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2002 G500
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Discussion Starter #1
Please pardon me if my wording on this stuff is wrong. My differential locks wont disengage. My middle locker is engaged and the front locker are engaged and my rear lockers are not engaged. I didnt even think this was possible. I thought they had to lock in progression. Is there anyway to manually disengage the lockers. My dealership here knows less then I do, and I know next to nothing. So if anyone can help, please let me know. Thank you in advance.
 

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2000 G500 NMLE
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Sfak - 5/6/2005 6:40 PM

Please pardon me if my wording on this stuff is wrong. My differential locks wont disengage. My middle locker is engaged and the front locker are engaged and my rear lockers are not engaged. I didnt even think this was possible. I thought they had to lock in progression. Is there anyway to manually disengage the lockers. My dealership here knows less then I do, and I know next to nothing. So if anyone can help, please let me know. Thank you in advance.
It sounds like you may have some sticking solenoid valves. Try unhooking the vaccum lines to the solenoids and see if it helps. The center diff is pure vacuum. The front is hydraulic activated through a vacuum operated intensifier.

I can send you a schematic of the system if you'd like. Send me an email, as it's a PDF file.
 

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1996 G300TD
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Had this once on my '96 G on the front axle. VERY inconvenient trying to get home on hard surface.

I did as DUTCH suggests: pull the vacuum tube from the solenoid that sits in the engine bay. I had to replace the solenoid to cure the problem.

What confuses me though is the fact that you have multiple lockers sticking. It would be kind of funny when multiple solenoid would fail at once.

JW
 

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jwmol - 5/6/2005 7:25 PM

Had this once on my '96 G on the front axle. VERY inconvenient trying to get home on hard surface.

I did as DUTCH suggests: pull the vacuum tube from the solenoid that sits in the engine bay. I had to replace the solenoid to cure the problem.

What confuses me though is the fact that you have multiple lockers sticking. It would be kind of funny when multiple solenoid would fail at once.

JW
If an intensifier diaphragm failed and sucked brake fluid up into the vacuum lines, anything is possible. It could foul and plug the small filters on the vacuum relief lines on the other leg of the solenoids.
 

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DUTCH - 5/6/2005 7:28 PM

If an intensifier diaphragm failed and sucked brake fluid up into the vacuum lines, anything is possible. It could foul and plug the small filters on the vacuum relief lines on the other leg of the solenoids.
I've actually had this happen when I bought mine...
I had to replace both the front and back vaccuum valves. One Intensifier was bad too.

Chuck
 

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1989 G230
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Braingears - 5/8/2005 10:36 PM

DUTCH - 5/6/2005 7:28 PM

If an intensifier diaphragm failed and sucked brake fluid up into the vacuum lines, anything is possible. It could foul and plug the small filters on the vacuum relief lines on the other leg of the solenoids.
I've actually had this happen when I bought mine...
I had to replace both the front and back vaccuum valves. One Intensifier was bad too.

Chuck
Do you guys have the electric dif locks or the ones line in mine that you have to be a body builder to pull up? I like that mine don't have the computer telling them to engage.
 

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463 Diff Locks

oldg - 5/18/2005 5:09 PM

Braingears - 5/8/2005 10:36 PM

DUTCH - 5/6/2005 7:28 PM

If an intensifier diaphragm failed and sucked brake fluid up into the vacuum lines, anything is possible. It could foul and plug the small filters on the vacuum relief lines on the other leg of the solenoids.
I've actually had this happen when I bought mine...
I had to replace both the front and back vaccuum valves. One Intensifier was bad too.

Chuck
Do you guys have the electric dif locks or the ones line in mine that you have to be a body builder to pull up? I like that mine don't have the computer telling them to engage.
The 463's don't have a computer telling them when to engage, but the electrical system only allows them to engage in the sequence: Center - Rear - Front. You can disengage them in the same order reversed, or disengage the center which disengages them all at the same time.

There are electric switches which open vacuum solenoid valves. The vacuum comes from the engine manifold and an auxilliary vacuum pump. The center diff lock in the TC is purely vacuum operated. The front and rear are vacuum operated to intensifiers which feed the front and rear with hydraulic/brake fluid to the diff lock slaves under higher pressure.

A vacuum greater than 400 mbar engages the difflocks. The intensifiers bump the hydraulic pressure up to 15 bar.

The 460 diff locks are a lot simpler, they work as well or better and they can be engaged in any order, regardless of whether you're in 4WD or not.
 

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1989 G230
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RE: 463 Diff Locks

DUTCH - 5/20/2005 4:07 PM

oldg - 5/18/2005 5:09 PM

Braingears - 5/8/2005 10:36 PM

DUTCH - 5/6/2005 7:28 PM

If an intensifier diaphragm failed and sucked brake fluid up into the vacuum lines, anything is possible. It could foul and plug the small filters on the vacuum relief lines on the other leg of the solenoids.
I've actually had this happen when I bought mine...
I had to replace both the front and back vaccuum valves. One Intensifier was bad too.

Chuck
Do you guys have the electric dif locks or the ones line in mine that you have to be a body builder to pull up? I like that mine don't have the computer telling them to engage.
The 463's don't have a computer telling them when to engage, but the electrical system only allows them to engage in the sequence: Center - Rear - Front. You can disengage them in the same order reversed, or disengage the center which disengages them all at the same time.

There are electric switches which open vacuum solenoid valves. The vacuum comes from the engine manifold and an auxilliary vacuum pump. The center diff lock in the TC is purely vacuum operated. The front and rear are vacuum operated to intensifiers which feed the front and rear with hydraulic/brake fluid to the diff lock slaves under higher pressure.

A vacuum greater than 400 mbar engages the difflocks. The intensifiers bump the hydraulic pressure up to 15 bar.

The 460 diff locks are a lot simpler, they work as well or better and they can be engaged in any order, regardless of whether you're in 4WD or not.
Wow, that's alot of information. All I knew what that you have to use them in a special order. Now I know exactly how they work.
Thank you
Sean
 

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RE: 463 Diff Locks

... that is unless you have the switch box re-wired so you can engage in any order...

It's probably not the easiest job, but certainly doable. One thing i learned (since mine has been re-wired) is that you don't need that vacuum pump to engage the front or rear lockers, makes me want to de-activate the vacuum pump entirely (put it on a switch) so i only activate it if i want to... no sense in stressing the lines more than necessary... especially since more than one person has had the vacuum pump do more damage than good. The box also has an ABS kill switch pin on it... ground the pin... no abs... so you don't have to drive around for hours on dirt roads with either ABS on, or your vacuum pump running with your center diff locked.
 
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