AWD vs. FWD Performance...
- Thread starter SuperStretch18
- Start date
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Since the CX-7 is FWD, ALWAYS, and only AWD as an exception, I rather doubt that turning off TCS will still turn off the automatic engine derating/dethrottling in the lower gear ranges or even mid gear range while turning tightly.
Most modern day FWD and F/AWD have a pre-emptive TC, Traction Control ,mode wherein loss of directional control due to front wheelspin/slip is prevented via dethrottling, limiting teh engine torque production, in specific circumstances.
Sort of the inverse of ABS.
Most modern day FWD and F/AWD have a pre-emptive TC, Traction Control ,mode wherein loss of directional control due to front wheelspin/slip is prevented via dethrottling, limiting teh engine torque production, in specific circumstances.
Sort of the inverse of ABS.
CX-7 AWD... How it sort of works
The CX-7 AWD system is cheap and broken. See posts about a vibration issue... (flame)
Don't be fooled. The MazdaUSA Regional Engineer described the system to me in detail. They used the cheapest and simplest AWD system available... really, only a hydraulic clutch in the rear differential that grabs when the spin rate is different from the front wheels.
There are NO controlling electronics, no cooperation with the traction control system or anti-locks, nothing... and you get 100% front or 50/50. It doesn't have a clue what is happening to the car.
Neat trick... you can disengage it altogether by gently depressing the parking brake pedal until just when the tone sounds.
Do NOT compare this to any REAL AWD system (like the Torsen system in Audi and several others)... it ain't that good :mad:
The CX-7 AWD system is cheap and broken. See posts about a vibration issue... (flame)
Don't be fooled. The MazdaUSA Regional Engineer described the system to me in detail. They used the cheapest and simplest AWD system available... really, only a hydraulic clutch in the rear differential that grabs when the spin rate is different from the front wheels.
There are NO controlling electronics, no cooperation with the traction control system or anti-locks, nothing... and you get 100% front or 50/50. It doesn't have a clue what is happening to the car.
Neat trick... you can disengage it altogether by gently depressing the parking brake pedal until just when the tone sounds.
Do NOT compare this to any REAL AWD system (like the Torsen system in Audi and several others)... it ain't that good :mad:
Actually your info is completely false. Please quit spamming multiple threads with the same post complaining about your problem. Sorry you are having trouble, but your problem seems to isolated. I have over 40k on my CX-7 and no problems. The AWD system is actually one of the best in its price range, excellent system. This is how it really works:
Here is the explanation right out of the Mazda training manual:
"The CX-7 is equipped with Mazdas new active torque split all-wheel drive system, which
debuted on the MazdaSpeed6, featuring a more aggressive transfer of torque to the rear
axle in accordance with driving conditions. This intelligent system achieves a satisfying
balance between the interactive control over the vehicle that makes it particularly enjoyable
to drive, and confident handling stability necessary for snowy, wet or other uncertain road
surfaces/conditions; engine power and torque are faithfully and efficiently transferred to the
road surface for maximum performance.
The active torque split AWD system uses real-time data input on steering angle, yaw rate,
lateral G-force and engine status to determine road surface and driving conditions. The CX7
s onboard computer then automatically determines which of three different modes of
front/rear torque distribution should be engaged: Normal, Sport, or Snow (for slippery
surfaces). The active torque coupling mounted in front of the rear differential is
electronically controlled in accordance with the data provided by the computer, adjusting
front/rear wheel torque distribution between 100:0 and 50:50 to deliver optimum drive
power to each axle. The result is that the most power and traction are made available under
all conditions; positive acceleration and confident handling are provided regardless of
constantly changing road conditions, as well as the ability to fully balance the vehicle in a
turn by skilful use of the accelerator pedal.
Unlike many competitor offerings, the torque transfer system in the CX-7 seamlessly
integrates the inherent stability of all-wheel drive; because the active torque coupling is
controlled electronically, it can react to wheel slippage much more rapidly than conventional
gear- or fluid-controlled systems. To ensure consistent power delivery under all weather and
driving conditions, the Power Take-Off (PTO) system on the centre differential that
distributes torque to the rear axle is fitted with its own liquid-cooled cooling system. "
Once the computer has shifted into snow or sport mode it pre-loads the rear axle so you don't have to wait for slippage. As oppossed to the system in the 01-04 Tribute where the wheels had to actually slip before the AWD kicked in.
For those debating the TCS system here is the blurb from the manual on that:
"The braking system works in synergy with the CX-7s Dynamic Stability Control (DSC),
incorporating a traction control system (TCS), to exhibit an outstanding level of active
safety. The Dynamic Stability Control system is designed to activate when the vehicle is
taking a turn too quickly for the road conditions. DSC compares the driver's intended
direction (from the steering wheel angle) to the actual vehicle path; if the system senses
understeer or oversteer, it applies braking force, and reduces engine torque if required, to
correct the situation.
Traction control systems generally come in one of two primary systems: an ABS-based
system, or an engine management system. Both systems use the ABS wheel speed sensors
to determine if there is wheel spin (wheel speed greater than vehicle speed). The CX-7
system uses engine management to reduce the amount of power output by reducing fuel,
ignition timing and throttle position to reduce wheel spin. This system is superior to systems
that use the ABS brakes to slow down the spinning wheel ABS systems have a tendency
to be very jarring in their operation and can overheat the brakes if used for extended
periods of time. The CX-7s traction control system (TCS) deals with the problem of the
engine supplying too much power for road conditions right at the source; when wheel spin is
detected, the TCS simply reduces the engines power output until the wheel spin stops.
Here is the explanation right out of the Mazda training manual:
"The CX-7 is equipped with Mazdas new active torque split all-wheel drive system, which
debuted on the MazdaSpeed6, featuring a more aggressive transfer of torque to the rear
axle in accordance with driving conditions. This intelligent system achieves a satisfying
balance between the interactive control over the vehicle that makes it particularly enjoyable
to drive, and confident handling stability necessary for snowy, wet or other uncertain road
surfaces/conditions; engine power and torque are faithfully and efficiently transferred to the
road surface for maximum performance.
The active torque split AWD system uses real-time data input on steering angle, yaw rate,
lateral G-force and engine status to determine road surface and driving conditions. The CX7
s onboard computer then automatically determines which of three different modes of
front/rear torque distribution should be engaged: Normal, Sport, or Snow (for slippery
surfaces). The active torque coupling mounted in front of the rear differential is
electronically controlled in accordance with the data provided by the computer, adjusting
front/rear wheel torque distribution between 100:0 and 50:50 to deliver optimum drive
power to each axle. The result is that the most power and traction are made available under
all conditions; positive acceleration and confident handling are provided regardless of
constantly changing road conditions, as well as the ability to fully balance the vehicle in a
turn by skilful use of the accelerator pedal.
Unlike many competitor offerings, the torque transfer system in the CX-7 seamlessly
integrates the inherent stability of all-wheel drive; because the active torque coupling is
controlled electronically, it can react to wheel slippage much more rapidly than conventional
gear- or fluid-controlled systems. To ensure consistent power delivery under all weather and
driving conditions, the Power Take-Off (PTO) system on the centre differential that
distributes torque to the rear axle is fitted with its own liquid-cooled cooling system. "
Once the computer has shifted into snow or sport mode it pre-loads the rear axle so you don't have to wait for slippage. As oppossed to the system in the 01-04 Tribute where the wheels had to actually slip before the AWD kicked in.
For those debating the TCS system here is the blurb from the manual on that:
"The braking system works in synergy with the CX-7s Dynamic Stability Control (DSC),
incorporating a traction control system (TCS), to exhibit an outstanding level of active
safety. The Dynamic Stability Control system is designed to activate when the vehicle is
taking a turn too quickly for the road conditions. DSC compares the driver's intended
direction (from the steering wheel angle) to the actual vehicle path; if the system senses
understeer or oversteer, it applies braking force, and reduces engine torque if required, to
correct the situation.
Traction control systems generally come in one of two primary systems: an ABS-based
system, or an engine management system. Both systems use the ABS wheel speed sensors
to determine if there is wheel spin (wheel speed greater than vehicle speed). The CX-7
system uses engine management to reduce the amount of power output by reducing fuel,
ignition timing and throttle position to reduce wheel spin. This system is superior to systems
that use the ABS brakes to slow down the spinning wheel ABS systems have a tendency
to be very jarring in their operation and can overheat the brakes if used for extended
periods of time. The CX-7s traction control system (TCS) deals with the problem of the
engine supplying too much power for road conditions right at the source; when wheel spin is
detected, the TCS simply reduces the engines power output until the wheel spin stops.
Misinformation is right...
I don't know where Mazda3 got his misinformation.
I've stood under the car... there is NO center differential.
My information comes from standing face-face with the MazdaUSA district engineer and under my car. There are 3 parts... a PTO, a tail-shaft and an hydraulic rear differential... he pointed out each one.
I asked him about some of the things Mazda3 says in his post and he looked at me like I was nuts. He said "there are no electronics or cooperation with the traction control system or any other system. It's either on or off depending on tire rotational differences." In fact, he waxed on for several minutes about the Torsen system (good cars use that one) and how much better it was than Mazdas.
Get under your CX-7, Mazda3, and get a picture of that center differential you talk about.
Sorry... I can't imagine where you found that info but it is NOT for the CX-7. I've been given a tour by a Mazda engineer and touched every part in the AWD system myself!!
Oh, his bits about the TCS are probably true... don't see where it says that plays into AWD though?
And, Mazd3, if you had thrown $34,000 in the toilet on a CX-7... I imagine you'd be posting a lot as well. What else can one man do to fight a billion dollar liar like Mazda? Check the other posts out there about how Mazda deals with hard problems... they've been sued in several states... I'm not alone!
I don't know where Mazda3 got his misinformation.
I've stood under the car... there is NO center differential.
My information comes from standing face-face with the MazdaUSA district engineer and under my car. There are 3 parts... a PTO, a tail-shaft and an hydraulic rear differential... he pointed out each one.
I asked him about some of the things Mazda3 says in his post and he looked at me like I was nuts. He said "there are no electronics or cooperation with the traction control system or any other system. It's either on or off depending on tire rotational differences." In fact, he waxed on for several minutes about the Torsen system (good cars use that one) and how much better it was than Mazdas.
Get under your CX-7, Mazda3, and get a picture of that center differential you talk about.
Sorry... I can't imagine where you found that info but it is NOT for the CX-7. I've been given a tour by a Mazda engineer and touched every part in the AWD system myself!!
Oh, his bits about the TCS are probably true... don't see where it says that plays into AWD though?
And, Mazd3, if you had thrown $34,000 in the toilet on a CX-7... I imagine you'd be posting a lot as well. What else can one man do to fight a billion dollar liar like Mazda? Check the other posts out there about how Mazda deals with hard problems... they've been sued in several states... I'm not alone!
" The active torque coupling mounted in front of the rear differential "
The location isn't in the middle, its directly in front of the rear diff.
The information I quoted is right out of the Mazda Canada training manual. I've seen under my CX-7 many times I know whats under there. Being new you don't know that I have contacts high up at Mazda Canada and have conversed with engineers, reps, managers, and VP's many times about many topics. I can assure you that the AWD system in my CX-7, the CX-9, and the Speed 6 works exactly as I described. I'm not sure who you talked to or what his motive was for telling you what he did, but it's not right.
What you are describing sounds like the AWD system used in the old 01-04 Mazda Tribute.
The location isn't in the middle, its directly in front of the rear diff.
The information I quoted is right out of the Mazda Canada training manual. I've seen under my CX-7 many times I know whats under there. Being new you don't know that I have contacts high up at Mazda Canada and have conversed with engineers, reps, managers, and VP's many times about many topics. I can assure you that the AWD system in my CX-7, the CX-9, and the Speed 6 works exactly as I described. I'm not sure who you talked to or what his motive was for telling you what he did, but it's not right.
What you are describing sounds like the AWD system used in the old 01-04 Mazda Tribute.
Ok, normally I dont bother to debate with someone clearly out of his league. But, I have 34,000 reasons to be adamant about this topic. So, bear with me, this is worth reading!
First, before I continue with Mazda3s issues everyone who reads this needs to understand that the only reason Im posting anything is that my CX-7 AWD has a serious vibration at highway speeds and Mazda has declared it normal and is refusing to fix it or replace the vehicle. I need everyones help to determine if this is a widespread issue. As for Mazda3s assertion this seems to be isolated well, Mazda is aware of at least 4 units with this issue.
So, Mazda3, at the end of the day, if you are driving for several hours non-stop and experiencing no vibration you are part of my proof that Mazda is lying.
Now, as to your assertion that your post on the design of the system is right out of the Mazda Canada training manual then one has to wonder. How is it, then, that the information you provided is exactly identical to this posting from Dec-08?
http://www.mcx7.com/archive/index.php/t-1659.html
see superstretch18 post most of the way down the page.
How is it that you have access to the training manual? And, in a form that allows you to copy/paste? And, why didnt you use that resource instead of this persons posting? Also, interesting to note that the poster of this info gives no other information to backup the validity of his post. The only other source of this quote I have found is from a Canadian car forum review. It is identical to information posted on the MazdaSpeed6 and CX-9 but never appears for the CX-7 in any other source US or Canada. And, this source is NOT an official Mazda publication! By the way, mazda expert I have validated your information as mostly correct for the MazdaSpeed6 from an official Mazda publication. That means nothing here.
Note that the vehicles Mazda builds for Canada are different from the USA in many ways. Nothing that I have found, in over a year, provides that level of information for the US models.
Finally, although it is certainly possible that you have conversed with engineers, reps, managers, and VP's many times I find that HIGHLY unlikely unless, of course, you work for Mazda Canada. In which case, you have no credibility with me after my experiences with MazdaUSA. Note, too, that I work in management for a super-major oil company and I can tell you, it is nearly impossible to get access to VPs anytime much less many times! Mazda has actually refused my request to discuss this issue with someone at only the Director level forget about VP level.
I have stood face-face with the MazdaUSA District Engineer. This is the person in Mazda that makes the final decision as to whether a vehicle is broken, defective, repairable or a lemon and must be replaced. As I said before, he looked at me with astonishment when I asked him about the type of details you posted. He told me that the car I own, 2008 CX-7 AWD USA model, has only a PTO on the front transaxle and an hydraulic clutch in the rear differential that grabs when the spin rate is different from the front wheels. There are NO controlling electronics, no cooperation with the traction control system or anti-locks, nothing... you get 100% front or 50/50. It doesn't have a clue what is happening to the car. Why would a person of this authority, degreed engineering training and access directly to the Mazda engineers in Japan tell me something Mazda3 asserts is completely wrong. You decide who to believe Im going with the Mazda District Engineer.
So, as I have said, my concern is NOT with how it is designed it is with how it was ultimately built. And, according to Mazda, the defective vibrating AWD system is as designed.
Not only am I willing to testify to the information Ive presented here in a court of law it is quite possible I will be in the near future. So, Mazda3, if you dont mind either put up or shut up if you want to add value, then pass this info along to one of your VP friends. Perhaps they can influence Mazda to help me. Otherwise, you are just making childish noise in a serious conversation.
First, before I continue with Mazda3s issues everyone who reads this needs to understand that the only reason Im posting anything is that my CX-7 AWD has a serious vibration at highway speeds and Mazda has declared it normal and is refusing to fix it or replace the vehicle. I need everyones help to determine if this is a widespread issue. As for Mazda3s assertion this seems to be isolated well, Mazda is aware of at least 4 units with this issue.
So, Mazda3, at the end of the day, if you are driving for several hours non-stop and experiencing no vibration you are part of my proof that Mazda is lying.
Now, as to your assertion that your post on the design of the system is right out of the Mazda Canada training manual then one has to wonder. How is it, then, that the information you provided is exactly identical to this posting from Dec-08?
http://www.mcx7.com/archive/index.php/t-1659.html
see superstretch18 post most of the way down the page.
How is it that you have access to the training manual? And, in a form that allows you to copy/paste? And, why didnt you use that resource instead of this persons posting? Also, interesting to note that the poster of this info gives no other information to backup the validity of his post. The only other source of this quote I have found is from a Canadian car forum review. It is identical to information posted on the MazdaSpeed6 and CX-9 but never appears for the CX-7 in any other source US or Canada. And, this source is NOT an official Mazda publication! By the way, mazda expert I have validated your information as mostly correct for the MazdaSpeed6 from an official Mazda publication. That means nothing here.
Note that the vehicles Mazda builds for Canada are different from the USA in many ways. Nothing that I have found, in over a year, provides that level of information for the US models.
Finally, although it is certainly possible that you have conversed with engineers, reps, managers, and VP's many times I find that HIGHLY unlikely unless, of course, you work for Mazda Canada. In which case, you have no credibility with me after my experiences with MazdaUSA. Note, too, that I work in management for a super-major oil company and I can tell you, it is nearly impossible to get access to VPs anytime much less many times! Mazda has actually refused my request to discuss this issue with someone at only the Director level forget about VP level.
I have stood face-face with the MazdaUSA District Engineer. This is the person in Mazda that makes the final decision as to whether a vehicle is broken, defective, repairable or a lemon and must be replaced. As I said before, he looked at me with astonishment when I asked him about the type of details you posted. He told me that the car I own, 2008 CX-7 AWD USA model, has only a PTO on the front transaxle and an hydraulic clutch in the rear differential that grabs when the spin rate is different from the front wheels. There are NO controlling electronics, no cooperation with the traction control system or anti-locks, nothing... you get 100% front or 50/50. It doesn't have a clue what is happening to the car. Why would a person of this authority, degreed engineering training and access directly to the Mazda engineers in Japan tell me something Mazda3 asserts is completely wrong. You decide who to believe Im going with the Mazda District Engineer.
So, as I have said, my concern is NOT with how it is designed it is with how it was ultimately built. And, according to Mazda, the defective vibrating AWD system is as designed.
Not only am I willing to testify to the information Ive presented here in a court of law it is quite possible I will be in the near future. So, Mazda3, if you dont mind either put up or shut up if you want to add value, then pass this info along to one of your VP friends. Perhaps they can influence Mazda to help me. Otherwise, you are just making childish noise in a serious conversation.
SuperStretch18
Member
- :
- '07 CX-7 Sport, Black on Black; '04 Mazda3s
Dude, before you go attacking someone with my posts, you should search this forum first. I copied that information from Mazda3's post here from over a year ago.
http://www.mazdas247.com/forum/showthread.php?t=123693098
The post you linked was something I posted in December on another forum. I have the MS6 training manual in pdf form on my home PC. I can copy and past the AWD info from there later tonight if you like...
For s**** & giggles, I went to onlinemazdaparts.com and got a layout of the rear differential:
Sorry, that's not a direct connection diff, so I'm not sure what you are talking about. Either way, stop making an ass of yourself.
Dude... like totally... like when is someone going to like post that info for like the totally USA CX-7? What? Can't find it? Anyone can find the MS6 manual... it's posted. A bit like saying the Chevy Tahoe is the same as the Chevy Impala.
Besides, I'm not attacking, I'm defending... and trying to get my Mazda fixed or replaced.
Oh, and nice drawing... where's all the pieces that make it "active"? Looks like an hydraulic clutch mechanism attached to a limited slip differential. Which, like, dude, like, totally looks like what's under my car and what the MAZDA ENGINEER described. Awesome dude!!
Are there any adults on this forum?????
Besides, I'm not attacking, I'm defending... and trying to get my Mazda fixed or replaced.
Oh, and nice drawing... where's all the pieces that make it "active"? Looks like an hydraulic clutch mechanism attached to a limited slip differential. Which, like, dude, like, totally looks like what's under my car and what the MAZDA ENGINEER described. Awesome dude!!
Are there any adults on this forum?????
This is really starting to get quite comical. Who's out of their league? WOW!!! Hello pot?
As Superstretch stated he copied that info to the other forum with my permission. It is a fact that is the AWD system used in the CX-7. The validity of the info I provide has been proven many times over the years on this forum. I don't need and don't intend to prove the source of my info to you. I have no intention of helping your vendeta in anyway. 4 units out of about 30k is a chronic problem? I understand that you are mad, but you are grossly misinformed and not going to get any help here with the approach you are taking.
As Superstretch stated he copied that info to the other forum with my permission. It is a fact that is the AWD system used in the CX-7. The validity of the info I provide has been proven many times over the years on this forum. I don't need and don't intend to prove the source of my info to you. I have no intention of helping your vendeta in anyway. 4 units out of about 30k is a chronic problem? I understand that you are mad, but you are grossly misinformed and not going to get any help here with the approach you are taking.
The AWD systems are identical other than the MS6 has LSD and the CX-7 doesn't. Mazda is advertising 3 different vehicles with this AWD system. Do you really think they could get away with that if it weren't true? The lawsuit that proved that would run this small car company out of business. Are you on something? You sound like someone who has watched to many conspricy movies. I happen to know a thing or two about cars, I've been driving this CX-7 in extreme winter conditions for three years and it performs exactly as advertised.
SuperStretch18
Member
- :
- '07 CX-7 Sport, Black on Black; '04 Mazda3s
Gramatical corrections, great...
How about this for some advice; if you are looking for sympathy or help or whatever, don't butt into someone else's conversation with your sob story. Not very adult. Start your own damn thread.
And FWIW, I am immature at times and I'm, like totally, OK with that...
Some interesting stuff on youtube:
http://ca.youtube.com/watch?v=uOWGq1B8C84
http://ca.youtube.com/watch?v=R3D5Tm40T4I
I believe these videos have been posted before, but good for another view.
http://ca.youtube.com/watch?v=uOWGq1B8C84
http://ca.youtube.com/watch?v=R3D5Tm40T4I
I believe these videos have been posted before, but good for another view.
Mazda's Bad made me bad...
First, Id like to apologize for my part in a silly argument.
In my defense, I should not have gotten on this forum right after the last of several attempts to convince Mazda that this vibration is not normal. They refuse to work on it any further. Frankly, I think anyone would be mad as heck and I should know better than to get in debates when Im mad.
As to how the AWD works, that still seems to be in question. Your YouTube, Mazda3, was a good find. But, he didnt actually say the computers control the AWD, just that the drive train works in concert. What it does prove, now, is that the Mazda District Engineer doesnt seem to know how it works he told me hydraulic clutch and Mazda video says magnetic. I wonder if that isn't the source of the vibe... the clutches engaging/disengaging in a way they should not be? Actually, it really doesnt matter to me any longer. However it works, it vibrates and thats the problem Im trying to solve.
So, Mazda3, tell me. Do you (or anyone reading this) have a AWD CX-7 that does NOT vibrate after being driven at highway speeds for a few hours? Because that is as important as having one that does it proves to Mazda the vibe is not normal.
In any case, it appears that MazdaUSA is lying to avoid the cost of fixing my car... or they are just plain ignorant. The Mazda manager (District Engineer) who is deciding what is broken and what will be fixed doesnt even appear to actually know how the AWD system works. See why I am ready to scream?
First, Id like to apologize for my part in a silly argument.
In my defense, I should not have gotten on this forum right after the last of several attempts to convince Mazda that this vibration is not normal. They refuse to work on it any further. Frankly, I think anyone would be mad as heck and I should know better than to get in debates when Im mad.
As to how the AWD works, that still seems to be in question. Your YouTube, Mazda3, was a good find. But, he didnt actually say the computers control the AWD, just that the drive train works in concert. What it does prove, now, is that the Mazda District Engineer doesnt seem to know how it works he told me hydraulic clutch and Mazda video says magnetic. I wonder if that isn't the source of the vibe... the clutches engaging/disengaging in a way they should not be? Actually, it really doesnt matter to me any longer. However it works, it vibrates and thats the problem Im trying to solve.
So, Mazda3, tell me. Do you (or anyone reading this) have a AWD CX-7 that does NOT vibrate after being driven at highway speeds for a few hours? Because that is as important as having one that does it proves to Mazda the vibe is not normal.
In any case, it appears that MazdaUSA is lying to avoid the cost of fixing my car... or they are just plain ignorant. The Mazda manager (District Engineer) who is deciding what is broken and what will be fixed doesnt even appear to actually know how the AWD system works. See why I am ready to scream?
thank you for being civil.
I have an AWD cx-7 that does not vibrate. i have driven it from north east ohio to south carolina once, and south west ohio 4-5 times (4 hours to cincy) no vibrations.
and, yeah, it sounds like mazda is ******* with you....
First off, I question whether the person you talked too was an actual engineer or just a district parts/service rep. He doesn't know what he is talking about and if what he was saying about the awd was true Mazda would fire his ass for telling you.
I'm leaving for an out of town meeting right away. It's 2.5 hrs there and 2.5 hrs back. I've never noticed a vibration before, but I'll pay extra attention this time. I'll post my finding tonight.
This is the same link I gave earlier.
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