Front/Rear Diff Lock (1 Viewer)

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Joined
Mar 11, 2006
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I tried to engage my front/rear Diff Lock according to the factory manual. But the light on the dash just blink and no solid light. I had the T-Case on Low but nothing still happen. What can be wrong. Do you guys think I need to re-build the actuator. Thanks for the Help.

I want to be able to pin point the cause w/o openning a new cans of worms:beer:
 
sometimes they need to be worked. Go find some soft soil and drive around (slowly) turn in a circle and they should engage.
 
I'll ask so others may help...What year is your rig? And I second the drive in a circle on dirt for a little while.
TR
 
P-Hog,

There are many posts in the archives detailing the process to test, debug, and repair the F,R,&C diff lock mechanism.

To test, you need to be on a low-traction surface; preferably gravel or dirt. Open windows so you can hear what's going on. Low Range and listen for center diff lock motor to whirr then you should get a solid center diff lamp. You may have to move forward a few feet to engage. Turn rotary knob to RR, then listen for the RR diff lock motor to whirr then you will have to drive slowly in an arc to enable the rear cogs to align and the rear to lock. The rear diff lamp blinking should stop and the lamp should remain lit. Turn rotary knob to FR, then listen for the FR diff lock motor to whirr then you may have to continue driving in an arc to lock the front and turn on the front diff lamp.

-B-
 
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yet again, drive slowly in circles
 
For the newbies:

The "drive in circles" comments might be a little misleading. After the locking mechanisms have been excersised a few times the locking becomes much quicker. You won't have to drive in circles on the trail to get your lockers engaged. Mine engage within 2 or 3 seconds on the trail and many times they engage instantly.

What is happening is that your rear wheels need to turn at a different rate to enable the dog clutches to engage. This can be accomplished by swerving left and right for a few feet. The rear locking cogs are much larger than the front so it may take a longer distance traveled in order to engage the rear locks.

-B-
 
Petrol, you say you're in low range but do you have the CDL switch & pin7 done? Doubtful, but worth asking.... your lockers won't engage if your center diff isn't first engaged, for good reason.

In stock config that should happen when you shift to low but most folks disable that feature.. though with two posts I'll take the leap and presume you're not there yet? anyway, worth pointing out.. I know I've wondered why mine don't engage sometimes only to later say *duh...
 
BTW, my rig is a 97 Lexo w/ the factory Front/Rear Locker option. I do not have the CDL switch and the 7-pin mod. OK guys I'll try driving in circle tomorrow and I'll keep you guys posted, thanks for the help.
 
Ok, I tried going in circles about 5 times with the lever in L. Then I shifted to D still nothing then to 1 and still nothing just blinking light on the dash. Am I doing it right? This would not have happen if I had the F/R Diff lock to work:crybaby: after a few rock back and forth I was able to get it out.
 
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I know i might be repeating what others have already said but...


The FR and RR lockers cannot engage until the center difflock is engaged. If you cant get your center to lock when you put the truck in low, that should be your first concern.

When i first started driving my 94 i would put it in low and turn the dial and just got the blinking lights like you said. It took a solid 10 minutes or so of throwing the t-case from high to low, just back and forth until finally the center light lit up.
 
Is your dash light coming on indicating that your Center Diff Lock is working/locked?

If not, maybe your low range sensor is bad (i am banking this is your problem):

Read this: https://forum.ih8mud.com/showthread.php?t=44416&highlight=Diff+Lock+Dash+Light

My rig had the same problem when i got it. Its an easy fix and that above link gives you a "Test" procedure for the indicator!

P.S. Where are you located at? If your in So Cal i can check it out for ya
 
Cruiserhead05 said:
It took a solid 10 minutes or so of throwing the t-case from high to low, just back and forth until finally the center light lit up.

I bet your indicator was sticking! :D
 
petrolhog said:
Ok, I tried going in circles about 5 times with the lever in L.

Follow the instructions in post #4 and report back with specific details to let us know what is happening.

-B-
 
from your post I can't help but wonder: Are you putting the *transfer case* into Low gear? Or just the transmission?

You've gotta have the transfer (the hi/lo lever) into low, not just choosing L instead of D on the tranny.

Then try the above.
 
Boston Mangler said:
Is your dash light coming on indicating that your Center Diff Lock is working/locked?

If not, maybe your low range sensor is bad (i am banking this is your problem):

Read this: https://forum.ih8mud.com/showthread.php?t=44416&highlight=Diff+Lock+Dash+Light

My rig had the same problem when i got it. Its an easy fix and that above link gives you a "Test" procedure for the indicator!

P.S. Where are you located at? If your in So Cal i can check it out for ya

I recognize that thread! :flipoff2:

I'll second Kevin's offer as would most of us on the board - where are you? Someone here may be able to help.
 
Get on something slippy an gun the gas for a second in first.
The slippage with help them slide into a lock.

Turning in circles will do it too.
What you need to so is cause the diff to slip allowing them to line up and enguage.

Once you work them a bit, the enguage easier and faster.

Cheers,
Nick
 
Brentbba said:
I recognize that thread! :flipoff2:

I'll second Kevin's offer as would most of us on the board - where are you? Someone here may be able to help.

I Third the sticking button switch in the trasfercase. I had this happen with my first FZJ, I picked up a new switch for it but never needed to put it in. I just kept cycling the lockers and it all started to work just fine. Keep at it, its just due to lack of use if this is the case.

Mark
 
sandcruiser said:
from your post I can't help but wonder: Are you putting the *transfer case* into Low gear? Or just the transmission?

You've gotta have the transfer (the hi/lo lever) into low, not just choosing L instead of D on the tranny.

Then try the above.
I have the Transfer in Low and still not getting any lights on the dash, I can feel that its on low when I drive it the motor grunts.
 
petrolhog said:
I have the Transfer in Low and still not getting any lights on the dash, I can feel that its on low when I drive it the motor grunts.

This is exactly what i was experiencing when my indicator was sticking!

where are you located damnit? :D
 
Sorry still trying to figure out this PM stuff to work. Rancho Cucamonga 91730. Kev, I tried jumping the wires to the sensor and still notin
 

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