Another center diff locking problem...

[Kbug]

Thanks for the help everyone, I finally got it to unlock! After testing the CDL button and relay (both checked out fine), I wasn't looking forward to crawling under the truck to test the motor since its been raining all day. Figured I'd give it one more go shifting between Low and High and sure enough after maybe 10-15 shifts I heard a clunk and it finally disengaged. Tested it a few more times and it seems to be locking/unlocking smoothly now. I'll be sure to exercise the diff lock regularly from now on!

 

[Kbug]

Sadly another thread update. I've used the CDL several times since my last post and it has lock/unlocked no problem every time since. Today I took my truck on it's first ever real offroading trip (SUPER impressed with what this truck can do stock btw, I was able to hang with decently built Jeeps all day). Anyway, just my luck when I engaged my CDL on the trails it decided to get stuck engaged again After literally spending about half an hour in the parking lot driving forward and back, turning the truck, hitting on the CDL motor with a hammer, etc I finally gave up, threw my hazards on, and drove 40mph on the interstate for 5 hours to get home. Too pissed off and tired to get into it tonight but looks like I'll have something to do tomorrow

 

[TheMU]

So, at least it seems like it doesn't want to dis-engage when it's been on load. What's the condition of the Oil in the T-case? When was it last changed? Crappy fluid can cause the actuator to not move.
Also, do you have Front and Rear Lockers?
From my understanding of a Toyota Video that I watched, the CDL should only be used in an emergency, i.e when you have a wheel that is stuck. The Rears and Front should be used depending on the situation.

I don't recall but the CDL isn't locked when you put it in 4L correct?

 

[scrowley]

Unplug cdl harness at cdl. Get a 9v battery and make couple jumpers to hook it up. Give cdl housing a couple love taps before hooking up battery. This helps free up frozen actuator. Cycle back and forth a bunch. Worked for me multiple times on frozen units.
This method also bypasses all other safety switches that could be hanging you up.
Neutral safety switches can be taken out and bench tested. Spray with electronics cleaner and cycle by hand until operates smooth.

 

[scrowley]

Sadly another thread update. I've used the CDL several times since my last post and it has lock/unlocked no problem every time since. Today I took my truck on it's first ever real offroading trip (SUPER impressed with what this truck can do stock btw, I was able to hang with decently built Jeeps all day). Anyway, just my luck when I engaged my CDL on the trails it decided to get stuck engaged again After literally spending about half an hour in the parking lot driving forward and back, turning the truck, hitting on the CDL motor with a hammer, etc I finally gave up, threw my hazards on, and drove 40mph on the interstate for 5 hours to get home. Too pissed off and tired to get into it tonight but looks like I'll have something to do tomorrow

Dude....just have to remove front drive shaft when this happens. Drive as far or fast as you want...
Your viscous coupler is prob quite unhappy after that highway run.

 

[inkpot]

Dude....just have to remove front drive shaft when this happens. Drive as far or fast as you want...
Your viscous coupler is prob quite unhappy after that highway run.

Dont think the 92 has a VC??

 

[CJF]

Dont think the 92 has a VC??

Correct. Even if he did, the VC is by definition perfectly happy when the center diff is locked.

 

[CJF]

From my understanding of a Toyota Video that I watched, the CDL should only be used in an emergency, i.e when you have a wheel that is stuck.

I don't recall but the CDL isn't locked when you put it in 4L correct?

These are both incorrect statements.

 

[CJF]

Dude....just have to remove front drive shaft when this happens. Drive as far or fast as you want...

Ayup. One of my rigs has been rear wheel drive only (no front driveshaft) for several years now and many thousands of miles.

 

[Kbug]

I tried to remove the front drive shaft but I didn't have the right tools with me (needed an extension). I have it removed now just so I can still get to work this week.

TC fluid was changed no more than 3,000 miles ago but will be getting changed again this weekend when I get into it

 

[Mandrake]

Clearly, fu

cking with it doesn't work, so it sounds to me that at this point your options are,

1) buy some tools and get really good at r&r'ing your front drive shaft every time you wheel or need 4wd.
1a) optionally, you could throw some part time hubs on the front and just lock/unlock them and leave the drive shaft in place.
2) buy some tools and download the fsm, put your big boy pants on and pull the actuator assembly out to give it a thorough douching.
3) pay someone to do #2.
4) sell it.

 

[CJF]

I tried to remove the front drive shaft but I didn't have the right tools with me (needed an extension). I have it removed now just so I can still get to work this week.

Make damn sure you have the CDL switch in the ENGAGED position while the DS is out; wouldn't want to have the lock suddenly decide it's ready to disengage in the middle of your commute.

 

[Kbug]

Make damn sure you have the CDL switch in the ENGAGED position while the DS is out; wouldn't want to have the lock suddenly decide it's ready to disengage in the middle of your commute.

What would happen if it unlocked while driving with the DS out?

 

[Mandrake]

What would happen if it unlocked while driving with the DS out?

It'd be like bumping it into neutral. Except you'll have to come to a complete stop before you relock the center diff.

 

[CJF]

Ayup.

Nice bounce off the rev limiter if you're under any load...

 

[scrowley]

Dont think the 92 has a VC??

Thanks for correction. Missed the year part. My bad. I guess it doesn't matter much at that point. Just pull a shaft and go.

I broke a rear shaft once far from home. No spare. I have a PT case. I couldn't believe how it drove in fwd. Literally couldn't even tell a difference in paved roads.

 

[CJF]

Just pull a shaft and go. Unless your pulling rear then you would need cdl switch so you can roll fwd.

???
No difference in procedure between setting up to run w/out the rear DS as opposed to the front.

 

[scrowley]

???
No difference in procedure between setting up to run w/out the rear DS as opposed to the front.

Yeah. Duh. I really have newer 80 on the brain. I edited. Guess im Not used to the early 90s model. Ha

 

[CJF]

Yeah. Duh. I really have newer 80 on the brain. I edited. Guess im Not used to the early 90s model. Ha

How would the procedure differ on a later model 80 series?

 

[scrowley]

With a VC you need to lock the cdl to use just front or rear so the VC doesn't overheat/fail. I'm thinking with no VC on early 80s you don't have to lock the VC because there isn't one. If I'm way off correct me.