Difflock does not disengage!

[Brett Steyn]

Hello,

Can anyone perhaps help? I have a 2005 2.7l petrol with diff-lock. I for some reason can't get my diff-lock to disengage. Initially when I bought the vehicle, the diff-lock did not function so I replaced the solenoid valve in the engine area. I switch the diff-lock on and she engages after a little swerving around on the gravel road. When I switch it off, the diff-lock does not disengage but if you remove the pipe from the solenoid to the diff she only then disengages after a little swerving around on the gravel road. I took it to Toyota for a service and they had a look. They recommended I take it to an auto electrician. Can anyone help, any thought?

Regards,
Brett

[2.8 d/cab SFA]

It sounds like an air one. THere is a pipe from brake master to solinoid then another to diff. Before removing the pipe, did you try reversing a short distance first? Sometimes it doesnt disengage but if reverse it will unlock. I dont think it is an electrical problem if the solonoid is working.

[Mud Dog]

If the solenoid valve is clicking for both on and off positions, then it's not an electrical fault. the fault will be that the vacuum is not being relieved. Normally there will be a one-way valve in the line between the brake booster and the manifold and quite often guys will fit an extra one-way / non-return valve in the line from the brake booster to the solenoid valve (the one that feeds the valve with vacuum). If this valve for some reason has been erroneously fitted to the line going to the diff, tthen you will have that problem.

[Brett Steyn]

If the solenoid valve is clicking for both on and off positions, then it's not an electrical fault. the fault will be that the vacuum is not being relieved. Normally there will be a one-way valve in the line between the brake booster and the manifold and quite often guys will fit an extra one-way / non-return valve in the line from the brake booster to the solenoid valve (the one that feeds the valve with vacuum). If this valve for some reason has been erroneously fitted to the line going to the diff, tthen you will have that problem.

Thanks "Mud Dog" I appreciate the feedback. I will go have a look and see if I can locate this / these one way valves then!

[shaunmeizter]

I had the same problem with my 2003 2.7 2x4. I replaced the valve in the engine bay. Opened the old (broken) one to see how it works. When you turn on the difflock the electric current run and make it magnetic inside, this picks up a weight to "lock" the air, if you turn is off the weight drops again and free the air for the difflock to disengage. If you have the same one there is a rubber cap on the top, spray bit of anti rust or Q10 in and shake it to losen the weight it worked on my 1997 2.4 4x4 (exact same difflock).

[2.8 d/cab SFA]

yes mine was same "rubber cap on the top, spray bit of anti rust or Q10 "