2003 V8 4WD Transmission does not want to shift down hill

[balong48]

I have a 2003 4Runner Limited V8 with the 4WD. Recently, the transmission has started to not want to shift while going down hills. If I am going down a ramp in a parking garage I can press the gas pedal and watch the RPMs go up to about 2500 and it still won't shift into 2nd. I have to press the gas harder if I want it to shift. My first thought was that it could be just acting weird when the transmission is cold, but I have recently had two accounts where the car has warmed up and was running for at least thirty minutes when it happened.

The first time it happened I had turned the corner at an intersection and proceeded to accelerate on level ground, then I hit the downhill (which I needed to continue accelerating to maintain speed) and the transmission would not shift into the next gear and the RPMs went just over 3000. The transmission finally shifted once I got over the hill. There I believe it was stuck between 3rd and 4th gear, maybe 4th and 5th.

Then just yesterday I was stopped on a downhill at a stoplight. Light turned green and I give it gas. It accelerated but I was unable to keep up with the cars in front of me and they have pulled away. Meanwhile I felt like I had no power and the RPMs headed up to about 2500. I finally rounded the corner and it went into 2nd and shifted from there.

Has anyone else experienced this? I've checked the fluid level and it appears to be fine, the fluid looks fine, and smells fine. I have no lights on the dash either.

Thanks

 

[Walkenvol]

I recently purchase the same '03 V-8 4WD and noticed the same but I thought it was designed to do that. There's a button labeled DAC on the console between the front seats that appears to turn this feature on and off - maybe yours has always been disengaged and you've recently turned in on?

 

[balong48]

I recently purchase the same '03 V-8 4WD and noticed the same but I thought it was designed to do that. There's a button labeled DAC on the console between the front seats that appears to turn this feature on and off - maybe yours has always been disengaged and you've recently turned in on?

I've never used DAC and am not sure how it works but I assume it has to do more with the brakes. Plus I would see the indicator on the dashboard. It's a good thought though but after some reading DAC can apparently only be used in 4Lo and I am most definitely not driving in 4Lo all the time hahaha

 

[m85476585]

It's not DAC.

I've noticed that if the engine is cold (room temp or below, not necessarily winter), it shifts weird and has low power even at higher than normal RPM. This happens most of the times I leave my house. I'll be slowly accelerating on my street, and it's still in first at 2,500 RPM. When I go to pull out on the main street it often feels sluggish. Once it warms up, about a minute, it's normal. This might be the secondary air pump, but it lasts more than 30 seconds or continues after I hear the secondary air pump go off, so maybe not. And I don't think the OP's 2003 has a secondary air pump. It might be some other emissions-related programming in the engine that runs it different when it's first starting.

The transmission has "intelligence" ("ECT-i") that holds gears depending on the load it senses. If you are going up a hill, it will hold low gears longer. If you are going down a hill and lightly press the brakes for a few seconds, it will downshift a gear to maintain your speed. It also applies when you are towing a trailer since it senses the difference between the actual acceleration of the vehicle and what it expects. There is no way to adjust it or turn it off.

 

[balong48]

It's not DAC.

I've noticed that if the engine is cold (room temp or below, not necessarily winter), it shifts weird and has low power even at higher than normal RPM. This happens most of the times I leave my house. I'll be slowly accelerating on my street, and it's still in first at 2,500 RPM. When I go to pull out on the main street it often feels sluggish. Once it warms up, about a minute, it's normal. This might be the secondary air pump, but it lasts more than 30 seconds or continues after I hear the secondary air pump go off, so maybe not. And I don't think the OP's 2003 has a secondary air pump. It might be some other emissions-related programming in the engine that runs it different when it's first starting.

The transmission has "intelligence" ("ECT-i") that holds gears depending on the load it senses. If you are going up a hill, it will hold low gears longer. If you are going down a hill and lightly press the brakes for a few seconds, it will downshift a gear to maintain your speed. It also applies when you are towing a trailer since it senses the difference between the actual acceleration of the vehicle and what it expects. There is no way to adjust it or turn it off.

Right, I've experienced the engine braking while going downhill and it's very useful. However, the engine not being warm was my first theory but it's happened twice when the engine has been warmed for at least 30min. This is definitely not engine braking though as I am not trying to slow down, I am trying to continue accelerating.

EDIT: Unless, the software is confused and is trying to engine brake when I don't want it to

 

[Fred Ritchie]

Experienced similar problem when I bought my '04 SR-5, barely tap brakes going downhill and downshift was so hard that it would throw you forward into the seatbelt and would not continue at established speed when releasing brake, I had to touch gas to get truck to roll freely. I was told this is the design and is not broken. Seemed to me that if the truck decided that its choice of gear was better than mine it would have gone back to lower gear after I touched gas and came off again, if its gearing selection was right it should have returned there on its own until l bottom of hill was reached. Took truck to dealer and they wiped computer and told me to drive around for 30 minutes so computer could, "learn my driving style". Tech commented that this was one of the most common services he performed on used 4Runners, apparently vehicle adapts to one driver's habits. Strange. Downshifts are now less aggressive and I have gotten a bit used to this feature. I personally think it stinks, especially on two wheel drive versions used mostly on streets and roads like normal passenger cars. I could understand such a feature for aggressive off roading but on the highway its a pain in the butt. Nice ride but over-engineered!

 

[balong48]

Experienced similar problem when I bought my '04 SR-5, barely tap brakes going downhill and downshift was so hard that it would throw you forward into the seatbelt and would not continue at established speed when releasing brake, I had to touch gas to get truck to roll freely. I was told this is the design and is not broken. Seemed to me that if the truck decided that its choice of gear was better than mine it would have gone back to lower gear after I touched gas and came off again, if its gearing selection was right it should have returned there on its own until l bottom of hill was reached. Took truck to dealer and they wiped computer and told me to drive around for 30 minutes so computer could, "learn my driving style". Tech commented that this was one of the most common services he performed on used 4Runners, apparently vehicle adapts to one driver's habits. Strange. Downshifts are now less aggressive and I have gotten a bit used to this feature. I personally think it stinks, especially on two wheel drive versions used mostly on streets and roads like normal passenger cars. I could understand such a feature for aggressive off roading but on the highway its a pain in the butt. Nice ride but over-engineered!

That would be engine braking, which is great for towing things. What I am experiencing is not engine braking, rather the transmission not wanting to upshift while I am accelerating down a hill. I have not touched the brakes at all. Did it cost anything to get the computer wiped?

 

[m85476585]

Is it the same as disconnecting the battery for 15 minutes?

 

[KingPrat]

That would be engine braking, which is great for towing things. What I am experiencing is not engine braking, rather the transmission not wanting to upshift while I am accelerating down a hill. I have not touched the brakes at all. Did it cost anything to get the computer wiped?

Regardless of whether you've touched the brakes or not, the transmission will do this if you're accelerating downhill as well. It is programmed into the ECU. There's a sensor (I believe near the gas tank) that senses if you're heading up/downhill.

You'll get used to it. I liked it because it helps save your brakes if you're on a long downhill.

 

[balong48]

Regardless of whether you've touched the brakes or not, the transmission will do this if you're accelerating downhill as well. It is programmed into the ECU. There's a sensor (I believe near the gas tank) that senses if you're heading up/downhill.

You'll get used to it. I liked it because it helps save your brakes if you're on a long downhill.

Odd feature to have... It makes you lose power when you need it. I was at an intersection trying to get through after being stopped on a hill and couldn't keep up with the cars in front of me because of it. If this is a feature I don't think I've ever noticed it before due to where I live being relatively flat. Now that I'm my car is with me at college it's more hilly here than it is back home. It just seems like an odd feature to have on especially during acceleration.

 

[KingPrat]

Odd feature to have... It makes you lose power when you need it. I was at an intersection trying to get through after being stopped on a hill and couldn't keep up with the cars in front of me because of it. If this is a feature I don't think I've ever noticed it before due to where I live being relatively flat. Now that I'm my car is with me at college it's more hilly here than it is back home. It just seems like an odd feature to have on especially during acceleration.

Odd that you're not able to keep up. I was able to get mine up to 55 and be ok, would just hold it in 4th gear. Would hold shifts longer on the way there, but never keep me from getting up to speed. Perhaps an ECU reset would be a good move, as mentioned above.