03 V8 4x4 Slow itself down going downhill fast?

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parks71

New member
I just bought an 03 V8 4x4 since I just moved to Colorado. I feel like I have to press the gas harder then a normal truck/car to make it go or it will just slow down faster than normal on me. The gas pedal is much harder to depress than my 2009 CX9.

I went way up into the mountains yesterday and on the way back I noticed I had to press the gas considerably to make it go downhill or I would just slow down. I would slow down from 65 to say 50 or 55 in seconds after letting off the gas going downhill on a 6% grade on I-70.

I know this truck is all time 4wd and thats almost what feels like is hanging up. The RPM's stay low, its not downshifting so I am assuming its the transmission or some sort or auto braking.

My other SUV, the CX9, the vehicle almost spirals out of control coming down the mountain and I am constantly hitting the brakes or downshifting.

Is this typical of the 4runner or is there something wrong? Thanks!
 
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The 4Runner does have grade-logic in the transmission. If you are going down a steep hill, it will downshift to increase engine braking. But you should be able to notice that downshifting.

Are any of your brakes dragging? Take it for a drive for 30+ minutes, including highway driving. Then pull over and put your hand on each of the wheels. The wheels should be cool to the touch. If they are hot, you have a brake that is dragging.
 
brake drag is a good one, I'll check that out today. Thank you for the suggestion! The only thing that doesnt make sense about brake drag is I got 16.7 mpg on my first tank of gas around town and that is by real calculation, not the computer which was wrong.
 
parks71 said:
I just bought an 03 V8 4x4 since I just moved to Colorado. I feel like I have to press the gas harder then a normal truck/car to make it go or it will just slow down faster than normal on me. The gas pedal is much harder to depress than my 2009 CX9.

I went way up into the mountains yesterday and on the way back I noticed I had to press the gas considerably to make it go downhill or I would just slow down. I would slow down from 65 to say 50 or 55 in seconds after letting off the gas going downhill on a 6% grade on I-70.

I know this truck is all time 4wd and thats almost what feels like is hanging up. The RPM's stay low, its not downshifting so I am assuming its the transmission or some sort or auto braking.

My other SUV, the CX9, the vehicle almost spirals out of control coming down the mountain and I am constantly hitting the brakes or downshifting.

Is this typical of the 4runner or is there something wrong? Thanks!
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Make sure your not in "overdrive"...If your auto transmission shifter is in "D", your good, if it is clicked over to the left, you may just be in a a lower gear.
 
Snesley Wipes said:
Ya that, I get those backwards sometimes thanks!
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FWIW the torque converter locks in 4th and 5th gear. Driving in 4 won't hurt a thing.


OP you say the RPM's stay low. This isn't some 4-banger that cruisers hums at >3k on the highway. When mine downshifts to aid braking it rarely goes above 2500RPM.

If the same thing happens in neutral something's up - try that first.
 
parks71 said:
I would slow down from 65 to say 50 or 55 in seconds after letting off the gas going downhill on a 6% grade on I-70.
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If the particular section you were on was actually 6% and there was no substantial head wind, what you described shouldn't come close to happening, at least it wouldn't in my '05.

There's a 13 mile section of road near me that is 6% overall and it's a pretty consistent grade (computed from multiple, separate GPS tracks). Starting from 50mph in 5th gear with no pedal, I will gain speed overall, sometimes hitting more than 75mph.
 
JB. said:
If the particular section you were on was actually 6% and there was no substantial head wind, what you described shouldn't come close to happening, at least it wouldn't in my '05.

There's a 13 mile section of road near me that is 6% overall and it's a pretty consistent grade (computed from multiple, separate GPS tracks). Starting from 50mph in 5th gear with no pedal, I will gain speed overall, sometimes hitting more than 75mph.
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strange, cause whenever I want to coast I usually throw it in neutral to keep the engine brake from activating
 
OK did some testing today and I dont think the brakes are hanging up but I'll be taking it to get my tires rotated this week and have them double check.

I do feel like its almost like an engine brake but it doesnt rev high or anything like my CX9 will do going down hill. It's just odd I have to give it gas to go down hill.

I was in some steeper hills today and it didnt really do it but I was at a much lower speed, maybe 25 and it would get away from me if I didnt brake or down shift. Maybe because I was going 75-80 downhill was the reason I had to gas it so much?

Another thing it does which might be perfectly normal, I dont know but when I was climbing the mountains and had to give it gas and change gears I could smell something but only with the back window down. I am thinking it was just the exhaust due to having to give it gas and being at high speed. ANyone else have this happen?

Does this truck have some sort of engine braking. Berretta sounds like he has the same issue in the hills so is this normal? THanks everyone.
 
1) It has grade logic in the transmission. If you are going downhill, it will downshift the transmission to increase engine braking.

2) The 4Runner has all the aerodynamics of a brick. At 75 mph, there is a huge amount of aerodynamic drag. Yes, it takes a lot of gas to keep it moving at that speed.
 
Doesn't dowhill grade logic require a touch of the brake pedal? OP said he just let off the gas.
 
JB. said:
Doesn't dowhill grade logic require a touch of the brake pedal? OP said he just let off the gas.
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That was my understanding and experience. Mine only downshifts when I am over a certain speed, going down a certain grade, and then tap the brakes. It will disengage when I press on the accelerator. I've never had it go on when on the freeway, though. I've only noticed it at speeds between 30-50 mph.
 
I just did some research on downhill grade logic and people say it makes their vehicle have a difficult time coasting and thats exactly what the 4runner does. I think this is what is going on and it appears perfectly normal.
 
M1911 said:
1) It has grade logic in the transmission. If you are going downhill, it will downshift the transmission to increase engine braking.

2) The 4Runner has all the aerodynamics of a brick. At 75 mph, there is a huge amount of aerodynamic drag. Yes, it takes a lot of gas to keep it moving at that speed.
Click to expand...

If you have no brake issues then this is your answer.
 
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