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392 Manual Transmission

2nd 392

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Well we do get the same trans as 650hp bmw’s.
Trans wouldn’t be an issue, the 4Auto computer controlled front axle engagement only after sensing rear traction loss, not full time AWD would be for this application.
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Bzinsky

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When the computer senses rear wheel traction loss and engages the front axle. On a standing start dumped clutch the rear end could likely be toast before the front is engaged .
It’s based on throttle position and slip

There is not even a milisecond that full power is sent to just the rear during a launch.

actually I don’t know if it’s based on slip at all, I would just assume it’s also based on slip. I do know the throttle position and speed is the primary call for power to the front. The front axle is always engaged, it merely sends variable power to the front via clutch, just like an awd system.

4auto is definitely awd if you define awd as having a center differential and 4wd having a locked tranfer case
 

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It’s based on throttle position and slip

There is not even a milisecond that full power is sent to just the rear during a launch.
Correct—with auto trans, why I specified a “dumped clutch” where the rear end could instantly fail before the system reacts. Somebody has to build one and and try it, volunteers? 😁
 

2nd 392

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It’s based on throttle position and slip

There is not even a milisecond that full power is sent to just the rear during a launch.

actually I don’t know if it’s based on slip at all, I would just assume it’s also based on slip. I do know the throttle position and speed is the primary call for power to the front. The front axle is always engaged, it merely sends variable power to the front via clutch, just like an awd system.

4auto is definitely awd if you define awd as having a center differential and 4wd having a locked tranfer case
The 4Auto is confusing. As I recall reading power is sent to the rear unless traction loss is sensed, then the clutch engages the front. On my AWD GC power is sent to the front end at 50/50, 60/40, or 70/30 percent, Mode dependent ( snow, tow, track, etc)
 

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The 4Auto is confusing. As I recall reading power is sent to the rear unless traction loss is sensed, then the clutch engages the front. On my AWD GC power is sent to the front end at 50/50, 60/40, or 70/30 percent, Mode dependent ( snow, tow, track, etc)
It was tested on the 4xe forums (same transfer case and transmission). The vehicle starts sending power to the front at 30% throttle regardless of traction.

So pretty much on the street it’s only activated by throttle position.

if you’re in mud/sand/snow you could spin the tires with less than 30% throttle. I’d assume it activates the front when it sees slippage as well, but it will never see rear only slippage on the street. More importantly, it will never send even close to the full power of the v8 to the rear axle (except possibly at higher speeds, which isn’t going to stress the diff)

On the flip side, when we factor in that during a full throttle launch, the rear probably provides 90% of the traction, which in turn means 90% of the power is actually going through the rear diff. But it would not be subject to the extreme stresses of the driveline shock during a clutch dump, which is mostly just the inertia of tires trying to match the intertia of the engine.
 
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2nd 392

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T
It was tested on the 4xe forums (same transfer case and transmission). The vehicle starts sending power to the front at 30% throttle regardless of traction.

So pretty much on the street it’s only activated by throttle position.

if you’re in mud/sand/snow you could spin the tires with less than 30% throttle. I’d assume it activates the front when it sees slippage as well, but it will never see rear only slippage on the street. More importantly, it will never send even close to the full power of the v8 to the rear axle (except possibly at higher speeds, which isn’t going to stress the diff)

On the flip side, when we factor in that during a full throttle launch, the rear probably provides 90% of the traction, which in turn means 90% of the power is actually going through the rear diff. But it would not be subject to the extreme stresses of the driveline shock during a clutch dump, which is mostly just the inertia of tires trying to match the intertia of the engine.
This is why it’s confusing. I have read (manual or other official source) the power is sent to the rear unless traction loss. The GC manual specifies the mode dependent power percentages. This should be more clearly defined by Jeep, or easier to find if it is somewhere. Nevertheless—lf a V6 Bronco gets a D50 I stand with my at least a D50 for the 392 opinion. 😁
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