Hellcat 8HP95 transmission in an SRT?

[Buckshot_Brian]

Has anyone put the 8HP95 transmission, transfer case, rear differential (w/cradle), and starter out of a Hellcat or Trackhawk into their Durango SRT 392? Assuming everything bolts up ok, are connectors the same, and what about TCM programming?

I installed a Whipple Gen V supercharger kit on my 2021 a year ago.. pushing 638HP and 565 ft/lbs torque.. been running great, however the stock 8HP70 is finally protesting. First developed a minor shift flare going into 3rd.. which remained unchanged for 2-3 months. Yesterday started driving about 10 mph down driveway.. went to accelerate and engine revved but tranny "slipped" (car wouldn't accelerate) and check engine light immediately came on along with "service transmission" message. Tried driving down road but transmission would no longer shift, so turned around and parked it.

Not sure if some glitch in the TCM, or some other failure at this point. Car only has 45,000 miles on it. I have an extended warranty, but pretty sure dealer will say "no way man" when they see Mr. Whipple lurking under the hood. Towing to my buddies transmission shop tomorrow for evaluation.

My options seem to be: 1) Try to get warranty thru dealer, 2) Rebuild stock tranny with one of the high performance kits (unless some minor glitch causing issue), or 3) Do the Hellcat/Trackhawk drivetrain swap (have access to this for $9000).

Thanks for reading, hope to hear from others who may have traversed this path.

 

[Smitty]

@hellno
Adding the trans expert

 

[hellno]

At that power level a well built and TUNED 8hp 70 should be fine

 

[jonx96]

As @hellno said above a built trans will be fine. One of the scat pack challengers I tune is going through the process right now. If you end up doing the switch be very careful who you choice. He went with hellrazein (charles) or whatever its called and waited months for the trans. Kept getting the run around. Call @hellno real honest guy wont stear you wrong. Make sure you have a good trans tune.

 

[Marc W]

SpankinTime Motorsports just did one in a customer’s Scatpak Charger. Built 392 with a 3.0 Whipple making 1100whp now. He ran 9.3 at 150 full weight. It wasn’t a simple switch and involved a bit of trickery to fool the pcm to accept it as her own.

 

[hellno]

SpankinTime Motorsports just did one in a customer’s Scatpak Charger. Built 392 with a 3.0 Whipple making 1100whp now. He ran 9.3 at 150 full weight. It wasn’t a simple switch and involved a bit of trickery to fool the pcm to accept it as her own.

I’m surprised the difference in gear ratios don’t cause an issue

 

[hellno]

At that hp it makes no sense to change and go through the headaches of that swap save the money and just have it built and tuned , I would never recommend that to my customers just to make an extra buck

 

[Marc W]

I’m surprised the difference in gear ratios don’t cause an issue

Also changed the rear to a 3.09. There’s that rule we keep running into. Every time you do something significant, you then have to do two other things because of it. Snowballs from there 😂

 

[hellno]

Also changed the rear to a 3.09. There’s that rule we keep running into. Every time you do something significant, you then have to do two other things because of it. Snowballs from there 😂

Tell it 😁

 

[Marc W]

In our case it was much more cost effective to take one of a number of hp90’s parked in a corner of the shop and transplant it when you know how to do it, than to pay someone else to build a 70 to take that hp at that weight. David…. Is it even possible (within reason) to build a hp70 to the 1100whp/4700lb level? Not that that applies to the op but considering we hijacked his post already 🤓

 

[Marc W]

9.31 @150 on a 6 rib serpentine belt at 4700 lbs. Hp90 trans with a 3.09 gear.

 

[hellno]

It is much more cost effective to take one of a number of hp90’s parked in a corner of the shop and transplant it when you know how to do it, than to pay someone else to build a 70 to take that hp at that weight. David…. Is it even possible (within reason) to build a hp70 to the 1100whp/4700lb level?

he said he’s at 638 Hp marc , at that level an hp70 would be fine now if he goes above 900 then yes I agree with you but I can promise you this it will cost him well above 9k to swap to the 90 and he’ll have to be without his Durango for a good period of time and I’d be willing to bet money he’ll regret it in the long run

 

[Marc W]

I kinda skipped over the 638 part when he said 3.0 Whipple. 😂. I guess another question would be… wasn’t it kind of a rule that one shouldn’t supercharge the NA Hemi’s without doing internals? 😳

 

[hellno]

I kinda skipped over the 638 part when he said 3.0 Whipple. 😂. I guess another question would be… wasn’t it kind of a rule that one shouldn’t supercharge the NA Hemi’s without doing internals? 😳

mar that hp I’m assuming he’s not pushing that much boost so I’d imagine it’s probably fine

 

[hellno]

Since

Has anyone put the 8HP95 transmission, transfer case, rear differential (w/cradle), and starter out of a Hellcat or Trackhawk into their Durango SRT 392? Assuming everything bolts up ok, are connectors the same, and what about TCM programming?

I installed a Whipple Gen V supercharger kit on my 2021 a year ago.. pushing 638HP and 565 ft/lbs torque.. been running great, however the stock 8HP70 is finally protesting. First developed a minor shift flare going into 3rd.. which remained unchanged for 2-3 months. Yesterday started driving about 10 mph down driveway.. went to accelerate and engine revved but tranny "slipped" (car wouldn't accelerate) and check engine light immediately came on along with "service transmission" message. Tried driving down road but transmission would no longer shift, so turned around and parked it.

Not sure if some glitch in the TCM, or some other failure at this point. Car only has 45,000 miles on it. I have an extended warranty, but pretty sure dealer will say "no way man" when they see Mr. Whipple lurking under the hood. Towing to my buddies transmission shop tomorrow for evaluation.

My options seem to be: 1) Try to get warranty thru dealer, 2) Rebuild stock tranny with one of the high performance kits (unless some minor glitch causing issue), or 3) Do the Hellcat/Trackhawk drivetrain swap (have access to this for $9000).

Thanks for reading, hope to hear from others who may have traversed this path.

Have your buddy at the transmission shop buy a gpz clutch and steel set up,along with a new pump ( always put a new pump in ) and have him refresh it at that power level a stock clutch set up will do just fine unless your planning on adding more power , then make sure it’s tuned properly (hopefully your on hp tuner ) if you need help reach out to jonx96 he can get the trans tuned

 

[Buckshot_Brian]

@hellno
Adding the trans expert

Thanks Smitty 🙂

 

[Buckshot_Brian]

Thanks Smitty 🙂[/QUOTE

At that hp it makes no sense to change and go through the headaches of that swap save the money and just have it built and tuned , I would never recommend that to my customers just to make an extra buck

At that hp it makes no sense to change and go through the headaches of that swap save the money and just have it built and tuned , I would never recommend that to my customers just to make an extra buck

Thanks hellno, appreciate your expertise in pointing me the right direction.

 

[Unholy707]

Isn’t the 8hp95 the AWD trans?
Edit: somehow missed OP drives a Durango. Stupid small phone screen

 

[Jimmy N.]

Isn’t the 8hp95 the AWD trans?
Edit: somehow missed OP drives a Durango. Stupid small phone screen

No forum is perfect. Lots of multi-door owners here.

 

[drag racer]

I'll be up to "10 doors" in my shop come this weekend when the nice delivery man with a 90-foot rig shows up ;-)