Rear locking differential

How do I tell by looking at differential from rear if it’s a locker? A small lever type device to right of ‘pumpkin’ with a fluid line over to drivers side of frame to something like a brake cylinder. sorry, best I can do my truck is 04 prerunner and wiring harness is present under dash with white flat 5 terminal plug but switch for locking differential is missing

 

The Toyota 8" diff with the electronic locker will have an actuator on the forward face of the axle housing/3rd member on the drivers side. It's electronic, so no fluid line- but there will be an additional wire harness to the actuator.

A somewhat easier giveaway, is the 8" diff has the drain plug on the drivers side, while the non-locking 8.4" has the drain plug on the passenger side.

Now there are after-market lockers for the 8.4", so it's not impossible that someone has come along and put an ARB air locker into an 8.4" axle/diff.

 

Thank you sir. Drain plug on passenger side so no locker. I guess they have wiring harness already in place for some tacomas

 

Just look at your rear diff; you'll see the actuator.

Otherwise, no actuator no factory locker.

Wiring exists for the indicator light on your dash, but it won't be there from your rear axle housing up to your cab.

You'll have an RR DIFF LOCK button next to your illumination dial, left of your steering column. Can't miss it.

But if you have "loose wires", well it could be anything given how old these vehicles are. Many people go on installing and uninstalling things throughout the years, especially with multiple owners involved.

It doesn't help that you didn't include a single picture at all either.

 

Just an example of shit I uninstalled in a short time frame from my vehicle; all done by the previous, or previous previous, or even more previous than that, owner.