8hp70 tcm?

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Ram1683

Ram1683

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You can't go wrong with AlfaOBD and the OBDLink MX+ combo. Hands down the most versatile tool to keep in your tool kit for these Rams. Really any FCA/Mopar/Chrysler/Stallantis vehicle. I'll have a few cold ones in your honor and wish you the easiest of installs. Look forward to seeing how it goes so keep us posted!
absolutely will do. Appreciate all the info
 

t0ymach1n3

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I don't have my tablet in front of my, but that sounds about right. Sorry for the late reply.
 

WAR-RAM

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I don't have my tablet in front of my, but that sounds about right. Sorry for the late reply.
Was your TCM new and unprogrammed? I've tried to do a VIN write on mine and kept getting an error.
 

t0ymach1n3

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Was your TCM new and unprogrammed? I've tried to do a VIN write on mine and kept getting an error.
Nope. It was from a newer 2017 and was programmed for the truck it came from which I believe was a 2WD quad cab. I swapped it into the 2014 transmission (have no idea what the donor truck was) bolted in my RCSB and had zero issues.
 

Wild one

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Was your TCM new and unprogrammed? I've tried to do a VIN write on mine and kept getting an error.
When i replaced my 8 speed several years ago,i bought a brand new 8 speed from the dealer,and had to have it programmed / basically married to the truck. Had my dealer tech buddy bring the dealers scan tool over to my place,and he did it right on my driveway for supper and a case of beer,lol. At that time AlphaOBD wasn't really kicking around so i don't know it it'll work to program the TCM to the truck or not
 

WAR-RAM

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Nope. It was from a newer 2017 and was programmed for the truck it came from which I believe was a 2WD quad cab. I swapped it into the 2014 transmission (have no idea what the donor truck was) bolted in my RCSB and had zero issues.
Interesting. I haven't tried to start the truck yet, but I thought I read somewhere that a vehicle will not start if the PCM and TCM VINs didn't match. I have JSCAN which allows me to clear the VIN in the BCM, ABS and EPS, but not the TCM. I'm wondering if the VIN in the TCM even matter. I combed through Alldata searching for VIN mismatch diagnostics, and the only thing that came up were PCM, BCM, RADIO, RF HUB and ABS related. Nothing is mentioned about the TCM when it comes to the VIN. I guess I'll have to try to start the truck to see what happens.vin mismatch.JPG
 

t0ymach1n3

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Interesting. I haven't tried to start the truck yet, but I thought I read somewhere that a vehicle will not start if the PCM and TCM VINs didn't match. I have JSCAN which allows me to clear the VIN in the BCM, ABS and EPS, but not the TCM. I'm wondering if the VIN in the TCM even matter. I combed through Alldata searching for VIN mismatch diagnostics, and the only thing that came up were PCM, BCM, RADIO, RF HUB and ABS related. Nothing is mentioned about the TCM when it comes to the VIN. I guess I'll have to try to start the truck to see what happens.View attachment 514574
I used AlfaOBD to reset the VIN for the TCM. I've never used JScan before so I can't say what it could or couldn't do to resolve that. I do know I was able to do so with AlfaOBD and my truck has ran like a champ for months since I swapped the 2017 TCM into the 2014 8HP70 I'm using.
 
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Ram1683

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I used AlfaOBD to reset the VIN for the TCM. I've never used JScan before so I can't say what it could or couldn't do to resolve that. I do know I was able to do so with AlfaOBD and my truck has ran like a champ for months since I swapped the 2017 TCM into the 2014 8HP70 I'm using.
Off topic for a second And I think I asked you this before. You bypassed the warmer body completely when you did your install right?
 

t0ymach1n3

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Off topic for a second And I think I asked you this before. You bypassed the warmer body completely when you did your install right?
Sorry if I missed that. There are a number of ways to go about dealing with that tumor on the side of the trans. For me, I didn't so much bypass it completely as I took every part of it off the trans and tapped the holes that it used and ran my own AN fittings and lines to the condenser and called it a day.
 
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Sorry if I missed that. There are a number of ways to go about dealing with that tumor on the side of the trans. For me, I didn't so much bypass it completely as I took every part of it off the trans and tapped the holes that it used and ran my own AN fittings and lines to the condenser and called it a day.
No you didn't miss it, I'm pretty sure you had responded in the thread I made about the thermostat. My stressed out brain just forgot. Yours looks fantastic. Where did you find a tap that big? I just tapped and tread sealed the holes. Didn't install the trans yet so maybe I can still go you're route
 

t0ymach1n3

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Seemed like the easier yet solid route
Could be. And I have no opinion on how anyone chooses to do it nor am I looking at start a conversation about it. That's not the look nor the way I wanted to go, hence why I did what I did. If you want to yours the way you want, I fully support you in that choice.
 
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Ram1683

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Could be. And I have no opinion on how anyone chooses to do it nor am I looking at start a conversation about it. That's not the look nor the way I wanted to go, hence why I did what I did. If you want to yours the way you want, I fully support you in that choice.
Gotcha. Yours looks 100% better then mine. I'm just worried about tapping the case
 

t0ymach1n3

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Gotcha. Yours looks 100% better then mine. I'm just worried about tapping the case
It was a very slow and nerve racking process in trying to keep all the shavings out of the transmission. I've done it to 2 of them and neither have had an issue if you are slow and take your time. It for sure is not for the faint of heart. I'm pretty bold in taking on projects, even if i've got no clue what i'm doing. Like installing a Cresspo Hemiwing or doing an 8 speed swap in my apartment garage with nothing but basic hand tools and a floor jack :cool::laughing1:
 

lukaab

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Almost anything you do to these transmissions it will need to have a quick learn done on it. If that doesn't help I would check the shifting solenoid.
 
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