How does the vacuum lock work?
The vacuum pulse is sent to the hub for about 15 seconds then stops. In that time the hubs should click in and be locked. When you turn the 4wd off it sends a shorter and less powerful vacuum pulse to the hubs and clicks them again to unlock them.
How does the hub lock work?
The hubs work on a pulse not a constant vacuum. The easiest way to describe it is like a clicker ink pen. The vacuum pulse is sent to the hub for about 15 seconds then stops. In that time the hubs should click in and be locked.
Why does the hub stay locked after vacuum pulse?
The hub will stay locked after the vacuum pulse. To go back to 2wd, a “low” vacuum pulse is put on the hub (for 10 seconds) and released. This low vacuum pulse is supposed to partially compress the cylinder and release it, causing it to latch on itself, becoming physically short, so it does not push on the ring gear and the hub disengages.
How does a high level vacuum work?
Something do do with a low level vacuum and a high level vacuum operates the hubs to get them to and from the locked state. I do know know about 4 and 5. The hubs work on a pulse not a constant vacuum. The easiest way to describe it is like a clicker ink pen. The vacuum pulse is sent to the hub for about 15 seconds then stops.
What happens when you turn off 4WD?
How long does it take for a vacuum pump to cut off?
How do hubs work?
Why does my ESOF have vacuum leaks?
What does a high level vacuum do?
What does it mean when a pump is running constantly?
Does Soleniod switch back?
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How do vacuum hubs work?
For this design, the vacuum is placed on the system unlocking the hubs while the truck runs in 2-wheel drive mode. When shifting to 4-wheel drive, vacuum is released, which locks the hubs. This leaves the front axle locked for fail-safe operation.
How do Auto locking hubs work?
Automatic Locking Hubs Automatic hubs work on the same principle as freewheeling hubs without the need to exit the car to manually turn the actuator. Many newer 4WD's come with this as standard equipment. Very simply these units self-engage 'on the fly' when 4WD is selected within the cab.
Which way to turn locking hubs?
For proper operation, make sure that each hub is fully engaged and that both hub locks are set to the same position (both set to LOCK or both set to AUTO). To engage LOCK, turn the hub locks completely clockwise; to engage AUTO, turn the hub locks completely counterclockwise.
Is it OK to leave hubs locked?
The rule of thumb is to leave hubs unlocked in the summer time and locked in the winter time. Having the hubs locks will cost in fuel economy. With hubs locked the front differential is engaged and spinning when the wheels are in motion causing drag.
Can you keep your hubs locked in 2WD?
0:592:17Manual Hubs to lock or not to lock while in 2wd - YouTubeYouTubeStart of suggested clipEnd of suggested clipIt won't damage your car at all it will cost you a bit more fuel.MoreIt won't damage your car at all it will cost you a bit more fuel.
Should hubs be locked or free?
I would recommend you leave your hubs locked while in 2WD during bad weather seasons. This will allow you to shift in and out of 4WD whenever the need arises. Good news is that you will not need to stop for shifting into 4WD - with the locking hubs engaged the drive lines are synchronized.
Why do people lock their hubs?
This is done to reduce the mechanical resistance of the front-portion of the drivetrain when four-wheel drive is not in use.
Why are manual locking hubs better?
Axles, differentials, and driveshafts still turn, even in 2WD, which adds extra wear and tear on a vehicle and decreases fuel economy. When you switch to a manual WARN 4WD Hub, you have the ability to disconnect front wheels from the front drivetrain, increasing fuel economy, and decreasing drivetrain wear.
Do front wheel hubs lock automatically?
Typically, locking hubs work to engage and disengage the front wheels from the front shafts. While modern vehicles are fitted with auto-locking hubs, older 4WD vehicles use manual locking hubs.
Will manual locking hubs improve MPG?
I'd say it is best to use manual locking hubs in conjunction with some good narrow tires to see an improvement worth mentioning. I have seen as much as nearly 20 MPG for a tank before with my current set up.
Should you lock your hubs in snow?
I would recommend you leave your hubs locked while in 2WD during bad weather seasons. This will allow you to shift in and out of 4WD whenever the need arises.
What does locking the hubs do on a 4WD?
What are Manual Locking Hubs? Manual hubs are a type of part used to disconnect a wheel from an axle in a four-wheel drive system. This allows the wheels to rotate without having the front driveline turn. This saves wear and tear on the vehicle and also helps improve fuel economy.
Hubs Not Holding Vacuum | Ford Powerstroke Diesel Forum
2004 F350 Lariat, EC, SRW, 6.0 TD, LOADED Shorty SCT SF3, MBRP Turbo Back 409, Coolant Filter Oil Bypass Filter, Fumoto Valve, HFCM Drain Plug A/C Control Valve, 50 gal TransferFlow
vacuum leak to hubs | Ford Powerstroke Diesel Forum
I hve a 2006 6.0 diesel with a vacuum leak somewhere between the vacuum canister and the hubs, and, as I almost never use 4x4, can I just block off the line going down to the hubs until I have time and money to fix it? if so, what position would I leave the hubs in? anything else to consider...
Is vacuum line still necessary with manual locking hubs on an F350?
Several years ago, on my gas engine 2003 F350, I replaced my auto locking hubs with Warn manual hubs. Recently I am experiencing the dreaded A/C defaulting to the defrost vents under low vacuum conditions due to a vacuum leak.
Ford Superduty 4wd hubs problem QUICK FIX (ESOF)
Superduty "4x4 not engaging" problems? This is a very common issue, here is how to fix it. It might be a quick patch/replacement of a vacuum line, or a solenoid replacement. I made a quick video that will only take a couple minutes for you to figure out what the problem is, and depending on the problem, the actual fix shouldn't take you more than 15 minutes.
What happens when you turn off 4WD?
When you turn the 4wd off it sends a shorter and less powerful vacuum pulse to the hubs and clicks them again to unlock them. If your hubs don't turn from from auto to locked you will need to take them off and clean and lube them. Pull them off and soak them in trans mission fluid overnight.
How long does it take for a vacuum pump to cut off?
Start by checking the vacuum lines at the hubs. They turn "crunchy" very quickly there. It should take no more than 2 minutes for the vacuum pump to cut off from an empty tank. ESOF 4WD Troubleshooting. It is easier to troubleshoot the system if you have a “Mityvac” vacuum pump.
How do hubs work?
The hubs work on a pulse not a constant vacuum. The easiest way to describe it is like a clicker ink pen. The vacuum pulse is sent to the hub for about 15 seconds then stops. In that time the hubs should click in and be locked.
Why does my ESOF have vacuum leaks?
Most likely culprit is the vacuum lines leading to the front axle. These tend to split very easily and cause 99% of the vacuum leaks you see with the ESOF setup.
What does a high level vacuum do?
That seems to be normal operation. Something do do with a low level vacuum and a high level vacuum operates the hubs to get them to and from the locked state.
What does it mean when a pump is running constantly?
If the pump is running constantly you either have a leak or the pump is bad. Mine was and once replaced it made a huge difference.
Does Soleniod switch back?
The switching soleniod it seems as though it is duty cycled it sends vacuum to hubs for a certain amount of time and then switches back, or once it sees a certain amount of vacuum it then switches back.
How to engage a vacuum hub?
The vacuum operation (or at least whatever vacuum operation you still have) will still work, but you can now use your finger to engage and disengage the hub manually. To engage the hub, push the cylinder in fully and release. You will feel the cylinder unlatch and fully push back out toward you and the hub will now be locked.
How to go back to 2WD?
To go back to 2wd, a “low” vacuum pulse is put on the hub (for 10 seconds) and released. This low vacuum pulse is supposed to partially compress the cylinder and release it, causing it to latch on itself, becoming physically short, so it does not push on the ring gear and the hub disengages.
How many miles does a 98 Ranger 4x4 have?
I have a 98 Ranger 4×4 with 105k miles. For most of us, this means two things- It’s been a great truck, and the vacuum hubs are junk. Mine actually worked fairly well until recently, but lately I never know if they lock or unlock properly. The other day I tried to go back to 2wd and could tell something was amiss, and when I got home and jacked it up, one hub had unlocked and the other one was still locked. I decided once and for all to figure this thing out and fix it.
What does a cylinder do?
The cylinder thing is kind of like a push-button ballpoint pen. This is the key to understanding the hubs. When you fully compress the cylinder on itself and release it, it will “come apart” which makes it physically long so it pushes on the hub ring gear and therefore engages the hub. When you now push the cylinder together about half way and release it, it will latch on itself becoming locked together and much shorter. When it is short like this, it will not push on the ring gear, so the hub is disengaged.
How to change a wheel hub cover?
The hub cover modification is very easy. Take a pair of dikes and cut out the piece of plastic in the middle that looks like a wagon wheel. Then using your fingers, push out the round piece of screen. This puts a finger-sized hole in the hub cover.
What happens when a hub is disengaged?
The cover will pull out, a rubber cover will come out, and the cylinder thing will fall out. If your hub is disengaged, the cylinder will be “together” and if your hub is engaged, the cylinder will be in 3 pieces- two white pieces and a spring in the middle.
How long does it take for a Ford 4WD to unlock the hub?
Ford decided to use vacuum to do this. So when 4wd is selected, a long, full vacuum pulse (45 seconds according to my factory service manual) is put on the hub and released.
How to go back to 2WD?
To go back to 2wd, a "low" vacuum pulse is put on the hub (for 10 seconds) and released. This low vacuum pulse is supposed to partially compress the cylinder and release it, causing it to latch on itself, becoming physically short, so it does not push on the ring gear and the hub disengages. Once again, only a pulse of low vacuum is needed, once it’s in 2wd, it will stay there.
How many miles does a 98 Ranger 4x4 have?
I have a 98 Ranger 4×4 with 105k miles. For most of us, this means two things- It’s been a great truck, and the vacuum hubs are junk. Mine actually worked fairly well until recently, but lately I never know if they lock or unlock properly. The other day I tried to go back to 2wd and could tell something was amiss, and when I got home and jacked it up, one hub had unlocked and the other one was still locked. I decided once and for all to figure this thing out and fix it.
What does a cylinder do?
The cylinder thing is kind of like a push-button ballpoint pen. This is the key to understanding the hubs. When you fully compress the cylinder on itself and release it, it will "come apart" which makes it physically long so it pushes on the hub ring gear and therefore engages the hub. When you now push the cylinder together about half way and release it, it will latch on itself becoming locked together and much shorter. When it is short like this, it will not push on the ring gear, so the hub is disengaged.
How does a hub work?
The hub is engaged when the "ring gear" in the hub is pushed in and held in. The ring gear has a big spring beneath it that pushes it out to keep the hub disengaged. The white two-piece "cylinder thing" is what either holds the ring gear in (thus locking the hub) or allows the ring gear to push itself out (thus unlocking the hub).
How to know if your hub is unlocked?
If you press it back together about halfway until you feel a click, then release it, it will lock back on itself, becoming short, so it won’t push on the ring gear, so the hub is unlocked.
What does it feel like when a hub is engaged?
When the hub in engaged, you will feel the cylinder pushing out very hard, when disengaged, you will feel that the cylinder is not pushing our very hard and actually has some "play" in it.
How to unlock a cover on a sandbox?
Put the needle nose pliers in a set of slots and turn counter-clockwise about a quarter inch to unlock the cover.
How to tell if hubs are partially released?
If vacuum drops to or below 5 inches, the hubs may be partially released or applied. An intermittent issue is best diagnosed with a vacuum gauge teed into the IWE control system. Drive the vehicle while observing the vacuum gauge versus the grinding/whining issue. Also, verify that the vacuum coming to the IWE reservoir is correct and consistent. On gas engines, it is supplied by the engine manifold. It is typical to see anywhere from 16 to 22 inches of vacuum at idle. Diesel applications should record a similar range from the vacuum pump.
How to check IWE solenoid?
With no voltage applied, the vacuum switch is closed, which blocks vacuum from the control port. You can use jumper wires from the vehicle’s battery or an external power source. Applying a 12-volt source opens the switch, allowing vacuum to the control port. No voltage applied means no vacuum at the control port. Use a DVOM to verify the vehicle is giving the proper signal by back probing the control circuit in 2WD mode with the engine running.
How to check IWE actuators?
Remove the switched vacuum line that goes to the IWE actuators and install your vacuum pump. Pump and hold the vacuum and wait for 60 seconds (1 minute). Verify that the IWE actuators release (unlocked). Observe your vacuum gauge reading from start to finish. If your reading drops by 1 inch or less after 60 seconds, the system checks good through all of the hoses and both actuators. Note if either IWE actuator does not move, there could be a blockage in the vacuum line (s) or a frozen or damaged IWE actuator.
What is an IWE valve?
The system’s check valves are designed to maintain the highest vacuum level in the reservoir and control system to maintain commanded operation. The IWE solenoid controls the vacuum signal based on the selection of 2WD or 4WD. In 2WD mode, the solenoid is energized, providing vacuum to the IWE actuators. When 4WD is selected, the IWE solenoid is de-energized, which causes vacuum to be evacuated, allowing the IWE actuators to lock.
Why does my IWE hub make a whining noise?
If you hear grinding or whining noises from one or both front hubs at certain speeds or loads in 2WD mode, you probably have a leak in your IWE vacuum system. On vehicles equipped with the TOD system, grinding or whining may occur after heavy acceleration or after an ABS-induced 4WD command. A quick check is to remove and plug the vacuum feed into the IWE actuators and retest. If the grinding/whining noises go away, then unplug and reconnect the hoses and continue diagnosing the system.
How does IWE work?
Ford’s IWE system works off of engine vacuum. Diesel applications are equipped with a vacuum pump for the brake booster reservoir and also serves the IWE system. It consists of IWE actuators (one in each front hub), a vacuum storage reservoir, vacuum lines, one-way check valves, and an actuator control solenoid (figure 1). The IWE actuators are also referred to as Constant Vacuum Hub lock (CVH) actuators. This design was first introduced in 2004 applications and worked opposite of the earlier Ford design CVH actuators. For this design, the vacuum is placed on the system unlocking the hubs while the truck runs in 2-wheel drive mode. When shifting to 4-wheel drive, vacuum is released, which locks the hubs. This leaves the front axle locked for fail-safe operation. Note that if the front axle remains locked, it will not cause driveability or durability issues. However, it’ll decrease fuel mileage due to the additional rotating parts.
What is IWE on a Ford truck?
While all of these systems offer their pros, they also have their cons. In their latest venture, Ford has struck their version of the best of all worlds as they see it with the introduction of the Integrated Wheel End (IWE) actuator system. The IWE actuators are a part of the Electronic Shift-On-The-Fly (ESOF) and Torque-On-Demand (TOD) systems which control the entire 4-wheel drive operation. We will look at the IWE system for controlling on-demand power flow to the front axle on Ford medium to heavy-duty trucks.
What happens when you turn off 4WD?
When you turn the 4wd off it sends a shorter and less powerful vacuum pulse to the hubs and clicks them again to unlock them. If your hubs don't turn from from auto to locked you will need to take them off and clean and lube them. Pull them off and soak them in trans mission fluid overnight.
How long does it take for a vacuum pump to cut off?
Start by checking the vacuum lines at the hubs. They turn "crunchy" very quickly there. It should take no more than 2 minutes for the vacuum pump to cut off from an empty tank. ESOF 4WD Troubleshooting. It is easier to troubleshoot the system if you have a “Mityvac” vacuum pump.
How do hubs work?
The hubs work on a pulse not a constant vacuum. The easiest way to describe it is like a clicker ink pen. The vacuum pulse is sent to the hub for about 15 seconds then stops. In that time the hubs should click in and be locked.
Why does my ESOF have vacuum leaks?
Most likely culprit is the vacuum lines leading to the front axle. These tend to split very easily and cause 99% of the vacuum leaks you see with the ESOF setup.
What does a high level vacuum do?
That seems to be normal operation. Something do do with a low level vacuum and a high level vacuum operates the hubs to get them to and from the locked state.
What does it mean when a pump is running constantly?
If the pump is running constantly you either have a leak or the pump is bad. Mine was and once replaced it made a huge difference.
Does Soleniod switch back?
The switching soleniod it seems as though it is duty cycled it sends vacuum to hubs for a certain amount of time and then switches back, or once it sees a certain amount of vacuum it then switches back.