I have a 1991 4Runner 6cyl 4X4 with 263,000 miles. Recently when traveling at highway speeds I noticed that the trans seems to be overheating. There is trans fluid sprayed on the back of the vehicle and fluid dripping from the transmission. The underside of the vehicle is wet with fluid too. It appears to be coming from the top of the transmission. Not sure if there are any warning lights on the dash to indicate trans overheating but I haven't noticed anything. The fluid level is still in the normal range so I am a bit perplexed. Is my transmission shot or (fingers crossed) is this something that may be a simple and inexpensive fix? Any help would be greatly appreciated.

 

sounds more like u have a bad seal somewhere but could be overheating, there should be a light on the dash to let u know if it is over heating, now the light might be bad.

 

Ugh, mine does this too. I hope you can figure something out. I can't. I've flushed my tranny fluid, run AutoRX thru the tranny beforehand. I found a cooler on the passenger frame rail that was all plugged up with oil and grime I degreased and pressure washed the other day. The lines run toward the back of the transfer case, so maybe that'll fix it. I can overheat running 70 down the freeway, and it's worse now that it's hot. I have factory 4.88s, 31s, and factory trans cooler.

edit: also sprays fluid out the tranny and gets all over the tailgate

 

If a trans is overfilled it will blow fluid out the vent at the top of the trans. You stated that the fluid level is ok, I assume you checked it when the trans was warm and the truck was in park at idle.
Could be a seal leaking but is hard to tell with fluid everywhere. My suggestion would be to clean at a car wash or however then run dye in the trans. Dye will help you locate the leak. From there it may or may not be an easy fix. Automatic tansmissions are not as terrifying as made out to be.

 

Maybe this is a stupid question, but how does transmission fluid get all over the back of the vehicle and on the tailgate? I'm no mechanic, but I do know where the transmission is. How does the fluid make it's way back there?

 

Fluid blows back due to the air pressure under and behind a vehicle. Very common for fluid to blow over exhausts, driveshafts, diffs when a bad leak is occuring.

 

To flow back, and then up on the backside of the vehicle? Dang, that must be one heck of a leak!

 

this might sound stupid, but has the vent been checked? if it's stopped up, the air has no where to go but out the dipstick!

 

A vacuum is actually created behind the vehicle. Air circulation causes the mist to whip up and cover.
Yea, must be a hell of a leak. Hard to believe his fluid level is ok.

 

At the risk of threadjacking, can't speak for OP. Mine only blows fluid on the tailgate and down the back of the undercarriage after the a/t temp warning light comes on and I have to continue to drive for a little bit. If I can pull over immediately, I do not get leakage anywhere. I have had to add a bit of fluid due to this happening several times, but always checked fluid level w/ truck plenty hot, running, and in park. I actually gave up for a year and just drove slower. Never overheats at 65ish, and torque conveter locks and unlocks correctly. I'm hoping my newly found (transfer case) cooler unplugging does the trick.