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Discussion Starter #1
I have a 96 bronco I'm putting a 4bt into. This 4bt has a p7100 and is mated to an E4OD transmission. I have a TPS sensor from a 12 valve and its accompanying bracket to hold the sensor. I was going to use it so my transmission can shift into overdrive and whatnot, but my linkage is wrong. What came with the engine was for a manual transmission I believe. I searched high and low, called more than a dozen shops, looked at craigslist, facebook marketplace, and local junkyards in a 50 mile radius and can't find the Cummins throttle linkage part#4089112. It's discontinued and no one has it.. I'm kind of at a loss of what to do for the linkage now.

So, I imagine someone here must have run into this same issue once already. Can someone help me come up with a solution for this issue? Fabrication shouldn't be an issue as I have one local to me. Just not entirely sure the best way to go around this as this is my first foray into diesel, this engine, and such a large job as this.
 

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The guys at CPP show it but it's currently on backorder. Here's the setup on ebay. Hope you're sitting down because it's $684.07. Cummins 12 Valve Throttle Kit 4089112 | eBay Here's another at Transport Diesel for $422.81. Genuine Cummins 4089112 KIT,THROTTLE - Transport Diesel Diesel Parts direct has it for $568.19. PC Industries has it for $473.11. No matter how you look it's not a cheap part kit but it is available. Might contact member CrewCab59. He's a Cummins dealer and may have a better price.
 

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Discussion Starter #3
Thanks for the heads up! I did reach out to all of those places, including the ebay listing to ask if they'd take a lesser offer, and no one has it and the ebay location said no. However, the ebay shop is one of the shops I called and they said they didn't have it, so I don't know what that's about. I also contacted a local Cummins dealer and a Dodge dealership to see if I could get one, but it appears pretty much no one in the country has that complete set. The hardest parts to source are the brackets themselves. I'm wondering if there isn't a custom setup someone has already done in an application like this that can shed some insight, I don't even know if this part will work haha. It seems like one or two mount points for those brackets don't exist on my current P7100
 

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That kit is just the throttle linkage and bracket. I had read there is another part to the puzzle for automatics which is the bracket for the TPS. That is part 3925380. Probably the reason you don't find tons of those kits is that they would seldom be replaced. Don't know where you're located but I might try calling Cummins Atlantic tomorrow and see if they show any in the computer network.
 

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Discussion Starter #5 (Edited)
I'm located in MD - I have bracket PN 3931556 and the TPS to go with it already, Just need the linkage (I think). The Cummins shop I called here said it is backordered with no supplier, so probably won't be made again, and the Dodge dealership said both of those brackets were discontinued in 2017, unfortunately. But I welcome the help, maybe I just have terrible luck. Here is the bracket and sensor I have currently that I got from DieselConversionSpecialists:


I'm not entirely certain that linkage will work on the 4bt, but it should work for my sensor and bracket. The brackets #11 and #15 seem to be nonexistant in the picture below. I found a single #11, but #15 I can't find anywhere. But in the interest of not dropping $700 bucks on the assembly, though, I'm hoping someone else has solved this conundrum and can help me with some fabrication ideas on a cheaper solution haha
 

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Why don't you simply skip using a special bracket & just mount your TPS where ever the harness allows you....no need to have it controlled by the throttle at all. Install a Potentiometer with dial in your dash so you can control exactly when your transmission shifts. See diagram
127144
 

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Discussion Starter #7
I'm not entirely certain mechanically what this does, I'll research potentiometers. I also know next to nothing about electrical work and automatic transmission operation so I'll try to brush up quickly. With an automatic transmission, would it not be better to have the TPS decide when to shift? Is the potentiometer making it so I'd have to manually tell the transmission to shift every time I need it to shift?
 

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TPS is only controlling when the overdrive kicks in. The PCM is looking for a voltage ( if memory serves me right...about 1.0 V ) & XX amount of vehicle speed. The potentiometer simple allows to to fine tune exactly when you like the OD to come in. The PCM will automatically kick the OD out when the speed drops below what ever threshold is built into the PCM.
Another option ( I have used this one on my old 93 Dodge Cummins when the inj pump was maxed out & the throttle bracket was moded for more throttle travel...the TPS would turn to far, which gave me OD too quick in the rpm for my liking ) ...you can also simply bend a piece of copper wire in kind of a Z shape to keep the TPS turned to a permeant voltage of your liking and no need for the potentiometer. Harder to get it tuned this way but once you find your sweet spot, your done & again the TPS can just be zip tied safely anywhere you like.
hope this helps you.
 

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Discussion Starter #9 (Edited)
Oh interesting. Exactly when to shift based on speed alone it seems like? It doesn't seem like it's a toggle switch, but more like a variable switch? I only did superficial reading as last night was a late work night. Some good basic literature for other new folks like me about potentiometer installs: Replacing the TPS with a potentiometer -A - Dodge Cummins Diesel Forum

Something I'm trying really hard to keep, though, is my cruise control and I read in a place this would effectively neutralize it. Do you have any insight on that?
 

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Impact, I did contact Cummins Atlantic in Charlotte NC and they didn't have any leads to the throttle kit either. If was worth a shot but struck out. That guy on ebay may be the only one in the country.
 

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As mentioned keep the TPS plugged in & I know if the TPS is "wired" into a fixed position like what I did, cruise control still works.
 
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