4x4 drivetrain limits; real world experiences?

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

GeauxinUp

Senior Member
Navy Badge
Joined
Feb 9, 2025
Posts
721
Reaction score
1,394
Location
Louisiana
Ram Year
2026 Limited
Engine
3.0L TT H.O.
I’m in the early stages of planning a 4th gen RCSB 4wd street build and trying to get realistic expectations on drivetrain limits outside of the engine and transmission (those are already planned).

Target is ~850–900whp on a turbo 6.2 setup.

I’m specifically trying to gather real-world info on:
• Front and rear differential strength
• Front CV/half shaft limits
• Transfer case (BW 44-45) durability under load
• Driveshaft limits (front + rear)
• Any known weak points in the 4x4 system at higher power

Would really like to hear from anyone who has actually:
• Run boosted setups in 4x4
• Launched on sticky tires
• Broken parts (what failed first, and at what power level?)

Also curious what people have upgraded vs left stock and how it held up.

Trying to keep it streetable (but will see some track time I'm sure), not a full race setup.

Appreciate any insight!
 
Last edited:

Wild one

Senior Member
Joined
Jan 17, 2016
Posts
23,721
Reaction score
54,482
Ram Year
14 Sport
Engine
5.7
You're on the wrong page,you want to be on the Hi-po facebook pages like Tuned Rams /High Performance Rams.
800 crank is do-able,but 900 rwhp is gonna cost you a $h!tload of money.You'll probably want to look into a 9" rear diff swap as there's not much available for the ZF diffs.
There's not much differance in the 6.2 block and the 6.4 block,they're both BGE blocks,you could start with any truck 6.4 block, with a valve and spring change it basically has Hellcat heads with a N/A intake manifold bolt pattern.
A 6.4 done up as a 411 is a fairly common platform.
The 44-44 supposedly will live up to about the 800 crank level,but at 900 rwhp is probably going to start giving you issues.
Get ahold of Jon Sipple to build you a 8HP70 to handle the power,and see what he reconmends you do with the transfer case.
The front diff i don't know if it'd live at 900rwhp or not.
I know Matt Fikac had well over $50,000 into his old truck,and that was several years ago,so you're probably looking at the same amount of money or more now.
You better have really deep pockets to build what you want and have some sort of reliability,as you're not gonna throw something like that together with cheap parts and expect it to live.
A back halved 2wd truck might be cheaper and easier to build,plus it'll have alot less parts to break or beef up
 
OP
OP
GeauxinUp

GeauxinUp

Senior Member
Navy Badge
Joined
Feb 9, 2025
Posts
721
Reaction score
1,394
Location
Louisiana
Ram Year
2026 Limited
Engine
3.0L TT H.O.
You're on the wrong page,you want to be on the Hi-po facebook pages like Tuned Rams /High Performance Rams.
800 crank is do-able,but 900 rwhp is gonna cost you a $h!tload of money.You'll probably want to look into a 9" rear diff swap as there's not much available for the ZF diffs.
There's not much differance in the 6.2 block and the 6.4 block,they're both BGE blocks,you could start with any truck 6.4 block, with a valve and spring change it basically has Hellcat heads with a N/A intake manifold bolt pattern.
A 6.4 done up as a 411 is a fairly common platform.
The 44-44 supposedly will live up to about the 800 crank level,but at 900 rwhp is probably going to start giving you issues.
Get ahold of Jon Sipple to build you a 8HP70 to handle the power,and see what he reconmends you do with the transfer case.
The front diff i don't know if it'd live at 900rwhp or not.
I know Matt Fikac had well over $50,000 into his old truck,and that was several years ago,so you're probably looking at the same amount of money or more now.
You better have really deep pockets to build what you want and have some sort of reliability,as you're not gonna throw something like that together with cheap parts and expect it to live.
A back halved 2wd truck might be cheaper and easier to build,plus it'll have alot less parts to break or beef up
Those are public groups, and I don’t like all these nosy f’ers around here knowing my business :D

I’ll be running an 80/89 turbo (Walker Induction) setup on a factory 6.2 H.O. long block, MMX double pump, whatever size injectors I’ll need, Sipple trans. All of that adds up to around $20k, there’s no way I’ll be even close to $50k, maybe half that.

Surprised to hear the clutches in the 44-44 can hold that much power. I’m planning on going with the 45, to avoid the clutches.

I’m not planning on just throwing some cheap **** together, hence the reason of being on here planning it all out.
 

Wild one

Senior Member
Joined
Jan 17, 2016
Posts
23,721
Reaction score
54,482
Ram Year
14 Sport
Engine
5.7
Those are public groups, and I don’t like all these nosy f’ers around here knowing my business :D

I’ll be running an 80/89 turbo (Walker Induction) setup on a factory 6.2 H.O. long block, MMX double pump, whatever size injectors I’ll need, Sipple trans. All of that adds up to around $20k, there’s no way I’ll be even close to $50k, maybe half that.

Surprised to hear the clutches in the 44-44 can hold that much power. I’m planning on going with the 45, to avoid the clutches.

I’m not planning on just throwing some cheap **** together, hence the reason of being on here planning it all out.
You'll find more fast guys on the facebook pages then on here,but if you've found John Sipple and Mike Walker,you're better off talking to them,then anybody on here or on facebook. Ask John what he reconmends you do for the t-case,and Mike will tell you what you should be doing to the engine to keep it alive and happy
I'm just going by what Matt Fikac of Moes said he had into his truck,so if you think he was out to lunch on what it cost him,take it up with him,not me,i'm just relaying what he said.
You'll probably want want to look into doing drop in rods and pistons into that 6.2 block if you want it to last for any length of time,as 900rwhp is pushing the stock Hellcat parts. 900 at the tire is gonna be 1,000 or more at the crank
 
OP
OP
GeauxinUp

GeauxinUp

Senior Member
Navy Badge
Joined
Feb 9, 2025
Posts
721
Reaction score
1,394
Location
Louisiana
Ram Year
2026 Limited
Engine
3.0L TT H.O.
You'll find more fast guys on the facebook pages then on here,but if you've found John Sipple and Mike Walker,you're better off talking to them,then anybody on here or on facebook. Ask John what he reconmends you do for the t-case,and Mike will tell you what you should be doing to the engine to keep it alive and happy
I'm just going by what Matt Fikac of Moes said he had into his truck,so if you think he was out to lunch on what it cost him,take it up with him,not me,i'm just relaying what he said.
You'll probably want want to look into doing drop in rods and pistons into that 6.2 block if you want it to last for any length of time,as 900rwhp is pushing the stock Hellcat parts. 900 at the tire is gonna be 1,000 or more at the crank
Thanks for the info. I’ve spoken to HHP and they said I’d be fine. This is the Demon 6.2 btw.
I’ll reach out to Sipple about the t-case

6.2L H.O. long block
 
OP
OP
GeauxinUp

GeauxinUp

Senior Member
Navy Badge
Joined
Feb 9, 2025
Posts
721
Reaction score
1,394
Location
Louisiana
Ram Year
2026 Limited
Engine
3.0L TT H.O.
You're on the wrong page,you want to be on the Hi-po facebook pages like Tuned Rams /High Performance Rams.
800 crank is do-able,but 900 rwhp is gonna cost you a $h!tload of money.You'll probably want to look into a 9" rear diff swap as there's not much available for the ZF diffs.
There's not much differance in the 6.2 block and the 6.4 block,they're both BGE blocks,you could start with any truck 6.4 block, with a valve and spring change it basically has Hellcat heads with a N/A intake manifold bolt pattern.
A 6.4 done up as a 411 is a fairly common platform.
The 44-44 supposedly will live up to about the 800 crank level,but at 900 rwhp is probably going to start giving you issues.
Get ahold of Jon Sipple to build you a 8HP70 to handle the power,and see what he reconmends you do with the transfer case.
The front diff i don't know if it'd live at 900rwhp or not.
I know Matt Fikac had well over $50,000 into his old truck,and that was several years ago,so you're probably looking at the same amount of money or more now.
You better have really deep pockets to build what you want and have some sort of reliability,as you're not gonna throw something like that together with cheap parts and expect it to live.
A back halved 2wd truck might be cheaper and easier to build,plus it'll have alot less parts to break or beef up
Btw...wait until you see what Matt is planning with his current build. If you thought the last one was expensive......
 
OP
OP
GeauxinUp

GeauxinUp

Senior Member
Navy Badge
Joined
Feb 9, 2025
Posts
721
Reaction score
1,394
Location
Louisiana
Ram Year
2026 Limited
Engine
3.0L TT H.O.
You'll find more fast guys on the facebook pages then on here,but if you've found John Sipple and Mike Walker,you're better off talking to them,then anybody on here or on facebook. Ask John what he reconmends you do for the t-case,and Mike will tell you what you should be doing to the engine to keep it alive and happy
I'm just going by what Matt Fikac of Moes said he had into his truck,so if you think he was out to lunch on what it cost him,take it up with him,not me,i'm just relaying what he said.
You'll probably want want to look into doing drop in rods and pistons into that 6.2 block if you want it to last for any length of time,as 900rwhp is pushing the stock Hellcat parts. 900 at the tire is gonna be 1,000 or more at the crank

Found an engine I think you'll be proud of...haha
I'll post it up when the deal is done!
 
OP
OP
GeauxinUp

GeauxinUp

Senior Member
Navy Badge
Joined
Feb 9, 2025
Posts
721
Reaction score
1,394
Location
Louisiana
Ram Year
2026 Limited
Engine
3.0L TT H.O.

Wild one

Senior Member
Joined
Jan 17, 2016
Posts
23,721
Reaction score
54,482
Ram Year
14 Sport
Engine
5.7
@Wild one
View attachment 583873View attachment 583874
Well you can't say it's not broke in,as that engine is famous :Big Laugh: What are you hanging off it for boost? Personally i'd get ahold of Mike Anthony Walker and talk to him about one of his turbo set-ups;)
 
OP
OP
GeauxinUp

GeauxinUp

Senior Member
Navy Badge
Joined
Feb 9, 2025
Posts
721
Reaction score
1,394
Location
Louisiana
Ram Year
2026 Limited
Engine
3.0L TT H.O.
Well you can't say it's not broke in,as that engine is famous :Big Laugh: What are you hanging off it for boost? Personally i'd get ahold of Mike Anthony Walker and talk to him about one of his turbo set-ups;)
Twin 58’s
 
Back
Top