Topic Sponsor
2021+ Ford F150 Discussion of the 14th generation F150.
Sponsored by:
Sponsored by: Real Truck

Auto 4wd

Thread Tools
 
Search this Thread
 
Old May 9, 2024 | 10:57 AM
  #41  
tigmd99's Avatar
Thread Starter
Senior Member
Liked
Loved
Community Favorite
 
Joined: Apr 2023
Posts: 331
Likes: 232
Default

Originally Posted by SALEEN961
For 2021 Alldata lists the base ESOF transfer case as a Borg-Warner 4469 and the TOD transfer case with 4A as a Borg-Warner 4467.
If so then it came on Ford F150 2015 and up. So definitely a more modern TC than 4417. This is what I found:

2-Speed Torque-On-Demand

The 2-speed torque-on-demand transfer case system consists of the following components:

- MSS , located on the instrument panel

- Transfer case assembly (includes shift motor and synchronization clutch)

- TCCM

The Borg-Warner 4467 2-speed torque-on-demand transfer case is a 2-piece magnesium design. The transfer case transfers engine power from the transmission to the front and rear axles. Vehicles equipped with the 2-speed torque-on-demand system allow the operator to choose between 2WD and 3 different 4WD modes. The transfer case is shifted electronically based on the MSS position. Under normal driving conditions, the unit is in 2WD (2H), but when desired, the operator may shift into 4WD high (4H), 4WD low (4L) or 4WD AUTO (4A). When shifting into or out of 4WD (4L) range, the TCCM requires that the vehicle speed is less than 5 km/h (3 mph) and the transmission is in NEUTRAL.

The transfer case is equipped with an electronically controlled high torque capacity clutch which is located inside the case. This clutch is used to synchronize the speed of the front driveline with the rear driveline during 2WD (2H) to 4WD high (4H) or 4WD AUTO (4A) shifts. The clutch also provides torque to the front driveline in all 4WD modes. The transfer case is lubricated by a positive displacement fluid pump that channels fluid flow through holes in the rear output shaft.
Reply
Old May 9, 2024 | 07:46 PM
  #42  
akulahawk's Avatar
Senior Member
 
Joined: Oct 2021
Posts: 202
Likes: 123
From: Sacramento, CA
Default

Originally Posted by tigmd99
I don’t understand the need to say that 4A mode is something other than a on-demand AWD. Yes, it has transfer case with 4Hi and 4Lo. But in 4A mode, it is basically a rear-bias AWD type system…and literally acts like any other on-demand AWD system.

And apparently, there is a lot of misunderstanding about how this system works. I doubt that my F150 is broken nor an outlier in how it works in 4A.

Just FYI…from reading the internet, if we do indeed have BorgWarner 4417 TC, then it is an old as heck design!

4417 came our around 2007. It is pretty much the same as the 4416, but includes a default off-road program. 4416 came out in 2003.

So, basically, it is a 20+ year old TC design!

Before we crap on Dodge……but the newer Ram uses BW 48-11, which came out in 2019. So unless BW has tradition of making their TC worst over the years, Dodge Ram TC is probably just as good, but likely better than our 4417.
This design is probably the easiest way to put an AWD-like system into an existing TC. It's not a great AWD system, but it's not the worst either. The only thing one really has to remember with this system is that because a clutch pack replaces the pawls used to lock the driveshafts together, that clutch pack is what allows the system to tolerate some slip between front and rear driveshaft speeds. When a lot of pressure is applied to that pack, it locks the driveshafts together, thus allowing 4H and 4L as otherwise selected. So, when in 4A, the more pressure is applied to the clutch pack (and therefore the more torque is sent to the front driveshaft) the more the TC is going to act like a typical 4WD TC and it's going to tolerate slip between driveshafts less and less.

End result with this design, don't give it all the beans while trying to make sharp corners. The TC will hate it and something may break.
Reply
Old Jun 20, 2024 | 11:34 AM
  #43  
tigmd99's Avatar
Thread Starter
Senior Member
Liked
Loved
Community Favorite
 
Joined: Apr 2023
Posts: 331
Likes: 232
Default

Thanks to the torrential rain in my city, i got to test out the 4A mode more. Quick summary: VERY IMPRESSIVE.

1. On wet highway road and no slip, it is RWD/2wd even when i prod the gas pedal.

2. BUT, as soon as i hit a water puddle on the highway at about 75 mph, i can see the front axle lit up with power almost instantly. And it keeps sending power to the front axle for several seconds after i pass the puddle.

NOTE: I did NOT feel any slippage going over the puddle NOR do i see any stability control light lit up either.

3. Another time, the road was quite soak, and i suddenly saw power going to the front axle for several seconds and then back to RWD.

3a. I tried to swerve back and forth on wet road to see if i can get the AWD to turn on…nope. RWD/2WD. So yeah, it only sends power to the front axle when there is slippage.

Again, neither of these two circumstances (when AWD turn ON) had any stability control light come on nor did i feel instability. Both times at highway speed.

So, yeah, the 4A mode is quite sensitive and comes on instantly. Basically it seems to send power to the front axle even before i realize anything was wrong. Very nice.

Last edited by tigmd99; Jun 20, 2024 at 11:37 AM.
Reply
Old Jun 20, 2024 | 12:33 PM
  #44  
Sherman-GT350's Avatar
Senior Member
Liked
Loved
Community Favorite
 
Joined: Dec 2023
Posts: 914
Likes: 574
Default

Originally Posted by tigmd99
I disagree. At any speed, having power going to BOTH axles is of benefit to traction. If slippage occurs, it is always nice to have traction at both axles already active. Stability control can only do so much to correct. Stability control will (REACTIVELY) brake the slipping wheel (AFTER SLIP has occurred) and throttle down the engine. Having power to both ends of the car is better for stability in that split instance.

And having power to BOTH axles BEFORE, DURING, and AFTER slippage is SIGNIFICANTLY better for stability than having the car SUDDENLY shifting power to the front axle a few milliseconds AFTER slipping/sliding occurring. And then after traction is regained, power again suddenly stops going to the front axle.

This is why on-demand AWD is not a thing in high speed racing nor auto crossing.
Its also why AWD cars are generally slower around tracks than FWD/RWD cars.. but anyways. You've made up your mind, so no facts will change it.
Reply




All times are GMT -4. The time now is 01:46 PM.