Front Diff Lock won't disengage - advice please!
Good morning, All
I am after some advice, please.
The G in question is a 463, LWB 300DT 1997.
The front diff lock has become engaged and it won't disengage.
I think the switch was knocked on by mistake (I wasn't in the car at the time...!).
There is no response from the switch itself, and I have tried driving a short distance in low range to no effect: the red light remains lit and the front wheels are plainly rotating at the same rate!
I want to start by examining the switch in case that has failed.
Can anyone advise now to get at the switch by dismantling the centre console?
Grateful for all constructive suggestions!
Thanks guys,
Geoffrey
Normally, the front diff is the last one to engage, only after the centre and rear are engaged, in that order. If the others are not engaged and only the front is remaining on, it may be that you have a fault in the actuator. Driving slowing (in high range) and turning the steering wheel left and right should help it dis-engage, but if that is not working, you will need to investigate the actuator on the front axle. You will need a copy of WIS for instructions on how to proceed.
Try to re-enage all the locks, starting with the centre one, followed by the rear and then, the front one again. There should be an orange light to indicate that they have been selected and the actuator primed, followed by a red light once actually engaged.
To disengage, press the switch, starting with the front lock, the orange light should go out and finally the red-one, once released. If you get the orange lights, the switches are OK,. The red light is operated by micro switches on the actual lock. if the red light remains on, after the orange lights are off, you have an actuator fault. That is, it is stuck.
You can try to raise the front wheels (axle) and give the actuator a tap with a soft mallet and see if that helps.
(The front diff lock switch will not respond on its own - only after centre and rear switches are first depressed. Each will then show an orange light followed by a red light when actually engaged. If you get the orange light, the switch is OK.)
You can only engage the diff locks in order centre, rear and front, so it appears that someone must have deliberately engaged all three. If the front yellow light is not illuminated then it has been disengaged electrically but has not mechanically disengaged. This is probably due to the front driveshafts being under pressure due to driving on a hard surface. The dog gear inside has not sufficient pressure from the actuator to disengage itself.
Do as Arnie suggests and raise one of the wheels off the road, put the transfer into neutral and see whether you can rotate the wheel by hand to release the pressure on the drivetrain.
Clearly you should not be driving it on a public road nor any hard surfacing
Good news, then!
I am guessing that your front diff lock may be a little sticky due to infrequent use.
The centre diff-lock operates quite differently on the transfer case, and I would not worry about servicing that one, as it's electronic anne does not rely on pneumatics and hydraulics like the front and rear do.
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Dear Arnie
Dear Roly
Many thanks for your wise words.
I tried all of these suggestions over several days, seemingly to no effect at first.
Finally today, however, when I came to try again, everything (I mean the red lamp on the front diff switch, and also the front diff itself) was back to normal.
I shall now get all three diff locks serviced before touching any of the switches again!