I have a 1997 4runner Limited automatic with the 4WD/4H push button on the selector lever (which works fine, btw).

With the vehicle stopped and the transmission in neutral, I get a grind when moving the selector lever from H to 4L. If I slowly move the lever toward 4L, I can feel that gears are still turning (similar to bumping the shifter into a gear in a manual tranny w/out the clutch depressed...if that makes any sense). Anyway, if I grab the selector lever and purposely pull it into 4L, it moves right in, but with a slight grind. Moving back into 4H is the same.

Otherwise, everything works great when in 4H, 4L, and 4L w/rear diff lock.

This doesn't seem normal, and the one thread I found about grinding into 4L and 4H said it's most def not normal. So, any idea what's up?

Dave

 

no it is not normal

I ignore my issue by shutting off motor, shifting, starting again. problem worked around

 

...sadly, I do this too

 

I have the same year and model as you. Mine grinds also when in neutural. Try putting the tranny in park first.

 

Since the t-case gears aren't synchronous, moving the lever slowly lets one gear spin up while trying to engage with a stationary gear. A quick, firm throw of the lever will usually prevent any grinding.

 

If the vehicle is stopped and the tranny is in neutral as the OP said. Why would the gears in the t-case be turning at all?

 

My guess would be that with the auto there is enough spinning in the trans that the fluid has enough drag to make things spin. This transfers to the transfer case whan shifted. You go thru neutral on the transfer case to get to 4Lo. The longer you are in N the more it will spin. If you shift swiftly from 4Hi to 4Lo there should be less grind.

Does it grind more when it's cold out? When the trans is cold (haven't driven far)? How old are the trans and transfer fluids? Conventional or synthetic oils?

My trans used to grind and was hard to shift on my old British car (TR6) until I switched to synthetic trans oil.

 

Good idea.



I'll try that tonight.

This is what worked best for me.

Vehicle/ transmission was fairly warm at the time. Haven't tried it cold. Re fluids, transmission drain and refill was done a couple months ago. Have not done a flush. Couldn't tell you when the TC was done as I don't have my records at the moment. I do know that the vehicle was Toyota serviced at the recommended intervals. Otherwise conventional oils used. Will most likely switch everything to synthetic sometime this year.

 

In some auto trannys you get a bit of a "windmill" effect from all the spinning components. Placing the tranny in park will prevent the auto tranny output shaft from turning but then if the t-case gears aren't lined up to mesh you end up having to put it back in gear and repeat the process.

IMHO the best thing to do is throw the tranny in neutral at around 1 mph, let the vehicle decelerate to where it is about to stop, then give the t-case handle a quick, firm tug. Between the tranny being in neutral and the moving vehicle turning the t-case gears, you are assured that things will mesh without risk of any gears spinning too fast. The worst thing you can do is move the t-case handle slowly allowing the gears to grind before becoming fully meshed.

Cold gear oil will always aggravate gear grinding, even in trannys with synchronizers.

 

Yeah that seems to work the best for me too.

 

Putting the transmission into Park, then into Neutral works like a charm! No grinding going into 4L and back into 4H what-so-ever. Thanks guys!

 

Have you changed the gear oil lately? I had a similar problem in my 2nd gen & fresh lube helped. I used synthetic.
Paul

 

I've changed, but not flushed, the transmission fluid only. I'm going to do synthetic in the TC and the front/read diffs soon, though.

 

Hi,
I've been looking for information on my transfer case grind for weeks.
I have done a complete oil change in the gearbox, drained the transfer case, changed the transfer case but still these grind except when the oil is very hot.
And this subject informs me that I take too long to go from H4 to L4 and vice versa, as a result the secondary shaft starts to turn and this prevents the transfer case from shifting. THANKS!
My truck is a 2014 Toyota hilux, 3.0L diesel 171 HP, from France.
But I wonder if all hilux like mine have the gearbox secondary shaft that starts to turn when the gearbox and transfer case are in neutral