Transmission options

[Bandit02]

Sooooo....my CAT 3406B arrives Sunday for my swap in the ol M931 - (another thread).

It has a standard SAE #1 flywheel bolted on to run any regular 15" clutch.

I can't use the MT654 as its not rated for input hp this engine will produce. What are my options? Will a 9,10,13,15,18 Eaton Fuller fit underneath?

How about autos? Can anyone recommend one that'll work?

A 3406B paired to a CAT 7155 16 spd would be kinda neat LOL.

 

[quickfarms]

The next week link you need to worry about is the transfer case. Depending on the HP and torque of the new engine it may be like driving the current truck in reverse in low range. You may be ok if you never use low range and baby it.

 

[73m819]

The next week link you need to worry about is the transfer case. Depending on the HP and torque of the new engine it may be like driving the current truck in reverse in low range. You may be ok if you never use low range and baby it.

You can drive in low/r. the reason that the military say NO, is that young GI only knows how to drive with the foot to the floor, he "thinks" that a little power moves the truck so MORE power will move it faster, so as soon as the the truck gets traction, with a lot of power, something breaks, in this case, the transfer. SO it is eaiser and cheaper to say "NO REVERSE IN LOW" and buy 1,000,000 stickers then it is to train young GI how to drive a heavy truck.

ONE way to help in the preventing the transfer issue is DEACTIVATE the AUTO ENGAGE front drive WHEN the truck if put into low range. this is EASY, on the transfer shifting linkage right before the transfer, there is a round washer that hits a spring loaded air switch, just loosen the contact arm and move it out, so the washer can not hit it and activate the front drive.

 

[74M35A2]

Stuff a Road Ranger under there, and then we'll know it is possible and can follow suit. I don't think anybody here has done it yet. Real vehicles have 3 pedals, so I say do it and report back.

 

[red]

A Eaton/Fuller was stuffed into a m819 by a member here. Had to rotate the transfer case so the front driveshaft would clear.

 

[Bandit02]

Perhaps a 10 spd road ranger would be ideal.

I don't think they're as long at the MT654, just wider. My truck is the same frame width as any class 8 truck out there, 34". Cutting a hole in the floor for a shifter isn't my big concern. The clutch linkage & pedal is...

I think I have 1 option = run the hydraulic setup like what Freightliner does on the Cascadia, it will have to use a solo clutch and all I need to do is mount a hinge type pedal/reservoir.

 

[wcuhillbilly]

opcorn: Im patiently awaiting the the outcome. I need a good answer to this for my 816.......

 

[wcuhillbilly]

Seems I remember Trango (or maybe Vintage Iron)... stuffing a 9 or 13 spd if I recall into either an 800 or 900 series truck some time back...
I have heard that the T case has to be moved back some and the front drive shaft tends to hurt the process of a twin counterbalance trans. (eaton/Fuller OTR trans). If you have a front winch PTO driven, this will also dampen the luster, as it has to go or convert to Hyrdo. Im trying to research the Hydro conversion myself,,, my catch keys gave up and dropped a customers ranch truck down a canyon twice on the front winch..... (pulling fine then just freespool to the bottom

 

[73m819]

Seems I remember Trango (or maybe Vintage Iron)... stuffing a 9 or 13 spd if I recall into either an 800 or 900 series truck some time back...
I have heard that the T case has to be moved back some and the front drive shaft tends to hurt the process of a twin counterbalance trans. (eaton/Fuller OTR trans). If you have a front winch PTO driven, this will also dampen the luster, as it has to go or convert to Hyrdo. Im trying to research the Hydro conversion myself,,, my catch keys gave up and dropped a customers ranch truck down a canyon twice on the front winch..... (pulling fine then just freespool to the bottom

The hydraulic DRIVE for the front winch on a 809/39 series truck WILL NOT clear the radiator, the 939 radiator is notched for the drive, one way to get around the radiator issue, is to run the mechanical drive but instead of a pto, mount the hydraulic motor to the frame, then drive the winch drive though a JAW coupling. Another issue will be the mounting of the pto that drives the pump that powers the motor, the fullers are a WIDE transmission, the pto mounts on the BOTTOM, over the road this is not a issue, OFF road it could become a issue real quick, I have seen 10 wheel dumps that get bogged down rip the pto and attached parts OFF in the process of getting it UNBOGGED..

As a side note, pull the front winch and pull it apart, there is almost no way that the drum will freewheel unless the clutch IS DISENGAGED, and that WILL NOT happen UNDER LOAD. IF only barely engaged, the clutch could fall out of engagement, rounding the corners of both parts of the clutch, again you need to pull the left side of the winch and take look at the clutch BEFORE the winch is used again. THERE IS A REASON WHY

 

[wcuhillbilly]

The hydraulic DRIVE for the front winch on a 809/39 series truck WILL NOT clear the radiator, the 939 radiator is notched for the drive, one way to get around the radiator issue, is to run the mechanical drive but instead of a pto, mount the hydraulic motor to the frame, then drive the winch drive though a JAW coupling. Another issue will be the mounting of the pto that drives the pump that powers the motor, the fullers are a WIDE transmission, the pto mounts on the BOTTOM, over the road this is not a issue, OFF road it could become a issue real quick, I have seen 10 wheel dumps that get bogged down rip the pto and attached parts OFF in the process of getting it UNBOGGED..

As a side note, pull the front winch and pull it apart, there is almost no way that the drum will freewheel unless the clutch IS DISENGAGED, and that WILL NOT happen UNDER LOAD. IF only barely engaged, the clutch could fall out of engagement, rounding the corners of both parts of the clutch, again you need to pull the left side of the winch and take look at the clutch BEFORE the winch is used again. THERE IS A REASON WHY

yup.... the front winch has been out of service since this extremely embarrasing debacle happened. frankly the front winch wouldnt engage to wind up the rest of the cable after the last drop. wound up about half of it, then just looped in around the front bumper. need to pull it and rebuild the peicy parts but time and money are never in the same location.

 

[73m819]

yup.... the front winch has been out of service since this extremely embarrasing debacle happened. frankly the front winch wouldnt engage to wind up the rest of the cable after the last drop. wound up about half of it, then just looped in around the front bumper. need to pull it and rebuild the peicy parts but time and money are never in the same location.

They are not that pricy, the clutch is a big jaw clutch, you could build up the jaws, then machine them down, BUT you need to find out WHY not full engagement. I have seen the shifting yolk bent from someone trying to force the clutch to engage when the jaws are not lined up.

 

[Bandit02]

Well I have no winch so one less thing to worry about.

 

[73m819]

Well I have no winch so one less thing to worry about.

As far as the front drive shaft goes, you can always put in as many U-joints as needed to get around what ever trans you are using, the designers of the 939 series had to use 1 U-joint to get around the Allison.

 

[74M35A2]

Seems I remember Trango (or maybe Vintage Iron)... stuffing a 9 or 13 spd if I recall into either an 800 or 900 series truck some time back...
I have heard that the T case has to be moved back some and the front drive shaft tends to hurt the process of a twin counterbalance trans. (eaton/Fuller OTR trans). If you have a front winch PTO driven, this will also dampen the luster, as it has to go or convert to Hyrdo. Im trying to research the Hydro conversion myself,,, my catch keys gave up and dropped a customers ranch truck down a canyon twice on the front winch..... (pulling fine then just freespool to the bottom

I seem to remember earlier somebody saying the twin countershaft transmissions as not fitting well too. Could easily compare the dimensions of both. If this is an issue, does anybody know what the highest number of speeds one can obtain in a non-twin countershaft type trans?

Will also need to look into the hydro clutch configuration. Slave cylinder should simply bolt to the clutch housing or use an internal one which presses throw out bearing forward?

I'm also watching this closely, as I'd readily sign up for the work and $ required to convert my 925A2 over. Hate the slush box, even though it works well and shifts butter smooth, up and down.

 

[red]

All these trucks, deuce, m54, m809, m939, run the standard width frame rails that the civilian side uses. The dual countershaft transmissions fit. Here's a pic from a NTC 400 engine and a Eaton/Fuller dual countershaft transmission install in a M819. From this thread http://www.steelsoldiers.com/showthread.php?18915-M819-RECEIVES-NTC400!!/page8

 

[74M35A2]

Interesting, but that thread died. Nobody knows if a dual countershaft trans can fit into a 939 series and cooperate with the transfer case and front driveshaft. Ugh...

 

[red]

Could always rotate the transfer case a few degrees to gain clearance

 

[Bandit02]

My 3406B has arrived.

It's delivered and paired to a Eaton 10 spd. There's no aux box and its overal length is shorter then the Allison. I believe it'll fit nicely but it doesn't have the correct bellhousing to run a hydro setup that I've seen on western star/freight liner trucks when I was at the dealership. I will think of something ...

 

[Bandit02]

I seem to remember earlier somebody saying the twin countershaft transmissions as not fitting well too. Could easily compare the dimensions of both. If this is an issue, does anybody know what the highest number of speeds one can obtain in a non-twin countershaft type trans?

Will also need to look into the hydro clutch configuration. Slave cylinder should simply bolt to the clutch housing or use an internal one which presses throw out bearing forward?

I'm also watching this closely, as I'd readily sign up for the work and $ required to convert my 925A2 over. Hate the slush box, even though it works well and shifts butter smooth, up and down.

I think 6 is all you get. I've seen 5 ton delivery trucks from international/Freightliner/Sterling and have up to 6 speeds in them before going bigger to a twin countershaft.

The hyrdo setup I want to run uses a special bellhousing and it's run with a Eaton Solo Advantage clutch. The slave piston mounts to the bellhousing and the reservoir mounts to the firewall like any regular pickup would.

Sadly, since my 10 spd showed up free with my engine I have to run with this now. I will run the Eaton easy-pedal clutch with it and I have no issues doing the occasional clutch adjustment when it needs it, I have replaced far too many solo's under warranty. The self-adjustment mechanism seizes up when guys don't clutch regularly, plus is about 40 lbs lighter then the solo too

 

[red]

Which model 10 speed?