97 FJ80 CDL or front locker problem?

[jerzjer]

I have a 1997 LX450 with stock lockers front and rear. I am having problems getting either the CDL or the front locker unlocked. I do not have the switch on the dash so the CDL locks automatically when I shift to low range. Everything looks like it is working properly according to the indicator lights for the CDL and lockers that are located on the dash. When I try to make a sharp turn or circle the front tires grab and make a sqeeling sound like the CDL or front locker is engaged. Is there a way to tell if this is the CDL or front locker? "My guess is the CDL because I can still drive it on the street and it feels normal other then when I am turning very sharp" Also is there a manual way to turn off the CDL or locker. I am not driving the car until I repair it to prevent more damage.

 

[subzali]

If your CDL light is solid and not blinking it is engaged. If your front locker is solid and not blinking it is engaged. The rear locker has to be engaged before you can engage the front (you have the dial correct? If you don't have the dial to the left of the steering wheel you don't have front or rear lockers).

If you have any or all of the lockers engaged on the street your tires will scrub when turning. You do not want to have any of them engaged on the street as that exerts tremendous pressure on the drivetrain when turning.

You can disable the auto-locking of the CDL by doing the so-called Pin 7 mod. Do a search for it. But if you do this you will need a CDL switch for the dash as the Pin 7 mod disabled the auto-locking of the CDL when shifting into low range.

It doesn't sound like you have a problem to me, just normal operation

 

[RyRoRyan]

Lift the front and then try to spin the tires by hand. If the other one turns in reverse then it is the CDL as the front locker is free and the diff is working correctly. If you cant turn it at all, then the front locker is still locked up.

 

[ppc]

A seized viscous coupler in the tail housing of the transfer case will exhibit the same behavior as locking the CDL. By chance are all the tires the same size and similar wear? Mismatched tires can cause the failure of the viscous coupler.

 

[jerzjer]

Yes all the tires are the same. Is there a way to check the valve?

 

[ppc]

It's not a valve. I suggest you do some searching to gain more knowledge. I believe you should be able to remove one of driveshafts and see if the LC will move forward. If it does that points to it being seized. If the CDL needs to be locked to move then look elsewhere.

 

[kevsta]

as the guys said, if either front or center were engaged, their lights should be on in the dash. if the front was engaged, the center would also have to be in first, and in fact, the rear too, because front comes next after rear on the dial.

if no lights are on or flashing, its unlikely the diffs are locked in. more likely the viscous coupler in that case.

 

[jerzjer]

Ok lifted up the truck today. When I spin the wheels on both front and back tires the other wheel spins in the other direction. So I guess next step is to remove the front driveshaft.

 

[Alic]

Why to remove driveshaft?
So you should do some things to understand how it is works.
Lift up ONLY ONE wheel. For example rear left.
Turn key to ACC, put your AT lever no N position. All locks are OFF. ALL lock indacators are off.
Try to spin lifted wheel by hand. The wheel should spin freely if you have open central differential.
The wheel will diffculty spin, but still spin! if you have viscous in central diff.
Vicscous is very usefull thing. It add much more stability on unsurfaced road at high speed. And it much more comfortable to drive in winter, it decreases slipping your wheel while you start to move on iced and snow roads.

Lift up 2 side wheels. One from front and one from rear.
Try to spin one of them. If you have viscous both wheels will spin, if no viscous then one wheel will spin.
Now turn key to ON position( engine stopped) and push CDL button (or move to low range )
Slightly spin one wheel. CDL should lock. You hear crank sound and both lifted wheels will spin together. (do this operation in silent to hear all sound - crancking of lockers and actuator motors are working)
CDL bulb will light.
If so then this step is ok. You should know, that CDL bulb do not have blinking option. It either have a solid light or
no light at all.
Also you should know, that front and rear computer get signal directly from that bulb. So if your CDL actuator works ok but. on\off sensor noesnt work and buld do not lighted then front and rear diff locks will not work.
So the point is that front and rear lockers do not work without CDL and its buld lighted.

Next step. If it is all works from above. Now you have two wheels lifted, remember?
Key is ON position. Lever is on N.
Turn rear diff lock. Now begin to spin rear lifted wheel. As lockers do not engage instantly you should spin rear wheel( while front\rear button if ON, but not engaged the bulbs wil blinking. Also they wil blink if sensor does not work).
While spining you should hear crank sound - and now cant be able to spin wheels, cause rear lock is engage. And as second rear wheel is standing on the ground, there is no possibility to spin lifted wheel by hand.
Rear locker bulb will light.
If locker is engaged and bulb doesnt light then disconnect gear sensor plug to the left of the rear differential. Make jumper from small part of wire and put it into plug from the wire side. As if your sensor closed. See rear locker bulb again.
If bulb lighted then rebulld or change sensor, if no light then see wiring from body to sensor and actuator. It often became a problem.

Now the last check - frond diff locker.
You should know rear and front lockers may engage independentelly, so if rear is not work and you try to turn on front - the front will engage even if rear bulb is not lighted.

You should check front locker as the rear one.
Lift up second rear wheel. Now one front wheel is on the ground. Now you have key in ON position. lever is on N. CDL locked bulb is lighted. rear locker button is on lock position. Doesnot matter engaged or not.
Try to spin one wheel if cental and rear is locked then 3 wheels will spin together in one direction.
Now turn front locker button in ON position. Try to spin wheel. You should hear crank sound and now you have no possibility to spin wheel by hand - all locker are engaged and one wheel that is on the ground prevent you to spin lifted ones by hand.
Do as above. If locker is engaged and bulb doesnt light, then check sensor with jumper. If it helps, then change sensor or rebuild it.
If no help, then see wire from underhood to actuator and sensor.
See carefully wires near the plugs. The isolation there often got crack and wires begin to corrode. If so then rebuld them or change.

Now you should hear on how all actuators are engaged.
All sound of motors should be silent and smooth. Without junk sounds. Speed of engaging all actuators should be the same. If one or more work with slowdown at the end - it is the signal to rebuild them.

So it is standard way to change all lockers without professional service. Hope it will help you.

 

[subzali]

Just reread your post. It looks like I misunderstood your issue. Do not try to drive with the front driveshaft removed unless you have your CDL locked. The viscous coupler will cause slow response and will be strained and you could burn it out if it's not already. With your current symptoms you could possibly have a burnt out viscous coupler. If no lights are showing on your dash your locks should be disengaged as there is a position switch that turns the lights off when they are disengaged. You can check manually though- there are threads with pictures of pulling off the actuator covers and taking a look. Good luck.

 

[LINUS]

I don't totally get what you're doing or trying to isolate/achieve OP, but to drive sucessfully w/o your driveshaft you need to use your CDL by shifting into low range & confirming it locks, then pull the fuse to keep the CDL actuator locked - then you can shift back into high range & pull the shaft.
Effectively making a 2wd Landcruiser.

It seems like from your description your not getting a locked axle up front.

It should be a pain comparitively to turn the wheel & steer on gravel, and really it is a bad idea to bind your drivetrain on asphalt.

If you had a locked differential, regardless of the CDL status, lifting one tire on an axle you shouldn't be able to spin it - just catch the limits of the locker for rotation.

If the other axle is on the ground you won't spin a driveshaft, so just shift to low range to make the permissive of the axle lockers happy. Beyond that if the indicators are working correctly they will go from blinking to steady, at that point jack up a tire & you'll have a wheel that you can't spin.

 

[jerzjer]

I did not remove the driveshaft. I raised one wheel with the ignition on and the trans. in neutral in high range. When I did this the wheel would not spin and I could hear the front axle trying to move. When I raised front and rear tires on the same side both wheels would spin. When I engaged the CDL by putting the shifter in low range and turning the dial to engage the front or rear lockers the wheels would not spin. Even though all the lights on the dash indicate everything is working properly I think the center lock dif is still locked.

 

[Sarge24]

I just picked up a 95 fzj80 3x locked yesterday and have been messing around with it trying to see if the lockers will engage so far I have been able to hear the cdl actuator motor moving and I am not getting an abs light or a cdl light on the dash. I pulled the abs fuse to see if the abs bulb happened to be out and the abs light came on... I have been reading as many threads as I can find and searching in my fsm trying to find exactly which sensor to check on the transfer case. Being a newbie I am having difficulty determining which one to pull out! I do have a 97 also that the cdl light does work so I know the sensor is good. I will just swap them to find out if the 95's sensor is shot! My problem is where is it exactly? I am thinking it is the one directly under the link from the transfer case shift knob. Is this correct? any suggestions on how to get it out? I am wanting to get this figured out and fixed so I can determine if the fr and rr lockers will work. Any help would be appreciated and thanks to all in advance!

 

[Sarge24]

I think I actually just came across what Ive been looking for thank you @sleeoffroad and @george_tlc

 

[Alic]

To get off CDL actuator or CDL sensor you should set up jack under tranny crossmember or transfercase.
Unscrew crossmember and slightly spool down jack. Tranny with transfer case will descent and you will have access to remove sensor.
Take a look to a engine fan behind the radiator while transfercase descentind.

But first of all look at the dash while bulbcheck. Wile bulb check - when you put in the key and turn it to ON position the CDL bulb must lighted wor a second. May be it is simply burned(broken)

BTW all sensors are the same - for the CDL rear and front.

 

[george_tlc]

^ CDL sensor (switch) can be removed without having to lower anything - there's room on the US auto equipped gasser to remove it fairly easily with everything else left in place.

cheers,
george.