The transfer box require 75W oil.

But this should not effect the gearbox shifting. As you don’t mention that you did a drain and fill of the ATF perhaps the two events are actually unrelated?

 

Never touched the transmission fluid. Only the transfer case, drain and fill. The problem seems to happen after a stop or a sharp turn. After I come to a dead stop it takes a couple of seconds for the FJ to lurch forward as if 1st gear had just engaged.

 

Double check that you got the air cleaner on right.

 

Checking it now

 

Check the level of your tranny fluid. Sounds like when the oil splashes around your pickup isn't in the oil and so you lose pressure and the transmission can't shift.

 

Air filter is good to go. Where can I check the tranny fluid on this FJ ? I know the differentials and transfer case access but not this "sealed" transmission

 

Almost certainly you accidentally drained the transmission oil pan instead of the transfer case, and now the transmission is grossly low on ATF.

Accidentally draining the transmission pan is the ONLY thing that will cause the transmission to shift the way you describe. Happening after a stop or a sharp turn absolutely confirms it, as the ATF level in the pan is so low that the fluid sloshes away from the pump pickup tube and then line pressure instantly drops and the clutches start slipping.

STOP DRIVING IMMEDIATELY !!!!

If you continue to drive with the transmission 3+ quarts low on ATF, and the transmission slips in any gear, you will burn up the clutch packs almost immediately and destroy the transmission.

Was this the first time you serviced the transfer case gear oil?

 

Yeah... my money is on accidentally draining the transmission as well (not a rare occurrence unfortunately).

Check your engine oil level and you will be able to easily verify if you didn't drain it... AND added oil to it. It may be grossly overfilled now (as well as the transmission being low now).

 

I think he drained the AT pan and added an extra quart of gear oil to the transfer case.

This will be a little harder to confirm than if he added another 6 quarts of oil to the engine. He's going to have to drain the transfer case and see if 2.2 quarts come out.

Then, take the time to PROPERLY refill the transmission to the correct level using WS ATF.

There was at least one prior case on this forum where someone drained the transmission pan, and added another 6 quarts of engine oil to the engine sump. The transmission problem symptoms were identical.

 

I think he drained the AT pan and added an extra quart of gear oil to the transfer case.

It is very difficult to overfill the transfer case if you use the fill plug. The correct level is when the oil runs out the fill plug hole.
It sure sounds like the automatic transmission pan was drained but probably when trying to drain the engine oil. That is easier to mix up. The transfer case drain and fill plugs are pretty straight forward and not easy to confuse with anything else.

 

What was the color of the oil when the transfer case was drained? Reddish?

 

Thank you for your replies. In regards to the transfer case, there are only two plugs. One on the lower left for drain and one on upper right for fill. I loosened the fill plug and drained the crankcase. I refilled roughy 1.5 quarts of 75W-90 synthetic gear oil.I may found the problem. I neglected to put the gasket back on the fill plug. Looking into it now.

 

But what about the automatic transmission shifting problems that suddenly appeared immediately after you attempted to change lubricants in the engine and transfer case?

The transmission problems you described can only be caused by an extremely low ATF level.

What oil level did you find on the engine dipstick?

 

That’s a lot of funny shifting for a missing gasket on your transfer case, likely unrelated but let us know!

 

Is it my meds, or is this thread a bit wonky?

 

A few years ago there was a seemingly identical incident ... FJ owner was attempting his own preventive maintenance for the first time, accidentally drained the AT pan instead of the engine pan, added another 6 quarts of oil to the engine, fired it up and attempted to drive away.

His AT mis-shifting symptoms were absolutely identical to what the OP in this thread described.

He did come clean and admit what had happened.

 

You a we're correct upon triple checking. I see that I drained the automatic transmission pan. I have now drained the correct oil pan and changed filter (again). Found the fill plug for ATF WS and added almost 4 quarts until that red fluid started to leak out of the fill check plug. Test drove,, zero issues.. FJ is back in action. You folks are super helpful. Thanks again!

 

When adding ATF and verifying fluid level via the overflow port, you did make sure that the vehicle was level, the ATF was at operating temperature, and the engine was running, correct?

Simply adding cold ATF to transmission with the engine off until it runs out the check plug will NOT give the correct fluid level.

If ATF is not at operating temperature, correct level cannot be set ... Toyota is very specific about this.

If engine is not running when you check the level, ATF will have drained back into the pan from the transmission cooler and show an incorrectly high level at the check plug, and when the engine is started and ATF fills all the lines, the fluid will once again be lower than it is supposed to be.

 

The engine was choking on 12 qts of oil and the tranny pan was dry!

 

Oh well, **** happens.