Transfer Case Leak

[Highpockets]

Meant to include a pic of the OE plastic disc. The warpage is at the 2 thin webs, at the oval cutout.

Follow-up: the admin has set my attachment space limits too tight, so I can't post the 39.8 kb picture;

 

[KillerPea]

Hey guys...
I keep getting pms about the repair procedure and I apologize for not responding to each. I really don't feel comfortable trying to talk each individual through all of the little steps that are required to prevent damage to the actuator or the transfer case....I've taught several competent techs the process to skip a full overhaul, and in some case there was still consequential damage.

So...long and short....If you're near Dallas, contact me and I'll make it easy for you to drop your truck off for repair. shanemorrell@hatmail.cam is pretty close to my email. I've only got a few weeks before I start another business and won't have time to mess with this kind of stuff. If you don't live near Dallas.....try to find a solid dealership tech who has enough patience to install the updated oring without doing further damage.

Lastly....there is no need for the internal seal or any machined plates to complete this repair. Out of hundreds I've repaired, I've never seen another leak again.

 

[GXO]

I had mine repaired with this method at the Cherokee Toyota Dealership in Canton, GA. They have master Lexus techs and know the deal. Was $500 vs. the 1k+ spec'd by Lexus. Another option in GA. Took less than a day.

 

[470reasons]

Thanks for the post and info Dan.
How did the dealer do the repair? Pull/Crunch/Twist or tcase disassembly?

I’m in Wisconsin, but plan on getting rear coils, a lift kit, and rock sliders installed over at ACC in Scottdale. I see there are motels and restaurants near the Toyota place in Canton. This looks very doable!

Your posts are always informative. Thanks again.


2004 GX470
1991 CRX Si
1966 Datsun Roadster
1987 CRX

 

[GXO]

I actually asked him to describe it in detail and he let me watch some of it. He disassembles the actuator from the outside and leaves the rod in place. Basically, the actuator motor has a clip on the end attaching the shift rod and by opening it he was able to pull the motor without moving the shift rod. Then he replaced the seal and reassembled.

It was pretty damn straight forward and easy.

 

[lathamb]

Forgive my ignorance in advance, but what does this part actually do? If these are full time 4wd with a manual high/lo range shifter, whats the actuator motor needed for? My 80 has no such motor that i know of.

 

[GXO]

the actuator locks the center diff when needed (button) in High, and automatically in low.

 

[lathamb]

the actuator locks the center diff when needed (button) in High, and automatically in low.

Ahh cdl. Gotcha. Thanks. .

 

[shang0]

I actually asked him to describe it in detail and he let me watch some of it. He disassembles the actuator from the outside and leaves the rod in place. Basically, the actuator motor has a clip on the end attaching the shift rod and by opening it he was able to pull the motor without moving the shift rod. Then he replaced the seal and reassembled.

It was pretty **** straight forward and easy.

So you are saying he replaces the seal while the actuator is still connected to the transfer? By looking at pics of the actuator, i am not sure how that is possible

Actuator in Place:

Actuator Housing:

Actuator Internals:

 

[GXO]

So you are saying he replaces the seal while the actuator is still connected to the transfer? By looking at pics of the actuator, i am not sure how that is possible Actuator in Place: Actuator Housing: Actuator Internals:

Nope. He removes the actuator by disconnecting from the shift rod it is attached to in the case.

 

[470reasons]

So you are saying he replaces the seal while the actuator is still connected to the transfer? By looking at pics of the actuator, i am not sure how that is possible

Lol! I was looking at that same picture of the inside of the actuator earlier today. The rack is buried deep inside the gear train and would require major disassembly to get it free. So, the dealer is ACTUALLY doing the the pull/crackle/turn procedure everyone on the forums is talking about. Hmmm.

The timing mechanism is that flat piece of plastic on the left that is held in place by the 2 screws. It looks similar to timing mechanisms in some VHS VCR's! Undo any of the gears or the timing mech. and you'd d@mn well better know what you're doing.

 

[Blackhatch]

Any updates on this?

Sounds like the best way to go is to dissassamble the actuator and leave the rod in the case.

Who has the line on the seals?

 

[Highpockets]

Yeah, after removing the T-case myself and R&R the seal, I have an update....

The plastic nose plate's geometry at the end of the actuator assembly is the cause of the leak ; not to mention it's held to the nose by only one sheet metal threaded screw. Over time the plate warps, thereby increasing a radial portion of the O-ring's groove. Then the O-ring is allowed to move axially (bad), which allows the 90W oil to slip by.

Replacing the O-ring only delays the occurance til later. The plastic plate is the problematic root and must be addressed.

I lathed and milled my own *metallic* nose plate, with some increased thickness here and there. I have pictures but this beginner IH8MUD account won't let me post them. I also added a spring that pushes against the T-case female pocket bore AND conversely against my metallic plate, to compress the plate against the actuator's underlying nose. I also used a Viton O-ring instead of the Toyota stock neoprene ring which takes a set.

Now it's a test of time. I should know for sure in 30,000 - 50,000 miles if the re-design is appropriate. And a reasonable bearing and seal shop should be able to supply a new seal, albeit it will only be 7mm tall, instead of the stock 8mm height. If you want pictures, PM me or reply.

 

[Blackhatch]

Yeah, after removing the T-case myself and R&R the seal, I have an update....

The plastic nose plate's geometry at the end of the actuator assembly is the cause of the leak ; not to mention it's held to the nose by only one sheet metal threaded screw. Over time the plate warps, thereby increasing a radial portion of the O-ring's groove. Then the O-ring is allowed to move axially (bad), which allows the 90W oil to slip by.

Replacing the O-ring only delays the occurance til later. The plastic plate is the problematic root and must be addressed.

I lathed and milled my own *metallic* nose plate, with some increased thickness here and there. I have pictures but this beginner IH8MUD account won't let me post them. I also added a spring that pushes against the T-case female pocket bore AND conversely against my metallic plate, to compress the plate against the actuator's underlying nose. I also used a Viton O-ring instead of the Toyota stock neoprene ring which takes a set.

Now it's a test of time. I should know for sure in 30,000 - 50,000 miles if the re-design is appropriate. And a reasonable bearing and seal shop should be able to supply a new seal, albeit it will only be 7mm tall, instead of the stock 8mm height. If you want pictures, PM me or reply.

Pictures please. Feel free to PM me for an email address.

 

[Blackhatch]

Bump it up folks.

Where are guys sourcing the seals and the O-Ring?

 

[470reasons]

http://www.clublexus.com/forums/gx-first-generation/394711-transfer-case-leak-8.html

 

[B-RAD]

Is there anyone in the Denver metro area, one might recommend to work on this issue of a leaky transfer case on a 2004 GX470, besides a dealership??? I have a call into Slee, and one other shop. Thanks in advance!

 

[Jimlevin]

So, has anyone actually performed the repair without removing and without opening the transfer case AND by only removing the actuator box AND then ALSO been sucessful, AFTER THE REPAIR, in being able to go from high range 4WD to LOW RANGE four-wheel-drive and back without causing any errors or other synchronization problems?

I ask, because a post on Lexus forums says that repairing by only removing the actuator box breaks some of the plastic housing, the plastic actually guides the control arm that is inside the transfer case that actually locks the center diff, which causes a whole new set of problems with synchronization when going into low range 4 wheel drive. The broken actuator box them prevents you from being able to go into low range four-wheel-drive once the box is reinstalled, I understand it throws the synchronization out why Lexus requires the transfer case to be removed to properly take the box off. I understand the shortcut repair instructions, but by only removing the actuator box once done, it forces you to only be able to use high range four-wheel-drive, if I understand the post correctly, because the actuator box plastic guide rails are broken off when the actuator-box-only is removed by itself, that is the crunching and breaking noises, the actuator box plastic is breaking off, actually damaging the actuator box itself. Apparently it was never designed to be removed in that fashion, so removing it without opening the transfer case breaks parts inside the actuator box.

I have not been able to locate a post from anyone, unless I am mistaken, where the actuator box only repair has been completed and then the person was also able to go from high range four-wheel-drive to low range four wheel drive and then back to high range. I understand that if the actuator box alone is removed and reinstalled and then you attempt to go into 4 Wheel drive low range, the vehicle will display errors and you will not be able to drive nor be able to get back into high range without removing the transfer case and replacing the actuator box. If I am mistaken I apologize, any info would be appreciated on this. (take a look at the post on Lexus club forum, if I understand the pictures correctly, the twisting of the actuator box pushes the gears and the arm wider than what the guide rails will allow so something has to give, the guide rails break off or a portion of the guardrails break off inside the actuator box, which destroys four-wheel-drive low synchronization, and if you attempt to go from 4 Will Dr. to four-wheel-drive load the vehicle won't move nor is it fixable without dropping the transfer case).

 

[GXO]

I had mine done that way by a Lexus master mechanic...but he did it differently...I can shift fine.

 

[Jimlevin]

Thanks DanKunz. Just got a quote from Lexus stearlership at $1,204.00, he did try to justify price saying that they remove the transfer case and replace ALL seals and gaskets and do a complete overhaul.

Local Lexus mechanic shop, that is very trusted, quoted me $351.00. They have done work for me in the past and I was very satisfied, they tend to have many ex-dealership mechanics that work for them.

I will report back as soon as I know more. For $350 I will let the local Lexus shop perform this repair due to the possiblity of damage I could cause, not to mention I don't have a lift and would be lying under the vehicle. My concern is if the repair does not go well, as some have reported, my car would be stuck in the driveway & would need to be towed to a shop.