T-Case Problem
Thread Starter
|
Senior User
Joined: Dec 2004
Posts: 439
Likes: 0
From: North Of Pittsburgh
T-Case Problem
How much damage can be caused if the T-case is worn so badly that it is sending power to the front axel all the time. It is a 98' Explorer 4.0 SOHC. Notice it most when coming to a stop and pulling out. Do I need to have this fixed A.S.A.P or can it wait.
Thanks For All The Help
Thanks For All The Help
Senior User
Joined: Jul 2004
Posts: 475
Likes: 0
From: Winnipeg, Mb. Canada
Well, if it's a 4x4 and NOT AWD, then you'll toast it soon than later. Get it looked at ASAP! Driving on dry pavement in 4x4 is certain t-case death. Are you sure that it's "worn"? Could be the shift motor is just stuck. If you do a search in this forum, you'll find a link for fixing/cleaning the shift motor.
Good luck.
Good luck.
Thread Starter
|
Senior User
Joined: Dec 2004
Posts: 439
Likes: 0
From: North Of Pittsburgh
Well if I disconect the power from the T-case nothing changes and it sounds like it is shifting. According to Borg Warner the case is designed to be driven on any dry surface without damage but I am not sure about the axel. I will however have a new t-case installed shortly as soon as I can find one. Here in pa they are somewhat hard to come by.
Thread Starter
|
Senior User
Joined: Dec 2004
Posts: 439
Likes: 0
From: North Of Pittsburgh
As soon as I get home I will post the VIN number as the tag is missing from the case. Thanks alot. I also called f650pickups.com and got some really good info on the trucks that they build and alot of part numbers from them. Thanks again
Thread Starter
|
Senior User
Joined: Dec 2004
Posts: 439
Likes: 0
From: North Of Pittsburgh
Posting Guru
Joined: Mar 2002
Posts: 1,942
Likes: 3
From: Willamette Valley, Oregon
Does the Explorer emblem on the hatch say all wheel drive? What are the selections on the switch on the dash? I would not drive this on dry pavement until it is out of four wheel drive because you could cause more damage.
One of the things that could have happened is the viscous clutch in the t-case could have gone bad causing you to be in four wheel drive all the time.
Another that was suggested is that the shift fork could have gotten bent and is stuck in 4-high.
Another and common for the non-AWD is the electric shift motor could be stuck in 4-high and just needs to be cleaned and there is a write up on this site for that.
One of the things that could have happened is the viscous clutch in the t-case could have gone bad causing you to be in four wheel drive all the time.
Another that was suggested is that the shift fork could have gotten bent and is stuck in 4-high.
Another and common for the non-AWD is the electric shift motor could be stuck in 4-high and just needs to be cleaned and there is a write up on this site for that.
Trending Topics
Thread Starter
|
Senior User
Joined: Dec 2004
Posts: 439
Likes: 0
From: North Of Pittsburgh
The shift motor works I can shoft from hi to low and it is a control trac not awd. I have been told of the clutches going bad many of times but I never thought that when they went bad that the axel would get power all the time. So I guess the t-case needed to be replaced long ago. I was thinking of just buying a new one as the cost of having it rebuilt will cost almost $2,000.00 and that was the lowest bid that I could find.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
10 Most Surprising 2026 Ford Truck Features!
Joe Kucinski
Top 10 Ford Trucks Coming to Mecum Indy 2026
Brett Foote
5 Best / 5 Worst Ford Truck Wheels of All Time
Joe Kucinski
Ford Super Duty: 5 Things Owners LOVE, 5 Things They LOATHE!
Joe Kucinski
Every 2026 Ford Truck Engine RANKED from WORST to FIRST!
Michael S. Palmer
The Best F-150 Deal of Every Trim Level (XL through Raptor)
Joe Kucinski
Posting Guru
Joined: Mar 2002
Posts: 1,942
Likes: 3
From: Willamette Valley, Oregon
A control trac is an AWD! It send 35% of the power to the front at all times. If you are having troubles with the t-case when corning and low speeds, it could just be a problem with metal particles on the two sensors that are on the t-case.
Posting Guru
Joined: Mar 2002
Posts: 1,942
Likes: 3
From: Willamette Valley, Oregon
The all-wheel drive transfer case is a two-piece aluminum, chain driven, viscous clutch type unit. This produces a system in which all-wheel drive is always activated. The all-wheel drive transfer case is automatic and has no external controls.
The viscous clutch is a torque distribution device. It is non-repairable. The internal construction of the viscous clutch consists of alternating plates that are connected to the front and rear outputs of the transfer case. The viscous clutch is filled with a high viscosity fluid which flows through slots in the plates. The resistance to shear causes the plates to transmit torque at the needed ratio. The ratio that torque is transmitted at is approximately 35% front and 65% rear.
A front differential compensates for the difference between the inner and outer wheels. However, when one driveline component travels farther than another, there will be driveline or torsional windup that must be released.
Torque is transmitted through the input shaft to the planet carrier assembly. Torque flow continues through the gear ring to the rear output shaft. Torque also flows from the planet carrier assembly to the sun gear shaft, which is splined to the drive sprocket. The drive gear is connected to the driven sprocket by the drive chain. Torque continues through the driven sprocket to the front output shaft flange. The viscous clutch provides the connection between the gear ring and the sun gear shaft.
The A4WD system is an electronic shift 4x4 system that allows the operator to choose between three different 4x4 modes. The operator can switch between A4WD and 4WD HIGH modes at any speed. To engage or disengage LOW range, the vehicle speed must be less than 5 km/h, the brake depressed, and the transmission must be in NEUTRAL.
The front/rear driveshaft speed sensors (Hall effect) are mounted to the transfer case and detect the speed of the front and rear driveshafts. This input is used by the generic electronic module (GEM) primarily to control A4WD operation.
The throttle position output signal is provided to the GEM from the powertrain control module (PCM). This signal is used by the GEM in controlling the A4WD clutch.
The shift motor sense plate, an integral part of the electric shift motor, informs the GEM to the position of the transfer case.
The digital TR sensors are located on the LH side of the transmission; these sensors inform the GEM when the transmission is in the neutral position.
The electric shift motor is mounted externally at the rear of the transfer case. It drives a rotary cam which moves the mode fork and range fork within the transfer case between the A4WD, 4HIGH, and LOW range positions.
The 4x4 shift motor uses a module containing two relays which, under the control of the GEM, shifts the transfer case shift motor between A4WD, 4HIGH, and 4LOW modes.
The solid state clutch relay is used to activate the A4WD clutch within the transfer case.
System Function
Hall effect sensor monitors input and output shaft speed.
In the A4WD (C-Trac) system, the GEM varies the torque sent to the front driveline by controlling the transfer case clutch. At rest and under cruising conditions, the GEM activates the transfer case clutch a minimum duty cycle (percentage of time the clutch is turned on), which allows for the slight difference between the front and rear driveshafts which normally occurs when negotiating a corner on dry pavement. Under any of the following conditions, the GEM will increase the duty cycle in order to prevent or control slip:
l Slip is detected (by using the Hall Effect Sensors)
l Heavy acceleration.
l Very light or zero throttle at speeds above 25 km/h (40 mph)
Feature inputs:
l 4WD mode switch.
l Digital TR sensor.
l Vehicle speed signal (transmitted from the ABS module).
l Front/rear driveshaft speed sensors.
l Throttle position information from the PCM.
l Contact plate position inputs A, B, C, D.
Feature outputs:
l Solid state clutch relay (pulse width modulated signal: grounded when relay is on, battery potential when relay is off).
l A4WD indicator (ground when activated, open circuit when deactivated).
Shifts between A4WD and 4x4 HIGH can be made at any speed. Listed below are the inputs and outputs needed by the GEM to execute a change between any of these modes.
Feature inputs:
l 4WD mode switch.
l Hall effect sensors.
l Contact plate position inputs A, B, C, D.
Feature outputs:
l 4x4 shift motor relay outputs.
l Solid state clutch relay (pulse width modulated signal; grounded when relay is on, battery potential when relay is off).
l 4x4 HIGH cluster indicator (ground when activated, open circuit when deactivated).
When shifting into or out of LOW range, the GEM requires that the vehicle speed is less than 5 km/h (3 mph), the brake is applied, and the transmission is in NEUTRAL.
Feature inputs:
l 4WD mode switch.
l Contact plate position inputs A, B, C, D.
l Vehicle speed signal (transmitted from ABS module).
l Brake input (battery voltage when brake is depressed, open circuit when not activated).
l Digital TR sensor (ground when transmission is in NEUTRAL, open circuit otherwise).
l Start/clutch depressed input.
Feature outputs:
l 4x4 shift motor relay outputs.
l Cluster indicators (ground when activated, open circuit when deactivated).
l Solid state clutch relay (pulse width modulated signal; grounded when relay is on, battery potential when relay is off).
The viscous clutch is a torque distribution device. It is non-repairable. The internal construction of the viscous clutch consists of alternating plates that are connected to the front and rear outputs of the transfer case. The viscous clutch is filled with a high viscosity fluid which flows through slots in the plates. The resistance to shear causes the plates to transmit torque at the needed ratio. The ratio that torque is transmitted at is approximately 35% front and 65% rear.
A front differential compensates for the difference between the inner and outer wheels. However, when one driveline component travels farther than another, there will be driveline or torsional windup that must be released.
Torque is transmitted through the input shaft to the planet carrier assembly. Torque flow continues through the gear ring to the rear output shaft. Torque also flows from the planet carrier assembly to the sun gear shaft, which is splined to the drive sprocket. The drive gear is connected to the driven sprocket by the drive chain. Torque continues through the driven sprocket to the front output shaft flange. The viscous clutch provides the connection between the gear ring and the sun gear shaft.
The A4WD system is an electronic shift 4x4 system that allows the operator to choose between three different 4x4 modes. The operator can switch between A4WD and 4WD HIGH modes at any speed. To engage or disengage LOW range, the vehicle speed must be less than 5 km/h, the brake depressed, and the transmission must be in NEUTRAL.
The front/rear driveshaft speed sensors (Hall effect) are mounted to the transfer case and detect the speed of the front and rear driveshafts. This input is used by the generic electronic module (GEM) primarily to control A4WD operation.
The throttle position output signal is provided to the GEM from the powertrain control module (PCM). This signal is used by the GEM in controlling the A4WD clutch.
The shift motor sense plate, an integral part of the electric shift motor, informs the GEM to the position of the transfer case.
The digital TR sensors are located on the LH side of the transmission; these sensors inform the GEM when the transmission is in the neutral position.
The electric shift motor is mounted externally at the rear of the transfer case. It drives a rotary cam which moves the mode fork and range fork within the transfer case between the A4WD, 4HIGH, and LOW range positions.
The 4x4 shift motor uses a module containing two relays which, under the control of the GEM, shifts the transfer case shift motor between A4WD, 4HIGH, and 4LOW modes.
The solid state clutch relay is used to activate the A4WD clutch within the transfer case.
System Function
Hall effect sensor monitors input and output shaft speed.
In the A4WD (C-Trac) system, the GEM varies the torque sent to the front driveline by controlling the transfer case clutch. At rest and under cruising conditions, the GEM activates the transfer case clutch a minimum duty cycle (percentage of time the clutch is turned on), which allows for the slight difference between the front and rear driveshafts which normally occurs when negotiating a corner on dry pavement. Under any of the following conditions, the GEM will increase the duty cycle in order to prevent or control slip:
l Slip is detected (by using the Hall Effect Sensors)
l Heavy acceleration.
l Very light or zero throttle at speeds above 25 km/h (40 mph)
Feature inputs:
l 4WD mode switch.
l Digital TR sensor.
l Vehicle speed signal (transmitted from the ABS module).
l Front/rear driveshaft speed sensors.
l Throttle position information from the PCM.
l Contact plate position inputs A, B, C, D.
Feature outputs:
l Solid state clutch relay (pulse width modulated signal: grounded when relay is on, battery potential when relay is off).
l A4WD indicator (ground when activated, open circuit when deactivated).
Shifts between A4WD and 4x4 HIGH can be made at any speed. Listed below are the inputs and outputs needed by the GEM to execute a change between any of these modes.
Feature inputs:
l 4WD mode switch.
l Hall effect sensors.
l Contact plate position inputs A, B, C, D.
Feature outputs:
l 4x4 shift motor relay outputs.
l Solid state clutch relay (pulse width modulated signal; grounded when relay is on, battery potential when relay is off).
l 4x4 HIGH cluster indicator (ground when activated, open circuit when deactivated).
When shifting into or out of LOW range, the GEM requires that the vehicle speed is less than 5 km/h (3 mph), the brake is applied, and the transmission is in NEUTRAL.
Feature inputs:
l 4WD mode switch.
l Contact plate position inputs A, B, C, D.
l Vehicle speed signal (transmitted from ABS module).
l Brake input (battery voltage when brake is depressed, open circuit when not activated).
l Digital TR sensor (ground when transmission is in NEUTRAL, open circuit otherwise).
l Start/clutch depressed input.
Feature outputs:
l 4x4 shift motor relay outputs.
l Cluster indicators (ground when activated, open circuit when deactivated).
l Solid state clutch relay (pulse width modulated signal; grounded when relay is on, battery potential when relay is off).
Former Vendor
Joined: Jan 2006
Posts: 3,849
Likes: 1
From: Seattle
F87A-7A195-CA NEW, LIST $1788.22 FTE $1609.31 SPECIAL $1500.00 PLUS SHIPPING
COMES OUT OF DETROIT SO A FEW DAYS FOR ME TO GET.
<br>
by the way it is a elec shift Warner 4405 and not a viscous drive!
<br>
Please visit my web page.
<br>
Thanks Ed
COMES OUT OF DETROIT SO A FEW DAYS FOR ME TO GET.
<br>
by the way it is a elec shift Warner 4405 and not a viscous drive!
<br>
Please visit my web page.
<br>
Thanks Ed
Thread Starter
|
Senior User
Joined: Dec 2004
Posts: 439
Likes: 0
From: North Of Pittsburgh
IF I have confused anyone I am sorry. I have The A4WD System and in my owners manual they call it Control Trac System. Again I am very sorry for any confusion that this may have caused.
Thread
Thread Starter
Forum
Replies
Last Post
454wizbang
1987 - 1996 F150 & Larger F-Series Trucks
4
Jan 23, 2016 05:19 PM
OpieCunningham
1973 - 1979 F-100 & Larger F-Series Trucks
23
Oct 25, 2009 11:10 PM
Goodold71
Clutch, Transmission, Differential, Axle & Transfer Case
10
Mar 1, 2004 01:09 AM
