TC with diffs locked
#1
06-23-2013, 12:47 AM
#2
06-23-2013, 02:22 AM
Recovery Vehicle
#3
06-23-2013, 08:25 AM
#5
06-23-2013, 01:20 PM
And if you have added CDL to your 99 thu 01, you can turn off the TC ny leaving the CDL on, turn off the engine and then restart the engine, now you have shut off the TC, ABS and Hill Decent.
Any time you can run with out TC, you are saving your brake pads fron a lot of wear and heat.
Any time you can run with out TC, you are saving your brake pads fron a lot of wear and heat.
I just recently found out that the DII also has an electronic brake distribution system that adjusts brake bias by way of the ABS system. With the ABS disabled, this feature is inop and the rear brakes receive full pressure which can result in premature lockup of the rear wheels and loss of control if you're not expecting it.
Just something to know if you're going to be driving around without functioning ABS.
#8
06-23-2013, 05:41 PM
Bias proportioning was formerly handled by a mechanical proportioning valve that fed the rear brakes on the RRC's and the DI, it was replaced with the EBD function of the ABS with the introduction of the DII. If you allow the same pressure to the rear wheels that you do to the front wheels, you run the risk of the rears locking up before the fronts under some conditions. If you're not expecting it, you're going to have a bad time.
On where it's discussed:
Page 70-20 of the RAVE Manual
EBD
The EBD function optimises the distribution of hydraulic pressure between the front and rear axles, under all vehicle
load configurations and road conditions, to maintain vehicle stability during braking. EBD operates in forward and
reverse and is automatically enabled whenever the ABS modulator is in the normal braking mode at vehicle
deceleration rates of 0.3 g and above (i.e. medium to high brake pedal loads). EBD operation is similar to that of ABS,
but is calibrated to intervene at lower wheel slip limits and operates the brakes in axle pairs instead of individually.
During braking, if the SLABS ECU detects the wheels of one axle going slower than those of the other axle, i.e. a
potential wheel slip situation, it signals the ABS modulator to close the inlet solenoid valve for the brakes of the slower
wheels. This prevents any further increase in hydraulic pressure to those brakes, while allowing the hydraulic pressure
to the brakes on the other axle to increase and so maximise the overall braking effort. If the wheel speeds of the axle
being subjected to EBD control return within the calibrated wheel slip limits, the SLABS ECU signals a stepped
opening of the inlet solenoid valves, which allows a progressive increase of hydraulic pressure to the related brakes.
Operation of EBD is detectable from a stiffening of brake pedal movement as the inlet solenoid valves close and a
slight pulsing of the brake pedal as the inlet solenoid valves open. EBD operation ceases immediately the brake pedal
is released.
The wheel slip limit for EBD operation varies with vehicle speed. During normal operation, the inlet solenoid valves
always operate in axle pairs, with only one axle pair closed at any one time. Since the most lightly loaded wheel during
a braking manoeuvre will usually be the first to reach the slip limit, under most vehicle load configurations and road
conditions EBD control occurs on the trailing axle. However, EBD control can occur on the leading axle or switch
between axles during the braking manoeuvre.
The EBD function optimises the distribution of hydraulic pressure between the front and rear axles, under all vehicle
load configurations and road conditions, to maintain vehicle stability during braking. EBD operates in forward and
reverse and is automatically enabled whenever the ABS modulator is in the normal braking mode at vehicle
deceleration rates of 0.3 g and above (i.e. medium to high brake pedal loads). EBD operation is similar to that of ABS,
but is calibrated to intervene at lower wheel slip limits and operates the brakes in axle pairs instead of individually.
During braking, if the SLABS ECU detects the wheels of one axle going slower than those of the other axle, i.e. a
potential wheel slip situation, it signals the ABS modulator to close the inlet solenoid valve for the brakes of the slower
wheels. This prevents any further increase in hydraulic pressure to those brakes, while allowing the hydraulic pressure
to the brakes on the other axle to increase and so maximise the overall braking effort. If the wheel speeds of the axle
being subjected to EBD control return within the calibrated wheel slip limits, the SLABS ECU signals a stepped
opening of the inlet solenoid valves, which allows a progressive increase of hydraulic pressure to the related brakes.
Operation of EBD is detectable from a stiffening of brake pedal movement as the inlet solenoid valves close and a
slight pulsing of the brake pedal as the inlet solenoid valves open. EBD operation ceases immediately the brake pedal
is released.
The wheel slip limit for EBD operation varies with vehicle speed. During normal operation, the inlet solenoid valves
always operate in axle pairs, with only one axle pair closed at any one time. Since the most lightly loaded wheel during
a braking manoeuvre will usually be the first to reach the slip limit, under most vehicle load configurations and road
conditions EBD control occurs on the trailing axle. However, EBD control can occur on the leading axle or switch
between axles during the braking manoeuvre.
#9
06-23-2013, 09:54 PM
Administrator
Join Date: Apr 2006
Location: Denver, Colorado
Posts: 25,707
Likes: 0
Received 103 Likes
on
85 Posts
11 years of wheeling with the ABS has never cause a problem and I have always had front an rear brakes. I based my original concern based on your statement," this feature is inop and the rear brakes receive full pressure which can result in premature lockup of the rear wheels and loss of control if you're not expecting it."
Even on snow, mud or sand, never had any issues.
Even on snow, mud or sand, never had any issues.
#10
06-23-2013, 10:34 PM