Transmission woes
 

Hey guys, I have a 4 speed automatic A340H in a V6 1999 4Runner that is acting up. Lately it’s been relatively cold. About 25 at night and 35-40 during the day. Well when I start driving after the truck has been sitting cold, I put it in drive and press the gas pedal. RPMs go up but the truck is not moving. If it’s completely flat or down an incline it will creep forward slowly for about 30 feet, progressively getting more and more power to the wheels. After 30 feet it will drive normally. Fluid is sparkling clean and levels are correct. I’ve drained and refilled 4qts of Mobil 1 and nothing changed. What could it be?

Could it be that your rear drums are stuck? I've read here how seals can leak and gum up your rear drums. It may not be your tranny but I'm no expert.

All wheels spin freely I'm sure as I like to push it around in neutral if I need to move it a little without starting it up cold. :D I can mash the pedal pretty good and still won't move. Its definitely not drag anywhere. Oddness!

Only some guesses
 

Only ideas:
Torque converter
Clutch pack(s)
Linear solenoid

BTW, how many miles are on this 4runner?

There is alot more fluid in there than just what is in the pan (about 4-5 times more) but if the fluid is relatively clean and doesn't smell burnt, I doubt that is the issue. My next guess is that you may have a bad/stuck solenoid in the tranny which is forcing you to start out in a high gear, but then it usually won't drive normally right away. Try this, next time it does that, manually put it into second gear and see if it takes off better....if so it probably is a solenoid. Another thing is that the filter screen may be clogged with debris so you might want to pull the pan and clean it (can be reused). The problem could be in the converter, clutch packs, etc, but that type of work is best left to a pro.

do you feel it (or hear) go into gear? what about reverse?

i would try R to D to R to D. sounds like something is not engaging in the cold.
front pump?
high mileage - filter/screen clogged?

100k miles. Reverse always works fine as I always have to backup before driving. Feels like it goes into gear. No unusual sounds or feel or anything like that. I of course tried putting it in 2nd gear, as I certainly wasn't moving in D, and then 1st. Nothing changed. I just put it in 4L, drive about 20 feet, and then back into D, and then it works perfectly fine.

It doesn't happen every day it's cold either. But it does only happen when it's cold.

I have a similar problem, but on 4x4 mode. I would have to gas pretty hard for it to move between 0-15 mph. above that seems normal. Mine's also a 99. we have normal weather here, so that's not a factor.

That is strange indeed....I'm going to have to ponder that one a bit.

In the meantime you might try the other items I mentioned to see if that helped at all (clean the trans filter and do a fluid flush).

hey you should check out my post i had the same exact problem and i took it to toyota and they told me it was the rear seals and what happens is the fluid leaks out all over the rear brakes and they get stuck. I got all the rear seals and rear brakes replaced and everything was fixed.