Mountain And Snow

[breckbound]

Does anyone have experience with the AWD RX400h in mountain and snow conditions? Does the AWD function as well as traditional AWD? Does the Break function work well to control vehicle speed on downgrades and switchbacks, where 10mph is the desired speed, and minimizing use of regular breaks is the goal?

[wwest]

Does anyone have experience with the AWD RX400h in mountain and snow conditions? Does the AWD function as well as traditional AWD? Does the Break function work well to control vehicle speed on downgrades and switchbacks, where 10mph is the desired speed, and minimizing use of regular breaks is the goal?

Traditional AWD...??

No such animal...so many variations it's hard to keep track.

More than adequate AWD would be the system in the BMW X3.

Satisfactory would be the Acura RDX SH-AWD system.

Dead last, or very close thereby, would be any RX, HL, or Sienna AWD system.

[Rx330driver]

lol...in other words, toyota makes bad awd systems for their so called sport cross vehicles. from what i hear ^^ at least. hah

[mrc88dal]

I have an RX400h AWD and live in snowy/mountainous NH so I have direct experience with the car in the type of conditions you're asking about. First of all, you must put snow tires on the vehicle! I use Bridgestone Blizzaks on dedicated rims (Tirerack) and love them. With snow tires on the 400, the car performs superbly. I've routinely plowed through drifts and standing snow of +12" and have had no problems. I've been up fairly steep grades and again no problems. The AWD RX operates predominately in FWD mode but the rear wheels kick in seamlessly when needed. As always, driver technique goes a long way in the snow regardless of the car's drive system. Having used the 400 routinely in the conditions you're asking about, I can find no reason not to recommend it. The "B" function will slow the car on grades but will not hold a set speed even on moderate grades. The car will gain speed on grades even in "B" mode so braking will be required.

My previous car was a 4WD Toyota Sequoia which was a great snow performer so I was a bit apprehensive about switching to the RX AWD and scoured the boards like you're doing for real world experience. This winter alleviated my fears about the 400's snow performance. Unless you're going to be in extremely deep snow on unimproved roads, I think the 400 will be just fine. There's an expanded discussion on this topic, on this forum, titled "Rx400h - Awd (2007)"

[Jim Nazium]

There is no substitution for four full blown winter tires. Trust me. I live in MTL and have a country place up North (about 1.3hrs drive).

I have had a few types of AWD, 4WD vehicles. The real element or benefactor has always been the tires. If all things being equal, the 400h is capable of tackling any of the slippery winter conditions. Is the ultimate urban assault vehicle? Perhaps, given all the other benefits. But if you trying to compare the 400h to a full blown Range Rover or Jeep GCL w/ Quadradrive etc... with four full blown winter tires and you throw in offroading, then no contest the 400h is easily over matched by the latter.

Cheers,

MadloR

[wwest]

I have an RX400h AWD and live in snowy/mountainous NH so I have direct experience with the car in the type of conditions you're asking about. First of all, you must put snow tires on the vehicle! I use Bridgestone Blizzaks on dedicated rims (Tirerack) and love them. With snow tires on the 400, the car performs superbly. I've routinely plowed through drifts and standing snow of +12" and have had no problems. I've been up fairly steep grades and again no problems. The AWD RX operates predominately in FWD mode but the rear wheels kick in seamlessly when needed. As always, driver technique goes a long way in the snow regardless of the car's drive system. Having used the 400 routinely in the conditions you're asking about, I can find no reason not to recommend it. The "B" function will slow the car on grades but will not hold a set speed even on moderate grades. The car will gain speed on grades even in "B" mode so breaking will be required.

My previous car was a 4WD Toyota Sequoia which was a great snow performer so I was a bit apprehensive about switching to the RX AWD and scoured the boards like you're doing for real world experience. This winter alleviated my fears about the 400's snow performance. Unless you're going to be in extremely deep snow on unimproved roads, I think the 400 will be just fine. There's an expanded discussion on this topic, on this forum, titled "Rx400h - Awd (2007)"

"....routinely plowed through drifts and standing snow......"

Gee, I often did that just for fun back in MT in the sixties in my 63 T-bird.

Momentum is EVERYTHING.

What's it like to initially get up and going on an icy or packed snow roadbed, especially on an incline, when that traffic light changes to green, is the REAL question.

There are two notes of caution regarding the RXh AWD system.

1. You cannot fit tire chains to the rear wheels due to extremely tight tire/suspension clearance. So, as your owners manual will indicate, tire chains can ONLY be used on the front. Your owners manual will also state that higher roadbed traction on the front vs the rear can easily lead to loss of control and is to be avoided.

Tire chains, studs, or winter traction tires only on the front are in fact a recipe for disaster.

2. Since it is so serverely front torque biased the VDIM (VSC/Trac) will be extremely QUICK to dethrottle the engine upon even the slightest indication (so slight you may not have even noticed) of front wheelspin/slip.

The '08 RX will have the ability to disable Trac "first" and then additionally, in sequence, VSC, but I don't know about the RXh as it is much more serverely front torque biased over the RX. TC, Traction Control, is so agressive at dethrottling the engine upon any wheelslip/spin that many owners have found it virtually impossible to get these vehicles moving forward initially in adverse roadbed conditions. And spinning the wheels or rocking back and forth to get unstuck, IMPOSSIBLE!

This is opposed to VSC/Trac (or equivalent) on a rear torque biased AWD vehicle, such as the X3, wherein wheelspin/slip is not such as serious matter since at least some of the roadbed traction at the front is still reserved for maintaining directional control.

[mrc88dal]

What's it like to initially get up and going on an icy or packed snow roadbed, especially on an incline, when that traffic light changes to green, is the REAL question.

No problem. I actually own the car and routinely drive in those conditions.

[Colo Springs RX400h]

breckbound,

wwest is always negative on the 400h AWD capability and its ability in snow. However, if you look at the cars he owns, he doesn't own a 400h. I do own a 400h and live in Colorado Springs where we had a lot of snow this year. The 400h did great and went through some intersections where some other 4WD SUV's were stuck. If you are going to be going off road in deep snow, I'd get something else. But if you will be driving on paved roads in snow, you'll get much better mileage and a much better ride with the 400h verses other 4WD's.

If you use the search function, you'll see several other threads about this same topic, some of which I responded in more detail.

[Rx330driver]

its all about the tires. the system doesnt really matter.

[silvercorvette]

its all about the tires. the system doesnt really matter.

I disagree, it is all about the drive. some drivers can do better with 2 wheel drive and regular tires than other drivers can do with 4 wheel with snow tires. Some drivers idea of getting un-stuck in snow is to floor it while others rock themselves out.

[Rx330driver]

I disagree, it is all about the drive. some drivers can do better with 2 wheel drive and regular tires than other drivers can do with 4 wheel with snow tires. Some drivers idea of getting un-stuck in snow is to floor it while others rock themselves out.

i guess, but you hear stories all the time about 2wd cars being brilliant in the snow with just snow tires. two extra tires that have power is just an advantage.

[wwest]

breckbound,

wwest is always negative on the 400h AWD capability and its ability in snow. However, if you look at the cars he owns, he doesn't own a 400h. I do own a 400h and live in Colorado Springs where we had a lot of snow this year. The 400h did great and went through some intersections where some other 4WD SUV's were stuck. If you are going to be going off road in deep snow, I'd get something else. But if you will be driving on paved roads in snow, you'll get much better mileage and a much better ride with the 400h verses other 4WD's.

If you use the search function, you'll see several other threads about this same topic, some of which I responded in more detail.

While it's true that I don't own an RXh I do own a 2001 AWD RX300.

I use summer tires all year around but always have chains on board, two sets during the winter season.

My RX has 1.5" wheel spacers all around so I can use rear chains first and then add the fronts if conditions warrant.

I have very little doubt that the RXh has better AWD capability than my own AWD RX (excluding the mods), but I still say the RXh shouldn't be trusted as opposed to something like the BMW X3 or Acura RDX.

If the RXh F/R torque ratio were reversed I would probably own one today even though the RXh hybrid design, unlike our Prius, is more about POWER than FE.

[silvercorvette]

I disagree, it is all about the drive. some drivers can do better with 2 wheel drive and regular tires than other drivers can do with 4 wheel with snow tires. Some drivers idea of getting un-stuck in snow is to floor it while others rock themselves out.

i guess, but you hear stories all the time about 2wd cars being brilliant in the snow with just snow tires. two extra tires that have power is just an advantage.

My point is, and I have done this myself, you can have a driver get hopelessly stuck in the snow and another driver can get into that car and drive it out of whatever it is stuck in. I am a retired cop and have driven 2 wheel drive police cars through some deep stuff with out chains. I have come upon drivers stuck in snow who thought they would need a wrecker to get out. I got into their car and got the car un-stuck in a matter of minutes. Some people will get stuck in 4 wheel drive vehicles with snow tires because they just don't know how to drive. I was a cop for 20 years and from my experience people get stuck because they are poor drivers. And when poor drivers get stuck they usually blame the car. 4 wheel drive is helpful in snow but the skill of the drive is most important.

I am not saying 4WD isn't helpful because I have owned 4WD vehicles for almost 30 years, they do give you an edge but you can have 2 different drivers in the same vehicles with the same equipment and one will get stuck while the other won't. There may be a situation where both drivers get stuck but the main factor is the driver.

[SOMEONE ELSE'S GOT MY NAME]

We run (in the winter) front and back studs in the Flathead valley, MT. Got 'em at "Big-O". Good price and free mounting when we take 'em on and off each season. It's primarily my wife's car. She's always done fine in it. She had a drunk cross the highway right in front of her, late one midnight and was able to react on ice very well. I on the other hand ... did a 90 degree turn on ice, a litle too fast, and ended loosing it, plowing accross 3 feet of snow of our neighbor's yard ... and by keeping up the forward momentum I managed to mojo back onto the road, no worse for wear. Between the 2 of us (hard to believe after saying all that) believe it or not, I'm the one with more ice / snow driving experience.

[Jim Nazium]

its all about the tires. the system doesnt really matter.

It is AMAZING the technology found in todays modern "full" blown snow tires (not the M&S insignia found on four season tires).

1. Snow tires are designed with deep threads to counter deep snow and slush prior to any of the snow clearing trucks/equipment have been deployed.

2. The tire compound is designed to remain plyable in extremely cold -30F plus and yet still retain the flexibility required on damp or frigidly cold dry pavement.

3. The micro sipes designed in the snow tire is designed to catch snow and remain imbedded in the sipes (test have shown that embedded snow in the snow sipes offers more friction than rubber) and offers grip against black ice or hard compacted snow/ice covered streets whereas without the snow embedded in the sipes.

4. The quality of the rubber used and the overall structure of the tire is engineered primarily for the Winter Season, and nothing is comprised in it's execution since so much more innovation and technology has been invested that the Major Snow tire brands keep deploying more and more superior design and thought without the compromises of trying to build a tire for all seasons for all types of vehicles.

Yes, you can benefit from one type of 4wd / awd technology manufactured by one company vs another, but you can gain more of an advantage by going the Full blown winter tire route than using summer tires only.

Also vehicles that are 4wd or awd have zero advantages in the winter when it comes to braking. Ice is ice, snow is snow, the coefficient of friction is greatly reduced, and hence the drivetrain does not come into play whether 2wd, 4wd, awd etc. It comes down to the tires more so than drivetrain.

Cheers,

MadloR

[wwest]

I disagree, it is all about the drive. some drivers can do better with 2 wheel drive and regular tires than other drivers can do with 4 wheel with snow tires. Some drivers idea of getting un-stuck in snow is to floor it while others rock themselves out.

i guess, but you hear stories all the time about 2wd cars being brilliant in the snow with just snow tires. two extra tires that have power is just an advantage.

My point is, and I have done this myself, you can have a driver get hopelessly stuck in the snow and another driver can get into that car and drive it out of whatever it is stuck in. I am a retired cop and have driven 2 wheel drive police cars through some deep stuff with out chains. I have come upon drivers stuck in snow who thought they would need a wrecker to get out. I got into their car and got the car un-stuck in a matter of minutes. Some people will get stuck in 4 wheel drive vehicles with snow tires because they just don't know how to drive. I was a cop for 20 years and from my experience people get stuck because they are poor drivers. And when poor drivers get stuck they usually blame the car. 4 wheel drive is helpful in snow but the skill of the drive is most important.

I am not saying 4WD isn't helpful because I have owned 4WD vehicles for almost 30 years, they do give you an edge but you can have 2 different drivers in the same vehicles with the same equipment and one will get stuck while the other won't. There may be a situation where both drivers get stuck but the main factor is the driver.

And in your twenty years did your municipality even stick you with FWD patrol cars or front torque biased AWD..?

Red Lodge MT did and after a few were totalled they had to revise their wintertime driving procedures as a result.

[wwest]

its all about the tires. the system doesnt really matter.

It is AMAZING the technology found in todays modern "full" blown snow tires (not the M&S insignia found on four season tires).

1. Snow tires are designed with deep threads to counter deep snow and slush prior to any of the snow clearing trucks/equipment have been deployed.

Funny, those are the exact conditions wherein my Bridgestone Turanza summer tires give me quite stellar performance, it's only on ice or packed snow that I sometimes have to add tire chains.

2. The tire compound is designed to remain plyable in extremely cold -30F plus and yet still retain the flexibility required on damp or frigidly cold dry pavement.

Many years ago, say during the sixties, this stsatement had sound foundation, but today I would question the truth of it and ask for documentation confirming same.

3. The micro sipes designed in the snow tire is designed to catch snow and remain imbedded in the sipes (test have shown that embedded snow in the snow sipes offers more friction than rubber) and offers grip against black ice or hard compacted snow/ice covered streets whereas without the snow embedded in the sipes.

HUH...??

Where do you find a "snow" tire wherein the tread remains COLD enough not to, along with centrifical forces, to quickly discard ANY snow packed into the tread? And can you refer us to the test documentation.

4. The quality of the rubber used and the overall structure of the tire is engineered primarily for the Winter Season, and nothing is comprised in it's execution since so much more innovation and technology has been invested that the Major Snow tire brands keep deploying more and more superior design and thought without the compromises of trying to build a tire for all seasons for all types of vehicles.

Pure tire company marketing hype....Two sets of tires for EVERY vehicle.

Yes, you can benefit from one type of 4wd / awd technology manufactured by one company vs another, but you can gain more of an advantage by going the Full blown winter tire route than using summer tires only.

Also vehicles that are 4wd or awd have zero advantages in the winter when it comes to braking. Ice is ice, snow is snow, the coefficient of friction is greatly reduced, and hence the drivetrain does not come into play whether 2wd, 4wd, awd etc. It comes down to the tires more so than drivetrain.

Sorry, but this one is just flat WRONG.

You seem to be saying, as an analogy, that we should have brakes only one set of wheels, hopefully you would choose the front.

Cheers,

MadloR

[rlpiv]

Does anyone have experience with the AWD RX400h in mountain and snow conditions? Does the AWD function as well as traditional AWD? Does the Break function work well to control vehicle speed on downgrades and switchbacks, where 10mph is the desired speed, and minimizing use of regular breaks is the goal?

===========================================================================

I had to return my '07 RX400h because of the inferior ... yes completely IMPOTENT All Wheel Drive (AWD).

Please see my topic "RX400h .. impotent AWD" on March 30, 2007. The VSC gets in the way, and renders the AWD impotent !! I "traded down" to a RX350 which has an awsome AWD just like the '02 RX300 I had before. Please see the discussion from my 3/30/07 entry.

I have a friend with a Toyota 4-Runner that has a VSC switch. His vehicle acted like the RX400h AWD (he wasn't able to get our of his driveway) until he turned off the VSC, then that vehicle acted like the RX3XXs.

Good Luck.

rlpiv

[silvercorvette]

I disagree, it is all about the drive. some drivers can do better with 2 wheel drive and regular tires than other drivers can do with 4 wheel with snow tires. Some drivers idea of getting un-stuck in snow is to floor it while others rock themselves out.

i guess, but you hear stories all the time about 2wd cars being brilliant in the snow with just snow tires. two extra tires that have power is just an advantage.

My point is, and I have done this myself, you can have a driver get hopelessly stuck in the snow and another driver can get into that car and drive it out of whatever it is stuck in. I am a retired cop and have driven 2 wheel drive police cars through some deep stuff with out chains. I have come upon drivers stuck in snow who thought they would need a wrecker to get out. I got into their car and got the car un-stuck in a matter of minutes. Some people will get stuck in 4 wheel drive vehicles with snow tires because they just don't know how to drive. I was a cop for 20 years and from my experience people get stuck because they are poor drivers. And when poor drivers get stuck they usually blame the car. 4 wheel drive is helpful in snow but the skill of the drive is most important.

I am not saying 4WD isn't helpful because I have owned 4WD vehicles for almost 30 years, they do give you an edge but you can have 2 different drivers in the same vehicles with the same equipment and one will get stuck while the other won't. There may be a situation where both drivers get stuck but the main factor is the driver.

And in your twenty years did your municipality even stick you with FWD patrol cars or front torque biased AWD..?

Red Lodge MT did and after a few were totalled they had to revise their wintertime driving procedures as a result.

I retired back in 1990 so I don't know for sure but I am pretty sure they are stillusing RWD vehicles. My depatment did have 4WD vehicles but my guess is they were less than 5% of the total fleet. On very rare ocasions when there was a pediction of an unuasually large storm theyhad us report in to get chains put on our cars.

[wwest]

Red Lodge bought Ford Taruses as patrol cars in about '97.

[Jim Nazium]

AWD vehicles and 4WD have zero advantage in stopping distances over FWD or "Variable" versions of 2 and 4 WD.

I live through winters in an urban city that cripples all other major metropolitain cities. We have the best (due to the amount of experience) on average number of winter capable drivers. When coming to a stop from 35mph or 60mph and you are braking on snow covered ice, there is no 4wd system in the world that will give any sort of advantage. In fact, you will probaby experience longer stopping distances due to the overall drivetrain "weight / drag" from the extra momentum carried by the additional driveshaft and differentials.

I'm talking STOPPING, not Starting from a slippery condition. Bottom line, Tires... Full Blown Winter Tires.

[SOMEONE ELSE'S GOT MY NAME]

Does anyone have experience with the AWD RX400h in mountain and snow conditions? Does the AWD function as well as traditional AWD? Does the Break function work well to control vehicle speed on downgrades and switchbacks, where 10mph is the desired speed, and minimizing use of regular breaks is the goal?

===========================================================================

I had to return my '07 RX400h because of the inferior ... yes completely IMPOTENT All Wheel Drive (AWD).

Please see my topic "RX400h .. impotent AWD" on March 30, 2007. The VSC gets in the way, and renders the AWD impotent !! I "traded down" to a RX350 which has an awsome AWD just like the '02 RX300 I had before. Please see the discussion from my 3/30/07 entry.

I have a friend with a Toyota 4-Runner that has a VSC switch. His vehicle acted like the RX400h AWD (he wasn't able to get our of his driveway) until he turned off the VSC, then that vehicle acted like the RX3XXs.

Good Luck.

rlpiv

For every person who sez the hybrid AWD system is a failure in the snow, there are TWO people ready to say it's the driver's failure, if they make that complaint. The inflamitory views / pasionate views are the strong beliefs of each side, and never the 2 shall meet, it would seem. Just my observation. We're in the Flathead valley MT, during some winters, and we think it's great, and couldn't be happier w/ the 400h's performance.