allison swap?
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Cross-Country
Joined: Apr 2017
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From: Salt Lake City
allison swap?
does anyone have info about swaping in a 6-sp Allison transmission onto a 6.9L F350 C/C? I'm planning to swap out the 3-sp C6 I have so I can actually achieve freeway speeds, and the allison looks like my best choice. I'm not worried about body mods to make it fit, but I am a little worried about running an electronic transmission on a mechanical engine, and mating it to an engine. I also haven't been able to figure out how to set up a gear selector for it, since I also want to move the selector off my column and onto the floor, like the Lokar cable-operated shifter.
Any help would be really appreciated and will help me get this part of the project past the planning stages.
Any help would be really appreciated and will help me get this part of the project past the planning stages.
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Joined: Jan 2001
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From: Virginia
Never heard of a Allison behind a old idi diesel. Most people get a updated and rebuilt E4OD and put it behind it, or do like I did and put a zf 5 speed behind it.
If you looked hard enough, you could probably come up with a idi to SAE bellhousing adapter and may be able to bolt up a heavy truck trans to it. I don't know, most people don't go that way.
If you looked hard enough, you could probably come up with a idi to SAE bellhousing adapter and may be able to bolt up a heavy truck trans to it. I don't know, most people don't go that way.
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Cross-Country
Joined: Apr 2017
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From: Salt Lake City
What I'm trying to do is get the truck to be a bit more fuel efficient, be able to hit 80+ mph, and not have to use a manual. I got tired of running manuals as a trucker.
I can source a bus-grade Allison and possibly even the control panel from my work at a city bus agency. I might be able to have Allison re-gear and re-program it for light-headed duty, rather than bus. But all that seems expensive vs a 6sp Allison from a Chevy light truck.
Are there any other transmissions that are as reliable as Allison's, and will get me at least 5sp in auto?
I can source a bus-grade Allison and possibly even the control panel from my work at a city bus agency. I might be able to have Allison re-gear and re-program it for light-headed duty, rather than bus. But all that seems expensive vs a 6sp Allison from a Chevy light truck.
Are there any other transmissions that are as reliable as Allison's, and will get me at least 5sp in auto?
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Joined: Jan 2001
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From: Virginia
The transmission selection for the old diesels is poor. If you want overdrive, the E4OD or the zf are the best and easiest options. You can also find add-on overdrive units, but if you put them behind a c6 you still have the torque convertor slippage, the c6 does not have a lock-up convertor. Does the Allision have a lock-up convertor? They are worth a drop of at least 200 rpm on top of the OD gear.
I will tell you your international diesel engine has a oddball international bellhousing pattern. Ford made a adapter to another oddball diesel only pattern(way to go Ford) that bolted to the back of the engine to use their oddball diesel pattern transmissions.
School buses and U-haul moving vans also used the international engine, as well as some dump trucks. These engine used an adapter to go from the oddball international pattern to a standard SAE pattern. If you want to play around with heavy truck and bus transmissions, you are going to have to find one of these SAE adapters.
I will tell you your international diesel engine has a oddball international bellhousing pattern. Ford made a adapter to another oddball diesel only pattern(way to go Ford) that bolted to the back of the engine to use their oddball diesel pattern transmissions.
School buses and U-haul moving vans also used the international engine, as well as some dump trucks. These engine used an adapter to go from the oddball international pattern to a standard SAE pattern. If you want to play around with heavy truck and bus transmissions, you are going to have to find one of these SAE adapters.
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Cross-Country
Joined: Apr 2017
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From: Salt Lake City
Sounds like I'm gonna have a tough time with getting the truck up to where I want it.
so if I can source the bell housing adaptor, that will deal with mating the trans to the engine?
so if I can source the bell housing adaptor, that will deal with mating the trans to the engine?
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Joined: Jan 2001
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From: Virginia
If you get the right SAE trans, it should bolt up. But you mentioned before about the trans fitting the truck and you are correct, those big truck transmissions are very large and heavy, and will probably hit the floorboard among other things.
You can start to get in the world of diminshing returns with these trucks sometimes. Some people put medium duty truck drivelines in these pickup based trucks, but they never think about the brakes, never think about the original GVWR of the truck itself, and don't think about DOT legalities when hauling very heavy loads. It can get out of hand quick.
Just remember, you are using a pickup based truck, even though it's a heavy duty model with a dually rearend. It is what it is sometimes.
You can start to get in the world of diminshing returns with these trucks sometimes. Some people put medium duty truck drivelines in these pickup based trucks, but they never think about the brakes, never think about the original GVWR of the truck itself, and don't think about DOT legalities when hauling very heavy loads. It can get out of hand quick.
Just remember, you are using a pickup based truck, even though it's a heavy duty model with a dually rearend. It is what it is sometimes.
Cargo Master
Joined: Oct 2005
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From: NJ
What's wrong with a ZF5 or E4OD? Bolt up and you can cruise at 2000 RPM at 70 MPH with 3.55:1 gears. I doubt my IDI with 100cc pump and Banks turbo has the low end grunt for a double overdrive. Maybe empty and on level ground, maybe... But I'd wager it would lug and smoke and EGT would skyrocket. You'd need a turbo that builds appreciable boost at low RPM.
If you need more gears for heavy loads you can run a NP435 or T18/19 with a Ranger overdrive unit ahead of it. I'd sooner do a 2 or 3 speed aux trans before I'd go down the huge power robbing big truck trans route. These engines don't make much power to begin with, an automatic doesn't help matters and I bet those big automatics take a lot of power just to operate.
If you need more gears for heavy loads you can run a NP435 or T18/19 with a Ranger overdrive unit ahead of it. I'd sooner do a 2 or 3 speed aux trans before I'd go down the huge power robbing big truck trans route. These engines don't make much power to begin with, an automatic doesn't help matters and I bet those big automatics take a lot of power just to operate.
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From: Roseville, MN
What's wrong with a ZF5 or E4OD? Bolt up and you can cruise at 2000 RPM at 70 MPH with 3.55:1 gears. I doubt my IDI with 100cc pump and Banks turbo has the low end grunt for a double overdrive. Maybe empty and on level ground, maybe... But I'd wager it would lug and smoke and EGT would skyrocket. You'd need a turbo that builds appreciable boost at low RPM.
If you need more gears for heavy loads you can run a NP435 or T18/19 with a Ranger overdrive unit ahead of it. I'd sooner do a 2 or 3 speed aux trans before I'd go down the huge power robbing big truck trans route. These engines don't make much power to begin with, an automatic doesn't help matters and I bet those big automatics take a lot of power just to operate.
If you need more gears for heavy loads you can run a NP435 or T18/19 with a Ranger overdrive unit ahead of it. I'd sooner do a 2 or 3 speed aux trans before I'd go down the huge power robbing big truck trans route. These engines don't make much power to begin with, an automatic doesn't help matters and I bet those big automatics take a lot of power just to operate.
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Cross-Country
Joined: Apr 2017
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From: Salt Lake City
What's wrong with a ZF5 or E4OD? Bolt up and you can cruise at 2000 RPM at 70 MPH with 3.55:1 gears. I doubt my IDI with 100cc pump and Banks turbo has the low end grunt for a double overdrive. Maybe empty and on level ground, maybe... But I'd wager it would lug and smoke and EGT would skyrocket. You'd need a turbo that builds appreciable boost at low RPM.
If you need more gears for heavy loads you can run a NP435 or T18/19 with a Ranger overdrive unit ahead of it. I'd sooner do a 2 or 3 speed aux trans before I'd go down the huge power robbing big truck trans route. These engines don't make much power to begin with, an automatic doesn't help matters and I bet those big automatics take a lot of power just to operate.
If you need more gears for heavy loads you can run a NP435 or T18/19 with a Ranger overdrive unit ahead of it. I'd sooner do a 2 or 3 speed aux trans before I'd go down the huge power robbing big truck trans route. These engines don't make much power to begin with, an automatic doesn't help matters and I bet those big automatics take a lot of power just to operate.
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From: Virginia
I was thinking about your situation later on, and realized why putting that trans to that engine is so uncommon. Most people I read about put the tranny AND the medium duty engine in place also, getting rid of the old idi international. It's a good reliable engine, but it is limited in it's power potential. There are inline medium duty engines that have lots of potential power and can be turned way up that need a large trans like that. But like I said, putting all this in a pickup based truck makes it more of a play toy more than anything.
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