I just got back from taking the family out to Colorado for spring break. We live in Texas and don't have the inclines that we see when we go west for vacations. Getting up into the Rockies leaving Denver my Tacoma (3.4 v6) prefers it if I drop out of OD. Is climbing these steep grades harder on the engine or tranny? I try to be as gentle as possible but keeping up with traffic sometimes makes the motor work pretty good. I have fresh ATF and PP 5w30 in so fluids are all good.
mountain inclines?
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LOL! you flat-landers crack me up good!
I have challenged steep incline with 300lbs payload in my Suzuki 3cyl 1L M/T-5 spd over the course of a 26degree slope using 1st gear @5200rpm, and am I worried about it?
Q.
I have challenged steep incline with 300lbs payload in my Suzuki 3cyl 1L M/T-5 spd over the course of a 26degree slope using 1st gear @5200rpm, and am I worried about it?
Q.
Most owner's manuals suggest taking it out of OD when driving in mountainous terrain.
Kestas
Staff member
In the mountains I work the D/OD as needed. I'd hate to coast in D on those gentle inclines where you'd like to maximize your momentum and gas mileage just before coming up to another hill.
I see no problem leaving it in OD going up the inclines. The transmission does the thinking for you and picks the optimal gear for the driving conditions. The only time you drop it to D is when conditions are such that there is too much shifting back and forth and the transmission is "hunting" between the two gears.
I see no problem leaving it in OD going up the inclines. The transmission does the thinking for you and picks the optimal gear for the driving conditions. The only time you drop it to D is when conditions are such that there is too much shifting back and forth and the transmission is "hunting" between the two gears.
I agree with Kestas. So long as the tranny isn't hunting in and out of OD, its fine to leave it there. The tranny does the thinking and work that is needed, and will find D when needed and return to OD when acceptable. When it goes back and forth between the two repeatedly, then its time to drop out of OD. Hauling a trailer through western Iowa up and down the hills is one place where this scenario has come to mind.
Dropping out of OD also works for engine braking on those long downhill grades.
And yes, your tach starts to spend a lot of time at higher numbers than you are used to as a "flatlander".
(And for those who wonder why someone from Minnesota would know any of this, just know I am a Colorado State alumni and spend plenty of time in the Mountain West...)
Dropping out of OD also works for engine braking on those long downhill grades.
And yes, your tach starts to spend a lot of time at higher numbers than you are used to as a "flatlander".
(And for those who wonder why someone from Minnesota would know any of this, just know I am a Colorado State alumni and spend plenty of time in the Mountain West...)
The transmission doesn't always do the optimal thing. It can't predict hills. My TL will unlock the torque convertor and stay in 5th gear under heavy throttle, creating tons of heat in the trans. If I manually pull it down to 4th, the torque convertor locks due to less load on the engine and rpms are identical to 5th with the convertor unlocked, creating less load and less heat.
I would much rather pull a hill with the torque convertor locked in a lower gear than unlocked in a higher gear.
I would much rather pull a hill with the torque convertor locked in a lower gear than unlocked in a higher gear.
Originally Posted By: MNgopher
Dropping out of OD also works for engine braking on those long downhill grades.
And yes, your tach starts to spend a lot of time at higher numbers than you are used to as a "flatlander".
Sometimes I'll force the Camry's ATX into first gear to slow down. The thing with it is that it won't downshift to 1st unless the speed is below 50KM/H, which pushes the RPMs to a measly 4500. By putting the gear selector in L (1st), hydraulically, routes pressure to the first gear clutch, but the TCM keeps the 2nd solenoid open until the speed drops to 50km/h. Forget that, so I switch the ignition off with the lever in L at speeds upwards of 65km/h, that way with no power, the computer can't prevent the downshift and I can use all the engine braking from 5500 down
It might sound abusive, but it's not really, as long as it doesnt downshift into redline. People must be wondering, seeing the DRLs turn off and then on again
Dropping out of OD also works for engine braking on those long downhill grades.
And yes, your tach starts to spend a lot of time at higher numbers than you are used to as a "flatlander".
Sometimes I'll force the Camry's ATX into first gear to slow down. The thing with it is that it won't downshift to 1st unless the speed is below 50KM/H, which pushes the RPMs to a measly 4500. By putting the gear selector in L (1st), hydraulically, routes pressure to the first gear clutch, but the TCM keeps the 2nd solenoid open until the speed drops to 50km/h. Forget that, so I switch the ignition off with the lever in L at speeds upwards of 65km/h, that way with no power, the computer can't prevent the downshift and I can use all the engine braking from 5500 down
It might sound abusive, but it's not really, as long as it doesnt downshift into redline. People must be wondering, seeing the DRLs turn off and then on again
I drove my '06 Monte clear across I-70 and took some little detours including a drive up Pikes Peak while in Colorado. I punched it a few times climbing the grades on I-70, running it up to "redline" to pass or just for fun. Neither the transmission nor engine missed a beat, so I wouldn't worry about it.
I did find it interesting that it dialed back the redline shift RPM while at high altitude. Typically it shifts out of 2nd at about 6200, but while up around 10,000 feet and above I noticed it shifting up around 5600. A turbo probably would have helped up there.
I did find it interesting that it dialed back the redline shift RPM while at high altitude. Typically it shifts out of 2nd at about 6200, but while up around 10,000 feet and above I noticed it shifting up around 5600. A turbo probably would have helped up there.
Originally Posted By: Quest
LOL! you flat-landers crack me up good!
X2. I have hauled 80,000lbs of truck and Cement with a 300hp L-10 Cummins up a 16% grade a bunch of times.
1st gear and put it to the floor.
LOL! you flat-landers crack me up good!
X2. I have hauled 80,000lbs of truck and Cement with a 300hp L-10 Cummins up a 16% grade a bunch of times.
1st gear and put it to the floor.
If God wanted texans to have mountains he'd have given them their own. Level ground seems to challenge most of them.
Originally Posted By: BuickGN
The transmission doesn't always do the optimal thing. It can't predict hills. My TL will unlock the torque convertor and stay in 5th gear under heavy throttle, creating tons of heat in the trans. If I manually pull it down to 4th, the torque convertor locks due to less load on the engine and rpms are identical to 5th with the convertor unlocked, creating less load and less heat.
I would much rather pull a hill with the torque convertor locked in a lower gear than unlocked in a higher gear.
I agree!
I wish those who program the TCMs would think this way.
As you wrote, the grade logic on some ATs is stupid, is just unlocks the TCC but keeps it in top gear. Grade logic is supposed to be intelligent, so please shift down and keep the TCC engaged!
The transmission doesn't always do the optimal thing. It can't predict hills. My TL will unlock the torque convertor and stay in 5th gear under heavy throttle, creating tons of heat in the trans. If I manually pull it down to 4th, the torque convertor locks due to less load on the engine and rpms are identical to 5th with the convertor unlocked, creating less load and less heat.
I would much rather pull a hill with the torque convertor locked in a lower gear than unlocked in a higher gear.
I agree!
I wish those who program the TCMs would think this way.
As you wrote, the grade logic on some ATs is stupid, is just unlocks the TCC but keeps it in top gear. Grade logic is supposed to be intelligent, so please shift down and keep the TCC engaged!
Max---dude you have problems-If I were you, I'd think about spending some time in therapy, rather than internet message boards
Steve
Steve
Originally Posted By: steve20
Max---dude you have problems-If I were you, I'd think about spending some time in therapy, rather than internet message boards
Steve
Who is this guy---Dr--- Phil-?----
No, but seriously, thank you for the opinion no one asked for.
Max---dude you have problems-If I were you, I'd think about spending some time in therapy, rather than internet message boards
Steve
Who is this guy---Dr--- Phil-?----
No, but seriously, thank you for the opinion no one asked for.
Originally Posted By: Max_Wander
Originally Posted By: MNgopher
Dropping out of OD also works for engine braking on those long downhill grades.
And yes, your tach starts to spend a lot of time at higher numbers than you are used to as a "flatlander".
Sometimes I'll force the Camry's ATX into first gear to slow down. The thing with it is that it won't downshift to 1st unless the speed is below 50KM/H, which pushes the RPMs to a measly 4500. By putting the gear selector in L (1st), hydraulically, routes pressure to the first gear clutch, but the TCM keeps the 2nd solenoid open until the speed drops to 50km/h. Forget that, so I switch the ignition off with the lever in L at speeds upwards of 65km/h, that way with no power, the computer can't prevent the downshift and I can use all the engine braking from 5500 down It might sound abusive, but it's not really, as long as it doesnt downshift into redline. People must be wondering, seeing the DRLs turn off and then on again
I took this as a joke at first. Now I'm not sure. What are you trying to accomplish by downshifting at 5,500rpm? Save the brakes but kill the engine? You do realize the effective redline is lower when the engine is not under load, right? It's easier to hurt things from excessive rpm without a load on the engine.
Originally Posted By: MNgopher
Dropping out of OD also works for engine braking on those long downhill grades.
And yes, your tach starts to spend a lot of time at higher numbers than you are used to as a "flatlander".
Sometimes I'll force the Camry's ATX into first gear to slow down. The thing with it is that it won't downshift to 1st unless the speed is below 50KM/H, which pushes the RPMs to a measly 4500. By putting the gear selector in L (1st), hydraulically, routes pressure to the first gear clutch, but the TCM keeps the 2nd solenoid open until the speed drops to 50km/h. Forget that, so I switch the ignition off with the lever in L at speeds upwards of 65km/h, that way with no power, the computer can't prevent the downshift and I can use all the engine braking from 5500 down
It might sound abusive, but it's not really, as long as it doesnt downshift into redline. People must be wondering, seeing the DRLs turn off and then on again
I took this as a joke at first. Now I'm not sure. What are you trying to accomplish by downshifting at 5,500rpm? Save the brakes but kill the engine? You do realize the effective redline is lower when the engine is not under load, right? It's easier to hurt things from excessive rpm without a load on the engine.
No, it's not a joke!
The engine is fine!! It's a beast with over 320,000KM on it and runs as good as it's going to. Technically, there is a load on the engine, it's just inverse. The short and tall of it is, I do like to drive my ATX cars as manually as possible and the Toyota engineers were just way too [censored] about a lot of the thresholds in this car, ie the 1st gear downshift speed.
I've totally rationalized it and if I thought this was bad for engines, then the POS 5S-FE with it's abysmally short rods would be the last engine I'd downshift on. Camry brakes are terrible. Theyre mushy, underassited, non-linear and they fade from anything. Camry driving dynamics overall are horrible. Maybe there's an underlying psychological disdain for the vehicle somewhere subconsciously lol (maybe I do need that therapy
). Really though, theres nothing hurting that engine, the vacuum puts some load on the other side of the bearings, and actually pulls on the rings which only happens during engine braking, a condition rarely ever seen in ATX mated engines. If a rod pops out, it'll be my first one in the many engines I've made brutal demands on throughout my life. I tell ya though, front tires really show all the downshifting, rear tires have remained almost virginal. Rotated 3 days ago
Glanced at the pad linings, still meaty!
The engine is fine!! It's a beast with over 320,000KM on it and runs as good as it's going to. Technically, there is a load on the engine, it's just inverse. The short and tall of it is, I do like to drive my ATX cars as manually as possible and the Toyota engineers were just way too [censored] about a lot of the thresholds in this car, ie the 1st gear downshift speed.
I've totally rationalized it and if I thought this was bad for engines, then the POS 5S-FE with it's abysmally short rods would be the last engine I'd downshift on. Camry brakes are terrible. Theyre mushy, underassited, non-linear and they fade from anything. Camry driving dynamics overall are horrible. Maybe there's an underlying psychological disdain for the vehicle somewhere subconsciously lol (maybe I do need that therapy
Originally Posted By: Max_Wander
Glanced at the pad linings, still meaty!
I never could understand why some people are proud of the fact that they can make a $29 set of brake pads last longer by constantly downshifting and doing twice as much clutching as would otherwise be necessary or by, um...I guess downshifting an AT into 1st and running it at 5500 with the ignition off?
I'm happy to slam on the brakes and wear the pads out as quickly as possible. They're cheap and take about 20 minutes to replace, the same is not true for the clutch, the transmission or the engine.
Glanced at the pad linings, still meaty!
I never could understand why some people are proud of the fact that they can make a $29 set of brake pads last longer by constantly downshifting and doing twice as much clutching as would otherwise be necessary or by, um...I guess downshifting an AT into 1st and running it at 5500 with the ignition off?
I'm happy to slam on the brakes and wear the pads out as quickly as possible. They're cheap and take about 20 minutes to replace, the same is not true for the clutch, the transmission or the engine.
Originally Posted By: BuickGN
Originally Posted By: Max_Wander
Originally Posted By: MNgopher
Dropping out of OD also works for engine braking on those long downhill grades.
And yes, your tach starts to spend a lot of time at higher numbers than you are used to as a "flatlander".
Sometimes I'll force the Camry's ATX into first gear to slow down. The thing with it is that it won't downshift to 1st unless the speed is below 50KM/H, which pushes the RPMs to a measly 4500. By putting the gear selector in L (1st), hydraulically, routes pressure to the first gear clutch, but the TCM keeps the 2nd solenoid open until the speed drops to 50km/h. Forget that, so I switch the ignition off with the lever in L at speeds upwards of 65km/h, that way with no power, the computer can't prevent the downshift and I can use all the engine braking from 5500 down It might sound abusive, but it's not really, as long as it doesnt downshift into redline. People must be wondering, seeing the DRLs turn off and then on again
I took this as a joke at first. Now I'm not sure. What are you trying to accomplish by downshifting at 5,500rpm? Save the brakes but kill the engine? You do realize the effective redline is lower when the engine is not under load, right? It's easier to hurt things from excessive rpm without a load on the engine.
Shut the engine off, no power steering no power brakes, over heat the AT. Doesn't sound like a good idea. I'll never do it.
I'll anticipate ahead of time if possible what gear I need, with a MT its pretty easy, I'll take a decline in 2nd or 3rd gear, and tap the brakes when needed. If I'm going up and down hills with an AT, I'll use either drive or second, and if speed is building up too much use the brakes. I've been all over the US driving and haven't ruined a clutch, AT or smelled brake linings burning yet. Anticipate ahead of time what gear you think you'll need, upshifting because you're using too low a gear is very easy. Brakes are cheap, transmissions and clutches aren't.
Originally Posted By: Max_Wander
Originally Posted By: MNgopher
Dropping out of OD also works for engine braking on those long downhill grades.
And yes, your tach starts to spend a lot of time at higher numbers than you are used to as a "flatlander".
Sometimes I'll force the Camry's ATX into first gear to slow down. The thing with it is that it won't downshift to 1st unless the speed is below 50KM/H, which pushes the RPMs to a measly 4500. By putting the gear selector in L (1st), hydraulically, routes pressure to the first gear clutch, but the TCM keeps the 2nd solenoid open until the speed drops to 50km/h. Forget that, so I switch the ignition off with the lever in L at speeds upwards of 65km/h, that way with no power, the computer can't prevent the downshift and I can use all the engine braking from 5500 down
It might sound abusive, but it's not really, as long as it doesnt downshift into redline. People must be wondering, seeing the DRLs turn off and then on again
I took this as a joke at first. Now I'm not sure. What are you trying to accomplish by downshifting at 5,500rpm? Save the brakes but kill the engine? You do realize the effective redline is lower when the engine is not under load, right? It's easier to hurt things from excessive rpm without a load on the engine.
Shut the engine off, no power steering no power brakes, over heat the AT. Doesn't sound like a good idea. I'll never do it.
I'll anticipate ahead of time if possible what gear I need, with a MT its pretty easy, I'll take a decline in 2nd or 3rd gear, and tap the brakes when needed. If I'm going up and down hills with an AT, I'll use either drive or second, and if speed is building up too much use the brakes. I've been all over the US driving and haven't ruined a clutch, AT or smelled brake linings burning yet. Anticipate ahead of time what gear you think you'll need, upshifting because you're using too low a gear is very easy. Brakes are cheap, transmissions and clutches aren't.
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