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8 spd swap

35K views 89 replies 17 participants last post by  TRusselo 
#1 ·
I took a look around the forum and didn’t see anything in the titles, if it’s been covered in another swap thread my apologies but this probably deserves its own thread.
Anyone done this yet? With controllers coming out I’m guessing it’s a matter of time (Sound German Automotive has one). My question is how much of a direct swap is it nuts and bolt wise for a 4wd? I’m guessing it would be pretty straight forward as the 4th gens used the 65rfe and then switched to 8hp70 and I don’t imagine them moving t cases around and altering driveshaft lengths so I’m guessing the 4wd 65RFE and the 4wd 8 speed would be the same length wise, I’m also pretty sure they kept the same t case when they switched over as well so they should be the same on the tail end. As the 65 and 545 are virtually the same, I’m guessing it would pretty much be a bolt in affair for older trucks? They switched from the NP/NV t case to a Borg Warner at some point in 4th Gen rams, but I think they bolt to the tranny the same, so I think the NP/NV t case in my 2005 should bolt to a 8hp70. This is all speculation so I’m wondering if anyone has an 8hp70 to measure up so I can compare it to a 545 I have in my garage (overall length and the t case adapter bolt pattern)
 
#3 ·
Contact sound German, last I heard they were testing out 1 or 2 rams with the swap, that was a few months ago. I heard the controller is about a grand, other then that the swap should be cheapish if you find a deal on a used, good condition trans. Seems like the hold 500 hp ok stock. I know a few racing guys have started breaking them. I think they also switched to a flanged yoke on the drive shaft instead of a slip fit, don’t quote me though
 
#5 ·
If it’s a bolt in affair then I can’t see it being ridiculous expensive. There’s used Ram 8hp70’s on eBay for 800-1000. Sound German charges $1000 for the controller. You’d have to get your PCM flashed to a manual trans or find one so another $400 there, another $600ish for incidentals and I think you could do it for 3Kish. I know there was some quotes being priced of 10K being thrown around for a NAG1 swap at a shop but since the 8 spd is a truck trans that may bolt in, if you did it yourself I don’t think I’m far off? They stand up to 6.4’s pretty decently and I know if you put big power to them they need help but for 99% of guys just wanting something more stout and can handle 600ish hp and better driving than a 545 maybe it’s a good option
 
#7 ·
IMO a 8spd 3rd gen would be bad a$$...
 
#20 ·
:iagree: 2 of my sons have Rams with the 8speed. They are pretty bad *** for a factory truck. So a built 03 would be real nice.:thumb:
 
#8 ·
Had a lengthy conversation with Russell Drake [russell@soundgermanautomotive.com] about this. $1000 for the harness. Then you just need a trans, an electronic shifter (not the rotary) and since the 8HP70 has a flange you'll need a custom 2 piece or slip driveshaft for 2wd (4wd is an easier swap). Most likely need a manual PCM flash since the PCM would probably lose it's sh!t without the trans inputs. Definitely not a bolt in, but not difficult; just a bit pricey altogether. Considering the interior swap I just did (and it's getting into boating season) the RFE will have to last a bit longer before I drop an easy $2000 or more. Last email I got from them:


Hello,
You are receiving this email because you have contacted me about an 8hp standalone setup. I will have 8 of these in next week and depending on the day they show up I may be able to ship late next week or late the following week. I am taking orders first come first serve. I know some of you have already contacted me and it is just to much of a list to keep track of. So here we go. I need your billing and shipping address. Your phone number. And what engine, and control unit you are using for the engine. Ie Mopar Crate or factory take out of salvage car that is being reprogrammed for standalone use. Basically factory computers that have factory CAN messages as a production car would have. I also can support older 5.7 and 6.1 CAN as in a lx platform with the NAG1. I would need to know that. Also the shifter wiring is for the T handle floor shifter, not the Rotory knob. If you send me a Rotory knob connector I can install it on the harness for you at no extra charge.
Again, first come first serve. I will do my best and I will not have a huge lead time on getting more. I will reorder probably next week for the next batch. So dont panic if you do not get in on these. If you have any questions now or upon receiving an invoice please do not hesitate. Price will be 1000.00..

Thank you.


--
Russell Drake
Sound German Automotive
425-503-9233
soundgermanautomotive.com


And just to make things more interesting, there is a shop down in FL (Hellraiser Performance) that has figured out how to do successful 8HP90 swaps (in place of a 70). So I imagine once swapped, if you're making huge power you can swap to one of those (if necessary) fairly easily.
 
#9 ·
That is excellent information.. thanks for posting it.
 
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#11 ·
I don’t see why you would need a 3rd gen pcm reprogrammed to manual, UNLESS you have to have no codes for emissions. It should be the same as any other manual swap we have been doing as far as the pcm goes. Am I understanding it correctly that the sound German harness has its own controller?
 
#15 ·
No, it has its own OBD port basically; the ZF's have internal TCM's


I agree, if the SG is stand alone. It doesn't matter. Actually that is a bit of a redflag with them not knowing that.

He's never dicked with a 3rd gen PCI bus Ram, I asked just out of curiosity. I imagine whatever you guys have done with the 46 swaps would do the trick. The harness simply gets wired in to what inputs it needs, then HP tuner the trans TCM.


Sounds reasonable, having a DTC's in some states are a problem.

That's what MD's emissions program is wholly based on lol; any kind of code fails you. My Magnum had a partial TCM failure and it was throwing a U code (loss of communication) and while it had nothing to do with emissions whatsoever, it failed until I figured out what was wrong (something the friggin dealer couldn't figure out).
 
#12 ·
I agree, if the SG is stand alone. It doesn't matter. Actually that is a bit of a redflag with them not knowing that.
 
#13 ·
Sound German Automotive has been around for awhile. He originally did his NAG1 controller, valve body etc (he claims his valve body with his programming on a stock NAG1 is good for 700+ and he has the swaps to back it up). He got into the 8 speeds a few months back and has currently swapped a 5.7/8 spd into a late 70’s Ford 1/2 ton lol. The fact that he doesn’t, apparently, know that you don’t HAVE to reflash a Gen 3 Ram controller really doesn’t upset me to much, as I imagine he hasn’t worked with that particular computer much (why would he? Our trucks never came with NAG’s). Or maybe he does and doesn’t want to put up with complaints of a check engine light.
 
#14 ·
Sounds reasonable, having a DTC's in some states are a problem.
 
#16 ·
just think how one of these Rams would launch with the Demon/1320 Challenger Trans brake ZF trans in it...………...
 
#17 ·
I think the first gear in the 46rh is something like 3rd or 4th in the 8spd...
 
#19 ·
46rh
1st - 2:45
2nd - 1:45
3rd - 1:00
4th - .069
 
#22 ·
Trailer pulling gear...
 
#25 ·
I'm doing this right now with MMX. Putting the Hellcat engine in front. It took finding a salvaged truck for the parts to keep cost down. The problem with going with the independent controller by German with this swap is there's no torque management. The 8hp70 won't last long without it. Once the 8hp70 is in place the right way, then you can put the 8hp90 in. Chuck @Hellraiser has got that figured out.
 
#27 ·
Wasn't my first choice of engines considering I spent for a forged balanced blueprinted stroker with the whipple on top with all the side dishes. HELLCAT 6.2 engine in these trucks has done by Dakota customs. Rebel as a matter of fact. It's a good read.
Ultimate Mopar Swap- Installing a 700hp Hellcat Crate Engine in a 2017 Ram Rebel
http://www.trucktrend.com/how-to/en...0hp-hellcat-crate-engine-in-a-2017-ram-rebel/

But Matt@moes has the setup! Baby steps. They'll never be a 4th gen again. Love the body style.
 
#34 ·
This has been my latest fascination. I have talked to Sound German, I already have the manual 05 PCM, I possibly have the hp70 (2wd truck versions are not easy to find up here), and the most research for me is going to be the shifter for it. I do not just want to install a simple dial and have no option for manual shifts so it's going to be a lot of figuring out which shifter I want and how I plan to mount it. Once I have determined that, Sound German will build the harness to work with it. Other than that it looks like a very simple install. Yeah it isn't cheap but after I bought a 2019 Classic with the 8 speed I am hooked. I had a 17 with the 6 speed which was basically the same as my 19 as it was a c/c 4wd and 3:91 gears, but the 19 would destroy it with that 8 speed.
 
#35 ·
This may not be of any help, but B&G were modifying shifters for the 8spd. You might contact them to see if they can be any help.
 
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