Altitude

[mistersnowman97]

op. i would do a trans fluid exchange. stay in proper gear to be in vehicles powerband. i find mine around 3-4k 3500 is pretty good spot

sounds good. seems like the most plausible solution. one of the guys earlier said it could be slipping... That's just not true. the thing runs fine all day everywhere else for long trips.

The times that it got hot, however, was on hot summer days, so hopefully the snow will keep it cool

 

[AddictedOffroad]

A/T temp light doesn't come on until you hit 300* in these vehicles. At that point, you've already smoked your tranny. Which is why its happening a lot more now.

OD Off should be run at all time on grades. It locks the torque converter and will keep the tranny from overheating. I would highly recommend a tranny temp gauges and an aftermarket cooler up front. This will help, but its not idiot proof. Don't let temps get above 230* on your tranny as things start to breakdown after that point.

I am curious if when you drained and refilled your tranny, you didn't take into account the Tcase being shared. I bet you are low on fluid which is why it hasn't overflowed when its boiling at 300*. Its also what is allowing it to overheat faster.

 

[AddictedOffroad]

between the t-case, and transmission?

no, I don't think they are shared. there should be a seal between the two. if they in fact ARE shared, that will be the first time ive heard of that.

They are most definitely shared.

 

[AddictedOffroad]

one of the guys earlier said it could be slipping... That's just not true. the thing runs fine all day everywhere else for long trips.
:

It most definitely is slipping the torque converter. Because that is what its designed to do to create a little more power. Its the only possible way for that light to ever come on.

In OD when you are cruising down the freeway on flat ground, tap your foot onto the brake slightly and you will see the rpms raise up a few hundred rpms. That is the torque converter unlocking since its supposed to when you brake. That is allowing the torque converter to slip. It does the same thing under heavy load. That in turn causes heat. This is how autos work.

And, even though you think the tranny is fine, there is a reason this is happening. And, it could have been avoided by knowing how to drive an A/T and simply reading an owners manual.

 

[KidVermicious]

OD Off should be run at all time on grades. It locks the torque converter and will keep the tranny from overheating.

Wait, what? I thought the torque converter didn't lock unless you were in OD.

 

[AddictedOffroad]

Wait, what? I thought the torque converter didn't lock unless you were in OD.

It will lock and unlock in OD. Under heavy load it unlocks. Which in a 3.0L auto is almost all the time on grades. OD off will lock the torque converter in 3rd gear. That is why they tell you not to tow in OD, because it will be running most of the time with the torque converter unlocked. Building heat.

All A340 transmissions work this way. I've owned numerous ones in all different models. 1st gens, 2nd gens, 3rd gens......On my 2000 4runner, I ran a dedicated tranny cooler and bypassed the radiator. Then, I ran a Scan Gauge II with the Xcommand gauge setup for the A/T temp. It gave me real world tranny temps. That rig was supercharged, SAS'd and on 37s. I would tow a rather big pop-up camper with it all throughout Colorado in the mountains. It was a heavy 4runner weighing over 5000lbs.

When the torque converter would unlock in OD, I would see a temp increase of a degree per second. I would run it up to about 215, then hit the OD off button. At that instant, it would start to drop a degree per second in temp. The tranny would routinely run around 180* during the summer on the flats when towing. Even a 2-3% grade would unlock the torque converter. You would know because of a 300rpm increase in OD.

 

[KidVermicious]

It will lock and unlock in OD. Under heavy load it unlocks. Which in a 3.0L auto is almost all the time on grades. OD off will lock the torque converter in 3rd gear.

Appreciate the education, thanks!

 

[mistersnowman97]

I hate automatic tranny's. Always have always will.

 

[ToyoTech]

todays automatics are the way of the future and than there is CVT. they are not what they used to be. shifts are faster and perfect everytime.

 

[DC runner]

I agree. I used to be a manual only fellow, and now I am a changed man.

Today's autos are amazing. You get increased low end torque and towing due to the mechanical advantage of the non-compressive hydraulic fluid in the torque converter.

Off road, a auto in 4lo gives you that insane feather touch and control that is necessary in places where you are shaving a razors edge between literally a rock and a hard place. I don't have to be worrying about my clutch and gas and that stupid tree.

They are as reliable as manuals and super smooth. I have a 1994 Nissan King Cab v6 with a manual as my project truck and I own a 4th gen 4runner, v8. The 4runner is an auto, as they all are, and it hands down beats the nissan in every way.

Manuals are manuals, but today's autos really are superior.

 

[mistersnowman97]

I definitly agree that today's are far superior and are far more developed. I just can't stand the one in my runner. 4 gears just doesn't do a lot for me xD oh well. i just gotta suck it up I guess.

 

[ToyoTech]

high end rock crawlers have already learn that auto is the way to go. they been using auto for sometime now

 

[SV_Dude]

My wife has a nissan juke with the cvt transmission and I am not fond of it at all. When the vehicle is already moving it is nice and allows the engine to stay in its power band. But, when at a stop the car is extremely sluggish until you get to a few miles per hour. Now a few mph may not seem like a big deal to get up to but I almost have to floor the gas pedal to get the car moving. If I'm on an incline then I have to literally floor it in order to get moving. Once the car has some momentum I have to let off the gas pedal because then it wants to take off.

 

[ToyoTech]

should have gotten the juke turbo?? lol too small of an engine for the vehicle?

 

[SV_Dude]

should have gotten the juke turbo?? lol too small of an engine for the vehicle?

It has the turbo and it has some pep once the turbo spools up.

 

[ToyoTech]

It has the turbo and it has some pep once the turbo spools up.

so what does the boost button do?

 

[SV_Dude]

so what does the boost button do?

You talking about the driving modes? It has a little more pep when in boost/sport mode but the off the line power is still extremely sluggish.

 

[mistersnowman97]

my mom has an infinity crossover. that thing is useless off the pavement really. (unless you want to ruin it) but it sure is fun on the road. very quick too. the auto in that I don't mind.

 

[giro]

Looks like you found your likely answer, but since I live in Tahoe I wanted to let you know that the old 4runners do fine up here without any modifications. There are some hills that are tough (267 from Truckee to Kings Beach seems to be the worst), but my 92 V6 MT was my daily driver up over 431 to Reno for a couple years, which tops out at 8900'. I'd have to downshift, but I could hold 55-60 going up that grade without pushing it too much.

OTOH, the 98 v6 AT I had for a while had a bit more power and did that climb easier. And the 92 doesn't have the power going up to pass anyone, unless it's a semi doing 30.

Enjoy your trip. Our house at 7500' is supposed to get 5-10" over the next 2 days, but that drops off significantly when you drop down closer to the lake.