twin tranny puller

Sat Feb 01, 2014 10:35 pm

Stroker engines cost big $$$$$$. I doubt you can use Kohler parts without some serious mods $$$ done to them.
Boring an engine to the next horsepower size (12 horse power engine to a 14 or 16 horse power piston) is a wreck waiting to happen.
A cheaper and easier way to make some serious power can be made by changing cam and some mods to the valves. Check with some of the sites that sells pulling parts. They can recomend a good set up for your puller.

Re: Twin tranny puller

Sun Feb 02, 2014 9:32 am

Merk Stated: check with some of the sites that sells pulling parts

Years ago I found this man. I haven’t been in contact for a few years…I guess he’s still around….he had good engine building tips….