Center differential explanation (1 Viewer)

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When I got my LX the CDL wouldn't engage reliably and it was a bit difficult to put the Tcase into low range. It was a one owner (Lady Owned) vehicle and no doubt had rarely (if ever) been out of high range or the CDL engaged.

Some driving around and exercising those functions restored them to like new and it all works buttery smooth now for the 5-6 years I've owned it.
 
More often than not....when a CDL won't engage its from inactivity. These Tcases are pretty reliable and are certainly robust in build.

I'd try to find a spot off-road where you can drive around at low speeds and try to activate it under various conditions (NOT at rest).

Try under light throttle, try at low speed and let OFF the throttle and as it begins to coast, etc.

IF you can get it to engage (and disengage which could be an issue) then continued use....should make it better.

Good luck.
Thanks so much!
 
When I got my LX the CDL wouldn't engage reliably and it was a bit difficult to put the Tcase into low range. It was a one owner (Lady Owned) vehicle and no doubt had rarely (if ever) been out of high range or the CDL engaged.

Some driving around and exercising those functions restored them to like new and it all works buttery smooth now for the 5-6 years I've owned it.
Thank you great idea!
 
When I got my LX the CDL wouldn't engage reliably and it was a bit difficult to put the Tcase into low range. It was a one owner (Lady Owned) vehicle and no doubt had rarely (if ever) been out of high range or the CDL engaged.

Some driving around and exercising those functions restored them to like new and it all works buttery smooth now for the 5-6 years I've owned it.
great suggestions really appreciate it. It was keeping me up at night. As far as Lexus Techs makes sense as technology changes and these LCs get old.
 
When I got my LX the CDL wouldn't engage reliably and it was a bit difficult to put the Tcase into low range. It was a one owner (Lady Owned) vehicle and no doubt had rarely (if ever) been out of high range or the CDL engaged.

Some driving around and exercising those functions restored them to like new and it all works buttery smooth now for the 5-6 years I've owned it.
It has been a few months and I am just getting back to this problem before
great suggestions really appreciate it. It was keeping me up at night. As far as Lexus Techs makes sense as technology changes and these LCs get old.
Thank you great idea!
Just getting back for ideas on this problem. CDL on my 2001 LX470 will not engage. Actuator and relay working. Fluid changed. Even the Lexus dealer tried and replaced the actuator and could not engage and did not charge me. Did S turns and donuts for 20 minutes on hard gravel road. Would love some ideas on where to go from here. Can it be coaxed somehow. It worked a year ago inadvertently when my knee kicked the button. Thank you
 
It has been a few months and I am just getting back to this problem before

The 'S' turns and donuts are unnecessary IMO. The Center diff is contained in the Transfer Case and is not directly influenced by turns (as the axle differentials are). BUT....'loading' of the Tcase (power applied under throttle) WILL have an effect. So I would recommend trying again. Driving a straight line and under modest throttle (or even coasting) try to get it to engage. IF the system is 'calling' for the action (button works if have CDL button, relay works, actuator works) then its simply a clearance issue. The gears/splines have not been used enough to 'wear in' and make reliable engagement possible.

I had to 'exercise' mine quite a bit to get it to work well. Even now...it will sometimes not engage first try when sitting still, but when moving slowly, and under light throttle it will do so every time. I also believe that engaging and disengaging the center diff while under light load (moving) helps the 'wear in' process. When at rest any gears/splines may not be lined up properly to allow them to engage (despite any bevels or lead-ins). Try again and IF successful....do it as many times as you have time for and periodically thereafter. Most of these problems are of mechanical nature from non-use.

DO check the voltage at the actuator as well....to be sure it isn't being compromised by low voltage.
 
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The 'S' turns and donuts are unnecessary IMO. The Center diff is contained in the Transfer Case and is not directly influenced by turns (as the axle differentials are). BUT....'loading' of the Tcase (power applied under throttle) WILL have an effect. So I would recommend trying again. Driving a straight line and under modest throttle (or even coasting) try to get it to engage. IF the system is 'calling' for the action (button works, relay works, actuator works) then its simply a clearance issue. The gears/splines have not been used enough to 'wear in' and make reliable engagement possible.

I had to 'exercise' mine quite a bit to get it to work well. Even now...it will sometimes not engage first try when sitting still, but when moving slowly, and under light throttle it will do so every time. I also believe that engaging and disengaging the center diff while under light load (moving) helps the 'wear in' process. When at rest any gears/splines may not be lined up properly to allow them to engage (despite any bevels or lead-ins). Try again and IF successful....do it as many times as you have time for and periodically thereafter. Most of these problems are of mechanical nature from non-use.

DO check the voltage at the actuator as well....to be sure it isn't being compromised by low voltage.
Love it thanks for your time! I have some better direction now and going to fix and exercise this thing into operation!
 
Here’s my ctr diff Story


Pretty much what you are experiencing. Pull shifter to low, I heard relay click, yet no lights.
Found switch that turns on lights, top front of xfer case, dead. Replaced it. Still no work even though relay click, motor on xfer whirred.
All circuits tested fine.
Ended up being someone had the actuator motor off the diff But installed it incorrectly. Motor would turn but because the shaft was not set properly and motor was not set properly when it was installed it failed to do its job.

HTH’s
 
How did I fix it you ask?😁
I removed actuator, engaged low, motor whirred to that position. Reached into xfer case, slid fork ahead to make light come on and verified xfer was now locked by spinning tire.
Re-installed motor with it in its locked position with xfer in its locked position.

System now works as designed.
 
How did I fix it you ask?😁
I removed actuator, engaged low, motor whirred to that position. Reached into xfer case, slid fork ahead to make light come on and verified xfer was now locked by spinning tire.
Re-installed motor with it in its locked position with xfer in its locked position.

System now works as designed.
Can you break that down a bit more? It sounds like you left the actuator connected to the vacuum line and electrical harness. Then shifted into low and then I’m lost.
 
Can you break that down a bit more? It sounds like you left the actuator connected to the vacuum line and electrical harness. Then shifted into low and then I’m lost.
I removed the actuator, physically shifted the Xfer into low with my finger. You may have to jack the rear and spin the tire with your foot in order to get it to shift into low.

At this point you can put a finger down the hole the switch goes in and you can feel the ramp which actuates the switch. You can put the switch in and hook it up and light should come on if the lever is pulled to low.

Hook actuator up electrically (still not mounted to xfer) and with lever in low it will motor the low position.

Now the actuator is in low position, xfer is in low position (shift fork wise).

re-attach actuator to xfer. Shift to high, lights should go out, shift to low, lights come on.
 

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