Doesn’t always switch out of 4H

So not all the time. But frequently enough, when I try to switch from 4H back to 2WD, the indicator light starts flashing, but it doesn’t complete the switch and stays in 4H with the indicator flashing.

Sometimes it’ll just take a half minute or so. Other times it just doesn’t do it. I’d say maybe a quarter of the time, it works as I’d expect.

I’ve only had full time 4wd before (4Runner), so not sure if this is normal and expected behavior. I read the manual a while back and didn’t see anything particularly helpful. I don’t use 4wd very often, but expect to a lot more over the next several years for a variety of reasons. And since I’m at 83k miles and my warranty runs out at 100k, I thought I ought to dig into this.

Thoughts?

 

I find that when switching either to or out of 4h, it seems to happen much faster when I let off the gas. Which makes sense, as it takes the tension off the gears and allows for a smoother disengage or engage. You may see smoother switches with some fresh differential oil though.

 

Are you rolling while switching or at a dead stop?

For me at least, if the truck is rolling a bit while I’m switching, then I’ll let off the gas and it’ll switch over pretty quickly.

 

I’ve tried both rolling with and without gas, and dead stop. I agree with @Danman34 it works a little better without gas. But the problem is consistent enough across all scenarios that I can’t help but wonder if it’s something else.

 

Could be a sticky actuator. Wouldn’t hurt to pull the actuator plug and make sure there’s no corrosion as well.

 

I was going to also reply w/possibly trying a drain n fill on the differential if you haven't done so already. However, w/that being said, I do notice that my '08 transitioned much smoother and quicker than my '21 Pro does (particularly when switching back to 2wd)...

I'm not sure if that's due to more electronics, etc. but I'm just hitting 15k miles on my '21 so fluid condition shouldn't be an issue for me.

Being off the gas doesn't seem to make mine disengage any faster either. So, I'll generally come to a stop before switching back to 2wd when conditions permit.

 

Do you/have you exercised it regularly? I know lots of people skip it and then somehave issues getting into or out of 4x4. @Tripleconpanna 's suggest fluid swap if you haven't already would be my go to.

 

Something else I just thought during my brainstorming on this issue...

Since our later 2.5s are prone to needle bearing issues (sloppy driver's side CV), is it possible that a little bit of slop in the CV would cause hesitation in the electronics as it's trying to transition???

I wonder if anyone here that's done a needle bearing fix has seen the hesitation eliminated after that repair has been done??

 

Have you owned the truck since new? The 4x4 system needs to be exercised regularly to be able to switch in and out properly. Most problems are caused by it never being used and then trying to use it. Also if the transfer case fluid has never been changed I'd look into changing it. If it has been changed and was done by a dealer they most likely put 75w90 in it instead of the required 75w which is much thinner than 75w90 which can cause issues when switching in and out during colder temps.

 

I’ve used my 4x4 pretty much every time I drive in the tundra and have always noticed the 2021 model hesitation to go in/out of 4x4. As others have stated it seems to like rolling forward in Drive with minimal acceleration. Often will not switch when in park at all. Also doesn’t seem to switch when turning. I appreciate my FJs torsen dif more and more each day (same for the sequoia and 4runner models that have a similar setup).

 

I exercise it at least monthly for a few minutes into 4H. Once in a longer while into 4L.

 

No. I bought it from Dublin Toyota in CA on New Year’s Eve 2021 with about 25k on the odometer. I’m the second owner.

I exercise it at least monthly in accordance with the manual’s instructions. But I’m not sure if or when those fluids were last changed.

 

Yep the more you switch it the more it switchs off quicker

 

I'd definitely swap the fluid. Especially if you use it pretty regularly.

 

Have you tried putting it in reverse and backing up a few feet after switching to 2wd? On the rare occasion mine hesitates to switch it works for me.

 

Frequently. Doesn’t seem to help.

 

Ha, I thought I was the only one with 4runner, that rear locker only worked 25% of the time, I can pressed the damn button and by the time it's engaged I no longer needed it.