Dodge NV4500 and NP241 to Chevy Speedo?
4BTSwaps.com is the premier Cummins Forum on the internet. Registered Users do not see the above ads.
+ Reply to Thread
Results 1 to 15 of 15

Thread: Dodge NV4500 and NP241 to Chevy Speedo?

  1. #1
    Registered User
    Join Date
    Mar 2011
    Location
    Simi Valley, CA
    Posts
    27
    Thanks
    0
    Thanked 0 Times in 0 Posts

    Default Dodge NV4500 and NP241 to Chevy Speedo?

    I've used google and the forum search function but cannot find any answers that directly relate, hoping someone here can help.

    Swapping a 95 12 valve/Dodge NV4500 and NP241 into a 1993 Suburban K2500. The problem is getting the Chevy speedo to work. According to what I've seen, theres too many downsides to the basic options.

    Dodge NV4500 to Chevy NP241 wont work because of bolt patterns, and the input shaft will be too weak, Dodge NV4500 and Dodge NP241 wont allow the speed to work unless we put some kind of reluctor ring on the tailshaft, or use the Dodge NV4500, and the Dodge NP241 but use the chevy tailhousing to use the chevy speedo, but then the tailshaft would be weak. Can anyone point me in the right direction? Is it possible to use the dodge tailshaft and the chevy tailhousing, and is there a reluctor ring that can be put on the tailshaft itself inside the housing so its not on the outside of the case? Thanks guys!

  2. Remove Advertisements
    4BTSwaps.com
    Advertisements
     

  3. #2
    Registered User
    Join Date
    Jul 2008
    Location
    East coast
    Posts
    104
    Thanks
    0
    Thanked 1 Time in 1 Post

    Default

    Speedo signals are usually simple square wave outputs, it's the cycles per revolution that is important to the speedo. Might be easier to figure out what the dodge speed sensor output is and what the Chevy computer is expecting and figure out if the two can talk. How do Dodge and Chevy handle the speedo ratios? Most newer cars it's modified in the computer vice older vehicles where you would have to change speedo gears. So even if the pulses/revolution isn't the same between the two vehicles a reprogramer might let you trick the Chevy into using the Dodge signal and still be fairly accurate.

  4. #3
    Registered User
    Join Date
    Mar 2011
    Location
    Simi Valley, CA
    Posts
    27
    Thanks
    0
    Thanked 0 Times in 0 Posts

    Default

    Quote Originally Posted by Desoto61 View Post
    Speedo signals are usually simple square wave outputs, it's the cycles per revolution that is important to the speedo. Might be easier to figure out what the dodge speed sensor output is and what the Chevy computer is expecting and figure out if the two can talk. How do Dodge and Chevy handle the speedo ratios? Most newer cars it's modified in the computer vice older vehicles where you would have to change speedo gears. So even if the pulses/revolution isn't the same between the two vehicles a reprogramer might let you trick the Chevy into using the Dodge signal and still be fairly accurate.
    Upon further investigation, I've come across a few different sites pointing me to Dakota Digital. They have a speed calibrater. I've also seen that to use the Chevy 241 on the back of the Dodge 4500, all we need to do is use the Chevy 4500 Mainshaft and tailhousing, and the Chevy 241 will bolt right up. If this is true, then we could go with a Billet Chevy NV4500 Mainshaft, and the worries about the Chevy shaft being weaker are all gone. If this is the case, then I have a signifigant hope of doing my own 4500 swap when I finally get around to doing my own cummins swap, since my plans for mine are to run the 4L80e with a stand alone controller, giving me time to finance my NV4500 built

    A second question that I forgot to ask:

    What to do for the Tachometer pickup? The truck has a 454 right now, so the pickup is off the crank, right? How do we adapt the Cummins to the Tach? All the info I find says the alternator drives the tach, someone else told me this truck gets its tach signal from the coil plugs, and a few people say its off the crank. Does anyone know if this is true? Whatever the Suburban is using now is the route we're going to take, to save money and save us from the wiring nightmare I'm sure it would become to use a method other than what this truck currently uses. Thanks guys!

  5. #4
    Registered User
    Join Date
    Jul 2008
    Location
    East coast
    Posts
    104
    Thanks
    0
    Thanked 1 Time in 1 Post

    Default

    Quote Originally Posted by 93FatBottom View Post
    Upon further investigation, I've come across a few different sites pointing me to Dakota Digital. They have a speed calibrater. I've also seen that to use the Chevy 241 on the back of the Dodge 4500, all we need to do is use the Chevy 4500 Mainshaft and tailhousing, and the Chevy 241 will bolt right up. If this is true, then we could go with a Billet Chevy NV4500 Mainshaft, and the worries about the Chevy shaft being weaker are all gone. If this is the case, then I have a signifigant hope of doing my own 4500 swap when I finally get around to doing my own cummins swap, since my plans for mine are to run the 4L80e with a stand alone controller, giving me time to finance my NV4500 built
    Well still might be worth looking into the signal issue, it sounds like it would be far cheaper to figure out how to use the Dodge speed sensor with the Chevy speedo than all that.

    A second question that I forgot to ask:

    What to do for the Tachometer pickup? The truck has a 454 right now, so the pickup is off the crank, right? How do we adapt the Cummins to the Tach? All the info I find says the alternator drives the tach, someone else told me this truck gets its tach signal from the coil plugs, and a few people say its off the crank. Does anyone know if this is true? Whatever the Suburban is using now is the route we're going to take, to save money and save us from the wiring nightmare I'm sure it would become to use a method other than what this truck currently uses. Thanks guys!
    I don't know the specifics for your engine but again, the computer will be looking for some sort of pulsed input in some proportion to engine speed. You can generate that signal off of any of the above items, it's just a matter of what number of "pulses" the computer expects to see per engine revolution, then generating the same thing off the Cummins.

  6. #5
    Registered User
    Join Date
    Mar 2011
    Location
    Simi Valley, CA
    Posts
    27
    Thanks
    0
    Thanked 0 Times in 0 Posts

    Default

    Quote Originally Posted by Desoto61 View Post
    Well still might be worth looking into the signal issue, it sounds like it would be far cheaper to figure out how to use the Dodge speed sensor with the Chevy speedo than all that.
    Which part, swapping the mainshafts and tailhousings? Or using a 4L80e trans instead of a dodge trans? The dodge speed sensor can't be used from what I'm reading. Well enough, trying to maintain as much chevy as possible.

    I don't know the specifics for your engine but again, the computer will be looking for some sort of pulsed input in some proportion to engine speed. You can generate that signal off of any of the above items, it's just a matter of what number of "pulses" the computer expects to see per engine revolution, then generating the same thing off the Cummins.
    What I don't get is how so many people manage to use the tach and still throw out the ECM from the truck after the swap is completed, you say we need the ECM to maintain the tach?
    Last edited by 93FatBottom; 11-22-2011 at 06:03 AM.

  7. #6
    Registered User
    Join Date
    Oct 2010
    Location
    Gig Harbor, WA
    Posts
    226
    Thanks
    0
    Thanked 1 Time in 1 Post

    Default

    Quote Originally Posted by 93FatBottom View Post
    What I don't get is how so many people manage to use the tach and still throw out the ECM from the truck after the swap is completed, you say we need the ECM to maintain the tach?
    I had a 454 in mine. I bought a tach signal kit from Autoworld MT, it is a 4-pulse.

    The tach doesn't work through the computer at all. It has its own wire.

    That being said, there is a spot on the computer that is for the tach signal, this is just to let the computer know what the rpms are so it can shift, etc. When I first did my conversion, I didn't run the tach wire to the computer, when I hooked up all the A/C components, I decided to run that wire since I wasn't sure if the computer needed to see engine speed to turn on the A/C.
    1996 Suburban 454 to 6BT Conversion.
    http://www.4btswaps.com/forum/showth...d-up-with-pics

  8. #7
    Registered User
    Join Date
    Apr 2008
    Location
    Kansas
    Posts
    152
    Thanks
    0
    Thanked 0 Times in 0 Posts

    Default

    I talked to dakota digital before and it sounded really expensive especially when you can go to best buy and buy a tomtom or garmin and have a extremely accurate GPS speed reading, directions, and a accurate mileage account for around $200 or less.

  9. #8
    Registered User
    Join Date
    Nov 2008
    Location
    Floyds Knobs, In
    Posts
    244
    Thanks
    0
    Thanked 0 Times in 0 Posts

    Default

    I swapped a 95 5.9 and 241dhd into my 97 suburban. On the speed sensor this is what I did.....Remove the Dodge tail housing and speed sensor ring (the ring looked just like a speedo ring on the tailshaft of an old manual transmission). My Sub had a 241 transfercase also. (whichever one GM uses, but it was a 241) Removed the tailhousing from the GM case, and also removed the tone ring from its' output shaft. Placed the GM tone ring on the Dodge output shaft and then placed the GM tailshaft housing onto the Dodge 241dhd. Used the GM VSS and seems to work just fine. I haven't driven it at highway speeds yet, just up and down the driveway and around a couple open acres, but all seems good so far.
    ..............I don't know if the 93 GM t-case and my 97 GM t-case are the same, but the output shaft of the Dodge 241dhd was the same as my 97 GM....as far as the Dodge speedo gear and the GM tone ring swapping out.
    Last edited by CumminsBronco; 11-21-2011 at 10:35 PM.

  10. #9
    Registered User
    Join Date
    Mar 2011
    Location
    Simi Valley, CA
    Posts
    27
    Thanks
    0
    Thanked 0 Times in 0 Posts

    Default

    Quote Originally Posted by Crummins View Post
    I had a 454 in mine. I bought a tach signal kit from Autoworld MT, it is a 4-pulse.

    The tach doesn't work through the computer at all. It has its own wire.

    That being said, there is a spot on the computer that is for the tach signal, this is just to let the computer know what the rpms are so it can shift, etc. When I first did my conversion, I didn't run the tach wire to the computer, when I hooked up all the A/C components, I decided to run that wire since I wasn't sure if the computer needed to see engine speed to turn on the A/C.
    I found the 4 Pulse Tach kits on Destroked, Thanks! EDIT: Where did you mount the sensor for the 4 pulse tach kit? A picture would be much appreciated!END EDIT/.
    So '96 and up (Vortec motors) need a tach signal through the PCM to run the A/C? I'm pretty sure that '95 and below is not like that, which is definitely good news. The truck in question currently is a 1993 Suburban belonging to a friends mom (its been in their yard with a blown 454 for 3 years, and she was just notified that her new Expedition is going to be repo'd soon, and my friend took it upon himself to attempt a repower so she still has a fuel efficient daily driver. I'm excited, I get the 454 afterwards I'm definitely considering my own swap. I was just offered a 1996 K3500 Crew Cab Dually in a trade, but after this talk about the wiring being different and a PCM being required, I think I'll pass, unless I can adapt the 1995 Cluster into the 1996 truck and avoid the PCM. I cannot stress enough how much I truly HATE computer controlled ANYTHING on a vehicle. I'm going to shoot for a 1988-1995 K3500 Crew Cab Dually, or a 88-93 Suburban K2500 for my own swap. But Thank you for the info its helped alot, and by the way, so did you build threat, NICE work, I think I'll be stealing that hood latch idea, what is that striker made of?

    Quote Originally Posted by domepiece1 View Post
    I talked to dakota digital before and it sounded really expensive especially when you can go to best buy and buy a tomtom or garmin and have a extremely accurate GPS speed reading, directions, and a accurate mileage account for around $200 or less.
    There's an App for that ya know. I'm going for the whole "everything works like it did from the factory" deal.

    Quote Originally Posted by CumminsBronco View Post
    I swapped a 95 5.9 and 241dhd into my 97 suburban. On the speed sensor this is what I did.....Remove the Dodge tail housing and speed sensor ring (the ring looked just like a speedo ring on the tailshaft of an old manual transmission). My Sub had a 241 transfercase also. (whichever one GM uses, but it was a 241) Removed the tailhousing from the GM case, and also removed the tone ring from its' output shaft. Placed the GM tone ring on the Dodge output shaft and then placed the GM tailshaft housing onto the Dodge 241dhd. Used the GM VSS and seems to work just fine. I haven't driven it at highway speeds yet, just up and down the driveway and around a couple open acres, but all seems good so far.
    ..............I don't know if the 93 GM t-case and my 97 GM t-case are the same, but the output shaft of the Dodge 241dhd was the same as my 97 GM....as far as the Dodge speedo gear and the GM tone ring swapping out.
    Interesting. Are the tone rings available from any driveline shops, that you know of anyways? In case we're missing certain parts. I'm sure I can purchase the correct output shafts and so on and so forth.
    Last edited by 93FatBottom; 11-22-2011 at 06:37 AM.

  11. #10
    Registered User
    Join Date
    Oct 2010
    Location
    Gig Harbor, WA
    Posts
    226
    Thanks
    0
    Thanked 1 Time in 1 Post

    Default

    Quote Originally Posted by 93FatBottom View Post
    I found the 4 Pulse Tach kits on Destroked, Thanks! EDIT: Where did you mount the sensor for the 4 pulse tach kit? A picture would be much appreciated!END EDIT/.
    So '96 and up (Vortec motors) need a tach signal through the PCM to run the A/C? I'm pretty sure that '95 and below is not like that, which is definitely good news. The truck in question currently is a 1993 Suburban belonging to a friends mom (its been in their yard with a blown 454 for 3 years, and she was just notified that her new Expedition is going to be repo'd soon, and my friend took it upon himself to attempt a repower so she still has a fuel efficient daily driver. I'm excited, I get the 454 afterwards I'm definitely considering my own swap. I was just offered a 1996 K3500 Crew Cab Dually in a trade, but after this talk about the wiring being different and a PCM being required, I think I'll pass, unless I can adapt the 1995 Cluster into the 1996 truck and avoid the PCM. I cannot stress enough how much I truly HATE computer controlled ANYTHING on a vehicle. I'm going to shoot for a 1988-1995 K3500 Crew Cab Dually, or a 88-93 Suburban K2500 for my own swap. But Thank you for the info its helped alot, and by the way, so did you build threat, NICE work, I think I'll be stealing that hood latch idea, what is that striker made of?
    It bolts to the block, I'll see if I have any pics or I will take one.

    I am not 100% on the Vortec computer needing the tach signal for the A/C but I was having issues getting it working so I just wanted to eliminate stupid things like that. Plus it doesn't hurt to have the tach signal to the computer.

    The striker is the center piece of an exhaust clamp cut out, you'll figure it out when you see this:



    Thanks for the compliment, I really am happy with how it came out.

    If you need a 454 Vortec for your 96 truck, I still have mine but I am probably to far away from you.
    1996 Suburban 454 to 6BT Conversion.
    http://www.4btswaps.com/forum/showth...d-up-with-pics

  12. #11
    '69 FJ55 Land Cruiser dieselcruiserhead's Avatar
    Join Date
    Jan 2007
    Location
    Park City, Utah
    Posts
    1,659
    Thanks
    0
    Thanked 1 Time in 1 Post

    Default

    Which NV4500 are you using, the 23 spline or the 29 spline output? I bought both Dodge and Chevy NP241s (passenger side drop -- so a slightly different application) but I found the input gears in the t cases to be interchangeable. I could also split and rebuild one of these in 30 minutes. they are really really easy to figure out and deal with.

    I was happy with the NP241s and it held up fine in a heavy land cruiser with a juiced up 4BT including heavy wheeling on 35's. But if it were me I would just start off right and use something like a NP271 if it were me.
    1991 Toyota Pickup, Mercedes 300D OM617 diesel
    1969 Land Cruiser project in progress with 4BT
    1989 Land Cruiser project in progress with 4BT
    2010 KTM 450

    Successfully installed 4BT, Isuzu 4BD1T, and Mercedes 300D engines into different vehicles.

  13. #12
    Registered User
    Join Date
    Mar 2011
    Location
    Simi Valley, CA
    Posts
    27
    Thanks
    0
    Thanked 0 Times in 0 Posts

    Default

    Quote Originally Posted by Crummins View Post
    It bolts to the block, I'll see if I have any pics or I will take one.

    I am not 100% on the Vortec computer needing the tach signal for the A/C but I was having issues getting it working so I just wanted to eliminate stupid things like that. Plus it doesn't hurt to have the tach signal to the computer.

    The striker is the center piece of an exhaust clamp cut out, you'll figure it out when you see this:



    Thanks for the compliment, I really am happy with how it came out.

    If you need a 454 Vortec for your 96 truck, I still have mine but I am probably to far away from you.
    Interesting, thats something I should definitely look into then.

    I love how you ground down that exhaust clamp, someones smart! If the truck ever does blow up I could give you a buzz, but I do believe you're in
    Washington? I'm in Southern California, thats a bit of a drive but hey, who knows, right? My only issue I've come across is deciding what truck to do the swap in. I had my heart set on a Suburban, and Saturday I'm actually going to look at a 1993 Suburban K2500 with a 454, 120k miles, 10k on a new top end, with low oil pressure and coolant in the oil, not a scratch or dent, no paint peel ANYWHERE, no rust, and flawless interior. 800 bucks, how can I lose? I also have someone coming to look at my Dually on Saturday, for 3000, so we'll see what happens. Maybe I'll have enough My Sunday morning to go pick up a donor truck and get my swap started! My Issue is I have a Lance Cab over camper, been trying to trade for a travel trailer for a while, but no bites, and I have no where to park it either.. We'll see what happens I suppose.

    Quote Originally Posted by dieselcruiserhead View Post
    Which NV4500 are you using, the 23 spline or the 29 spline output? I bought both Dodge and Chevy NP241s (passenger side drop -- so a slightly different application) but I found the input gears in the t cases to be interchangeable. I could also split and rebuild one of these in 30 minutes. they are really really easy to figure out and deal with.

    I was happy with the NP241s and it held up fine in a heavy land cruiser with a juiced up 4BT including heavy wheeling on 35's. But if it were me I would just start off right and use something like a NP271 if it were me.
    Its a 29 spline, the gassers were 23 spline. The 5 speed came in the doner truck running and driving. I'm gonna get my first whack at building a transfer case with this swap, my buddy doesnt know how to do it and he asked me to do it when the time comes, so we'll see how easy I pick up on it huh? For simplicity of install, keeping everything stock as possible is the important thing here. Theres always an upgrade option in the future right?

  14. #13
    Registered User
    Join Date
    Nov 2008
    Location
    Floyds Knobs, In
    Posts
    244
    Thanks
    0
    Thanked 0 Times in 0 Posts

    Default

    93Fat......about the "tone ring".....do you have the 241 that came in the Chevy? My K1500 had the chevy 241 but I don;t know if your 2500 came with a 241 or something else. Maybe I should reiterate what I did. My donor truck had the nv4500 and Dodge version 241dhd.....29 spline input. I took the tailshaft housing and "speedo" ring off of the chevy 241 and swapped both those parts onto the dodge 241. That way, I was able to use the VSS that came on the chevy, now the factory speedo works. I did not have to change the output shafts.......referring to your statement that if you did that you would have a weak output shaft.......you don;t have to change the outputs. I drove the burb on the street for the first time last night......put 12 or so miles on it and the speedo works fine. (checked it to a gps) I never would have thought the a K1500 smallblock truck with a 241 would have the same output shaft in the T-case as a 1 ton dually Cummins Dodge.........but............they do, or did.

  15. #14
    Registered User
    Join Date
    Mar 2011
    Location
    Simi Valley, CA
    Posts
    27
    Thanks
    0
    Thanked 0 Times in 0 Posts

    Default

    Quote Originally Posted by CumminsBronco View Post
    93Fat......about the "tone ring".....do you have the 241 that came in the Chevy? My K1500 had the chevy 241 but I don;t know if your 2500 came with a 241 or something else. Maybe I should reiterate what I did. My donor truck had the nv4500 and Dodge version 241dhd.....29 spline input. I took the tailshaft housing and "speedo" ring off of the chevy 241 and swapped both those parts onto the dodge 241. That way, I was able to use the VSS that came on the chevy, now the factory speedo works. I did not have to change the output shafts.......referring to your statement that if you did that you would have a weak output shaft.......you don;t have to change the outputs. I drove the burb on the street for the first time last night......put 12 or so miles on it and the speedo works fine. (checked it to a gps) I never would have thought the a K1500 smallblock truck with a 241 would have the same output shaft in the T-case as a 1 ton dually Cummins Dodge.........but............they do, or did.
    So you just used the tailshaft housing and ring from the chevy 241 and everything bolted up? No clocking rings, no modification/fabrications? If so, then it might be more cost effective to do that then buy the input shaft and clocking ring and what not...

  16. #15
    Registered User
    Join Date
    Nov 2008
    Location
    Floyds Knobs, In
    Posts
    244
    Thanks
    0
    Thanked 0 Times in 0 Posts

    Default

    that's correct. The tailshaft housing and "tone ring" from my Chevy 241 swapped right onto the Dodge 241DHD. Nothing required. The Chevy VSS of course, bolts right back on the Chevy tail housing.

+ Reply to Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts