Avoid the problem of 4WD disengagement while driving off-road due to vibrations.

[FJ62087143]

Avoid the problem of 4WD disengagement while driving off-road due to vibrations.
The root of the problem lies in the design of the lower transfer case arm. When the 4WD is engaged, it is close to the transfer case housing, causing strong vibrations to cause it to rub against the housing. This results in the arm moving in the opposite direction, effectively disengaging the 4WD. Toyota has updated and improved the arm so that it is bent and further away from the transfer case housing. This part is available from Toyota, part number (60080 - 36340). Good luck! (Photos attached)

 

[CruiserTrash]

Photo of the new one installed?

There is a Toyota TSB related to this that suggests replacing the detent ball springs. The EPC pulls up the TSB part number. Those were available 12 months ago when I last got some.

 

[FJ62087143]

Photo of the new one installed?

There is a Toyota TSB related to this that suggests replacing the detent ball springs. The EPC pulls up the TSB part number. Those were available 12 months ago when I last got some.

Thanks for the info! Here is the photo of the new one after installation (36340-60080).
Gooood Luck ...

 

[Spike Strip]

The -60080 is the standard part for 11/84-87 FJ60/BJ/HJ

The -60100 is for 70-series with 1HZ

 

[FJ62087143]

The -60080 is the standard part for 11/84-87 FJ60/BJ/HJ

The -60100 is for 70-series with 1HZ

No problem, my friend. Just make sure the part currently in your car looks exactly like part 60100. If it matches, you can safely replace it with part 60080. Don't rely solely on what the parts catalog says; my 1988 GCC-spec FJ62 came with part 60100, and I successfully replaced it with part 60080.
Thanks for the info and your attention .

 

[LazarusTaxa]

Interesting.. I rebuilt my transfer case with pretty much all new parts except the case halves and gears, including a new -60080 transfer linkage, bushings, detent springs, etc. And, it still pops out of 4wd regularly. While I haven't fully investigated it, i have no idea why it does this.

 

[FJ62087143]

Interesting.. I rebuilt my transfer case with pretty much all new parts except the case halves and gears, including a new -60080 transfer linkage, bushings, detent springs, etc. And, it still pops out of 4wd regularly. While I haven't fully investigated it, i have no idea why it does this.

Thanks for sharing your experience! Since you changed the detent springs, the issue is likely a linkage adjustment problem—especially if the car has a body lift, or if the shifter rubber boot and floor console are blocking the lever from engaging fully. Otherwise, it's wear on the original gear splines (worn taper) causing it to slip under load.I highly recommend starting with the easiest and cheapest fixes first: disconnect the linkage, remove the rubber boot/console, and shift it manually at the case to isolate the problem before looking into the internal gears.
GOOOOD LUCK

 

[LazarusTaxa]

Thanks for the tips. I have done basically zero to diagnose the issue, so this is an excellent starting point.

 

[Spike Strip]

This TSB about the Detent springs is also important:

 

[FJ62087143]

This TSB about the Detent springs is also important:

View attachment 4186472

Thanks for sharing! My recommendation was just based on my personal experience and what worked for my car when replacing part 60100 with 60080. However, adding this TSB—which CruiserTrash also mentioned—is very important. I’ve included a photo of the new spring part number (90501-16115) from the document so everyone has an official resource and another great solution to look into.

 

[DFXR]

Thanks for the tips. I have done basically zero to diagnose the issue, so this is an excellent starting point.

Have you checked your engine mounts? Driver's side, specifically. A broken mount can cause the t-case to jump as well. I figured this out after replacing the detents and springs to no avail. Replaced the driver's side engine mount and it solved the issue. It's sort of under the PS pump. Lots of threads about replacing mounts, some guys get to it from below and some from above.

You can test for this - when you accelerate from a stop in 1st gear, does your (trans) shifter swing to the right? If so, your mount is probably broken.

 

[CruiserTrash]

Have you checked your engine mounts? Driver's side, specifically. A broken mount can cause the t-case to jump as well. I figured this out after replacing the detents and springs to no avail. Replaced the driver's side engine mount and it solved the issue. It's sort of under the PS pump. Lots of threads about replacing mounts, some guys get to it from below and some from above.

You can test for this - when you accelerate from a stop in 1st gear, does your (trans) shifter swing to the right? If so, your mount is probably broken.

Put it in 4low and hit the throttle hard. Does the fan blade spin into the shroud and make a loud buzzing noise? Thats my favorite test haha.

 

[John McVicker]

My test to see if the D/S motor mount is broken is this:

A) place a 2x4 block of wood under the left side of the oil pan.
B) with a bottle jack use the 2x4 as a jacking point.
C) jack the oil pan up a few pumps.

This way you can actually see if the motor mount is split and moves…if it is split & moves, it MUST be replaced.

 

[John McVicker]

And here is how I ‘fixed’ my motor mounts so they will NEVER split in half again. Followed another Mudder’s advice & it works. A few pictures to help make more clear.
A) buy a new but cheap motor mount
B) cut off both studs from the motor mount
C) drill a hole completely thru the motor mount
D) reinstall the modified motor mount using a long bolt.

Done. Again not my idea but it works. Did mine in 2017 & still good.