chiph9

Your center differential is locked. Push the button to unlock it while SLOWLY moving forward. Do not drive it until you can get this unlocked.

What happens is when it's locked, the front and rear axles are mechanically locked together so they turn at the same speed. This is tremendously useful off road. But you can only use it on low-traction surfaces (dirt road or in a field, etc). Using it on a high-traction surface like a paved road means that torque builds up in the axles. One of two things can happen - the tires slip (like happens when off-road), or something breaks (axle, transfer case, driveshaft, etc).

If the 4x4 lock icon is off on the dashboad and you still have this problem, get it towed to a mechanic who knows 4WD systems, and ask them to manually release the center differential lock for you. DON'T DRIVE IT.

Chip H.

Benjam1n

Just swapped out o-ring on actuator today. I didn't unplug it because I couldn't get the clip to release the plug. Put the truck on 4 ramps. Couldn't get the 4th screw out of the actuator "cover" so I just left it on. Used an extension to get the three 12mm bolts and the actuator pulled right off the shaft, which remained in the transfer case, luckily. The actuator was not heavy and was easy to handle. Swapped out o-ring easily using a tiny flathead screwdriver, but the old one didn't look to bad, maybe a little flat in a few spots. Tiny trickle of fluid came out when I removed it. Had to wiggle the actuator a bit to get it flush with the transfer case. Bolted right back on. Checked fluid in transfer case, it was fine. I read this thread and the ih8mud thread on this several times and finally ordered the part on ebay. Both high and low range working fine, no check engine lights. Time will tell if it stops the leak. Appreciate everyone posting their experiences here, made doing it very easy for an amatuer such as myself.

Mauko

Sorry to resurrect an old post but I have this exact same transfer case actuator on my 2006 Lexus GX470. Does anyone know how to time/clock it?

In chasing down a P2772 code, I took the cover off of the actuator and the gears popped out. To try to fix it I decided to fully remove the actuator (while leaving the metal rack shaft inserted into the transfer case). I was able to easily get the actuator off the shaft that goes into the transfer case (probably because the gears were now loose). I put the actuator on my bench and checked the assembly and motor (by driving it with a 9V battery). The motor spins freely. I did not see any broken gear teeth, plastic bits or other issues. No oil or rust inside the actuator either. Everything looked good and it appears to operate properly.

The question now is how to realign the gear mechanism properly. There are a total of four gears in there, and it appears that only two must be correctly aligned: the large gear with the metal spring on the bottom of it that drives the rack shaft going into the transfer case and the small blue/white timing gear on the actuator cover (you can see it has a pointer under the metal viewport cover on the actuator cover).

You would think there would be some info from Lexus/Toyota on timing the actuator but I cannot find any. If your vehicle is having any issues with the actuator, the technicians tend to want to replace the entire actuator by dropping the transfer case and splitting it open (big $$$).

When I had it on the bench, I replaced both the large O ring with the correct Lexus part as well as the small oil seal (from Rocket Seals) that goes around the metal rack shaft.Thanks for the advice on this forum for this part as it seems to fit perfectly.

Since this went down, I decided to try to reassemble the actuator gears while the actuator was on the vehicle. I decided this for two reasons: the actuator had already been disassembled and by placing the gears while the actuator housing is on the transfer case, you don't have to do the twist/grind method of reinstalling the fully assembled actuator.

I devised this: I put the actuator on the transfer case without the gears installed, then I put the gears in place -- orienting them by trial and error -- and hold them there with a skinny screwdriver while placing the cover on the actuator (I am on my back working under the vehicle and the gears have a tendency to not want to defy gravity and fall out). The actuator itself is not tightly bolted to the transfer case at this time because the cover must clear a bolt housing on the transfer case and you have to slightly tilt the actuator housing to get the cover to go on. Once the cover is on, I hold it secure with three screws (temporarily), tighten up the three 12mm bolts holding the actuator to the transfer case, then install the wire plug and vacuum hose. I have successfully done this several times: loosen the 12mm bolts, remove the actuator cover, align the gears a certain way, and reverse the process, each time trying different gear alignments. (I am happy to provide my procedure sequence if anyone is interested).

The problem I am having is that when I have the actuator in place, I turn on the vehicle and engage the CDL button, but the dash light blinks. I'm thinking the center diff is not being fully engaged. Then, I click the button off and turn off the vehicle. I crawl back underneath and disassemble the actuator (while in place) to check the orientation of the gears, I notice the rack shaft has not been fully inserted into the transfer case.

It is my understanding that when the rack shaft is fully inserted into the transfer case, the center differential is UNLOCKED (CDL button OFF). When the shaft is pulled out of the transfer case to its stops, the center diff is LOCKED (CDL button ON).

When I do this procedure, I am reassembling the gear mechanism with the shaft fully inserted into the transfer case (because the CDL button is OFF when doing this).

So my question is, what is the correct alignment of these gears? There appears to be a mark on the large gear with the spring and nearby on the case housing. There also is a mark on the small blue/white gear and on the actuator cover it sits in. I have tried these positions, but I'm still left with the shaft not fully inserted after testing the CDL button.

I think if I could simply see some photos of the position of the large gear (with metal spring) and the small blue/white timing gear on the cover from good actuator while in the CDL OFF/UNLOCKED position (shaft fully pulled out of the actuator) would be all I would need to fix this issue and save thousands in repair costs. From what I can tell., the only critical gear positions are the large gear with spring (connected to the shaft) and the small blue/white timing gear.

Does anyone have any photos or could provide advice? Thanks in advance. I am new to this forum -- my first post!

nike23

I have an 03' GX470 and my transfer case is also "seeping" a little. I wrote Lexus corporate and they told me to take the vehicle to be diagnosed by the dealer. Once the dealer made the diagnosis there was no relief from Lexus whatsoever. $1000 would be the cost to fix the leak. My local mechanic said that what I was seeing was a splash leak, trans fluid in the transfer case was at the level where it was pretty much flush with the fill plug. Once the level is lowered beneath the plug the leak should slowly stop. I only get about a quarter sized drop in my driveway after coming back from an errand and I never leave any fluid while I'm out (that I can see). The vehicle has 119K miles and I really can't justify $1,000 right now to fix this issue. Would spraying something like one of those spray on leak stoppers around the area where the seepage is seen cause any damage? I know I would have to worry about heat but Other than that would this be advisable?

89OLDMAX

I am looking to buy a 2003-2008 GX470 core transfer case to tear down and experiment with. I want to see if it can be converted to a manually operated case. I live in Tomah WI and would pick-up within a reasonable distance. Bob at 608-387-1945

gxman1

I read iH8mud, Russian sites and all of the threads regarding this and RTFF

Some misinformation clarificaion:
1. Transfer case takes gear oil not Tranny Fluid in our GX
2. Our GX has one rod going into the actuator the 4runer has two.

My question are the following,
Leak is coming from the electrical connection harness, it is sitting at the highest point, so I dont think fluid travelled upward. I am guessing the Seal is broken and gear oil is filled in the Actuator motor.

I read here and elsewhere the actuator is factory filled with the transmission oil, however all of the pic I am seeing they look clean and dry internally am I correct it is not filled?

I had the O ring replaced by toyota mechanic last year. I am assuming it took a year to refil the actuator and now its leaking again.

I checked last night my Differential lock button and Hi Lo shifter all works fine. Differential locks takes about 10 seconds.

I am assuming changing the Seal and O ring should fix the issue? What about all of the fluid in the Actuator box, I will drain it via the seal hole, do I need to open it? Should I spray some brake cleaner on the electrical harness?

Please help.

89OLDMAX

The two actuators I have had off were not filled with oil. I do not think the oil in there will effect anything. Drain out the excess and replace the seals.

gxman1

Seals are coming today, just waiting on the FEDEX, O ring on hand. I will pull it out, drain much of oil out, and clean out the wiring harness from outside. I wont open the Actuator case. Any tip of how to pull and put the Seal, should I tap it lightly with rubber mallet?

89OLDMAX

I have only replaced the o-ring, so I can not advise on the seal

gxman1

I completed the job, pulled out the actuator.

1. Took off 3 bolts and disconnected the wiring harnes at actuator and the vent tube.
2. Pulled back, it came out about an inch and was stuck, slowly turned counter clockwise and kept pulling and it came out no crackling sound.
3. The actuator was full with oil, I drained it via the rod hole, gave it a good cleaning on the out side, and let the inside oil drain for an hour. Cleaned the connector both side the harness and at the actuator.
4. pulled the seal out, previously stupid mechanic changed the seal to wrong size it was only 3MM tall as opposed to 7mm. Upon close inspection saw inner lip was also bad.
5. Installed the new O ring and new seal, tapped it with the wide socket placed over outside of the seal into the the actuator.
6. Put grease on the teeth of the shaft, and greased up the Seal opening, and lightly coated the O ring, renstalled it. I put some dilectric grease on the electrical connection.
7. Lower the truck off the ramp, once leveled checked the transfer case oil level.
8. Made sure there are no residue of oil, gave it a good cleaning.
9. There is a protection plate underneath the transfer case and when you pull the actuator out, the oil spills and pools into the protection plate, make sure to clean it out, it is held by four bolts, otherwise you may think a dropped oil from there is from the actuator.
10. Easier than an oil change ..slow and careful.

11. Drove it around the block, when I was close to home, I stopped and pressed the differential lock button and prayed, it locked up so fast withn 2 seconds, it was taking over 20 seconds yesterday, I guess being full of oil had to do something. Drove it slowly and made 1 hard left turn and can feel the wheels binding, didnt want to do this, since I was not on gravel or wet surface, but curious to see if it works. All good. Turned off the differential lock.
12. stopped the truck, put in N and changes the Hi Lo to put in Lo and put the car in drive and drove no issues. Stopped the truck, put the shifter in N and put the car back at normal Hi position and than to D and was done. All good.

If you take to a mechanic make sure you see what the heck he is doing, and inspect the part he takes out, On a Previous job I paid shop around $200 for this easy job by "Toyota/Lexus Mechanic" for a professional job. he not only used a thinner seal he over charged, If some mechanic is doing this, it should not cost more than $75. Its a 15 minute job, all you need is 12MM socket, and an extention, rags, bucket to catch oil when opening, $3 seal , $4 O ring from Dealer, can of brake cleaner, ramp and wheel chock and a pair of glove. I took my time and made sure all of the oil was out of actuator.

89OLDMAX

It is nice to have the satisfaction the job is done right by doing it yourself, and you save money too boot.

gs03hlp

.

Thank you so much for this. do you still remember the part number for the rack Oil Seal of 2004 GX470 ?
I think this is a common issue and there is no You tube video. I think you will have many views as well as helping lot of people fixing this issue.

gxman1

15mm ID x 23mm OD x 7mm Height Spring Loaded Buna N Rubber Sealing Lip Seals in Grease and keeps surface clean Double lip (THEY ARE Buna N aka NBR seal)

I like NBR type since they belong to rubber clasification and the PTFE belongs to thermoplastic classification. The NBR in my opinion is a better material for this applicaion, it surpasses all characteristic if PTFE with the exception of Density.
http://www.oringsandmore.com/oil-sha...rice-for-1-pc/ order 3 seal for $8 plus shipping. This supplier is called Oringsandmore

Also,, RocketSeals sells it also call them and give them the size 1.800.445.7803

And you need also.
O, ring from Toyota dealer or online part # 90301-56009 about $4

Also get: Fill/Drain plug gaskets/washers which are a couple of bucks each from Toyota (part number: 90430-18008). These are not required and the old ones can be reused of they are still in good shape. Because you would need to check the level of oil from transfer case.

gs03hlp

Thank you very much for the part number and recommendations for preventing future issues. Do you have some type of pictures/videos how to change the seal ?

gxman1

[QUOTE=gs03hlp;10091830]Thank you very much for the part number and recommendations for preventing future issues. Do you have some type of pictures/videos how to change the seal ?[/QUOTE

Sorry, I dont have any, but it is simple job.