8spd swap questions

[NitroHvy]

Hi,
First time posting, long time reader and yeah, I have read most of all the 8spd swap threads, I think.


My question is what year 8HP70 do I buy? My truck: 2013 Ram 1500 5.7L 4WD Quadcab tradesman/ST 6’4” bed
6spd auto (65rfe)


I understand ‘some’ 2013’s came with 8spd’s. Maybe my truck is wired for it?
Would I order a 2013 8spd or look for the newest edition in a 2018? Will any year 4th gen 8HP70 fit?


I really need to make this swap.

My truck is lifted 6” running 35’s on 20’s.

Again, 4WD.

I have been running a Diablosport Platinum EX Trinity tuner since 2017

I am currently replacing the VB and shift solenoid pack on the 6spd.

I’d like to gather the parts and make this swap for the 8spd this spring.

I’m in central Oregon.

I am not an auto mechanic but I do think I am a decent mechanic. I am an electrician of 25yrs and been wrenching on motorcycles for years but not really ever truck mechanic stuff.

I can afford to pay someone to install but it seems doable to me as a DIY.
I have other transportation.
I do not have a large shop or many auto specialty tools.
I’m ready to supercharge the 5.7L and beef up internals and push it with an 8spd!

You guys make it look easy. It’s not but it sure seems obtainable.


Where do I start? What year 8HP70 am I looking for?

I’m my truck indeed is wired, I would NOT need SGA’s kit? I know nothing essentially.

I am seeking advice.

Thank you for offering your knowledge and direction.

Nitro

 

[Wild one]

Try to hunt up a 15 or later 8 speed,as they're a bit easier to tune then the 13/14 8 speeds.Odds are you'll have to swap to HP tuning to tune the transmission though,especially if you end up with a 13 or 14 8 speed,as they aren't really tune-able via Diablo. How much are you planning on pushing through the transmission, the 8 speed with a "good" transmission tune will handle about 650 hp,but i wouldn't really be using it as a daily driver at that point,up to about 600 rwhp is where it'll last as a daily driver,with a "good" transmission tune. Why not hunt up a 6.4 and build it,instead of your 5.7,the 6.4 has a better crank,and if you're doing pistons and rods on the 5.7,why not do them on the 6.4 instead,plus if you find a 6.4 truck engine,you get the good BGE block,and basically a set of Hellcat heads,if you throw the better hellcat valves in it. Read this article,and you might see the benefit to stepping up to a 6.4.

We Scored a $400 Junkyard 392ci Hemi From a Ram Truck—and It’s the Mother Lode!

Our 392 BGE Hemi build-up journey starts with buying a mysterious junkyard Ram Truck 392 Hemi core. We crack it open and find the mother lode!

www.motortrend.com

 

[NitroHvy]

Oh man, well now you’re talkin! Yeah, I do like that idea. I have only been considering building the 5.7 because it’s got 80k on it and the 65rfe has 155k and needs some love. However, I do see your point and it could be valid.

Maybe I’ll just get the 6spd back up to better than it was with the new beefed up VB and switch to HPTuners and tune it better and just search for a 6.4 to mate to an 8HP70 and that would give me some more time. Although, it would require a bit more. Right? New harness for the 6.4 or just new PCM?

Putting it all together and dropping it in as one built unit would be a dream. I do like this idea!

Ok, educate me but I have seen numerous yt guys stating the 5.7L Hemi can handle upwards of 7-8lbs boost FI whereas the 6.4 is not designed for boost stock.

Yes, I plan to forge internals on the 5.7L so maybe this is a moot point. The 6.4 has a forged crank.

I like the idea of making the small block as torquey as I can. Then again, I suppose the 6.4 makes more torque stock but boosted? Which is cheaper to boost? Hmm.

My plan is to install a torquey cam and forge the internals and delete mds and and add SC.

The 5.7L runs great currently. Will it eventually eat a cam up when a lifter fails? Maybe. My 2013 engine did at 69,900mi. Just shy of Dodge America’s warranty!!!!!! They wanted to rebuild the top end and I said no. Had my extended warranty source a Texas ‘16 5.7 wrecker and it worked out great.
So my 5.7L in my ‘13 is a ‘16.


At 155k on the 65rfe I just lost the trans. Well, it runs but codes P0734 and will not find 4th and will hunt then send to limp mode. The VB and shift solenoid pack will cure for awhile.

Maybe I build a motor I can hang in the shop and attach the trans too! While still enjoying the 5.7L but I’m ready for POWER and crispy shifts!

Sorry man, got off track

 

[Wild one]

You don't need a new PCM or harness for a 6.4,just tune the pcm you have,same as you would if you boost your 5.7.They're basically identical engines ,as far as bolting it into the truck,or adding aftermarket external go-fast goodies,like headers/ blowers etc,the only differance would be the cams,the 6.4 being more cubes will handle a bigger cam then the 5.7 will and still be street-able.If you're thinking smallblock,both engines are classed as smallblocks,as they're both the same size externally.Be the same as looking at an old school 340 and 360,they're both classed as smallblocks,but one has more cubes then the other. Both engines need pistons and rods to be reliable with boost,so there's no differance there,but the 6.4 has a stronger crank then the 5.7 has. If your 5.7 is still in good shape,you can sell it after the swap and recoup some of your investment.