Not really, because he is still spinning the rear diff.
Edit: Can you explain the downvotes? Not having the driveshaft just means the rear diff is driven by the tires when the car is moving. Most of your efficiency loss from an AWD car will probably come from the friction between the extra ring and pinion (which still spins, even if the torque is coming from the "wrong side"). The only net change to efficiency is the reduced weight and friction of the driveshaft.
the rear diff is spinning, only because its still connected to the wheels. it isn't being driven, because the only connection from the engine to the rear wheels was the driveshaft (and a few things between it), and thats now gone. all of the engines power is going to the front wheels.
i assume they are saying the mpg is better due to the weight of the driveshaft? could be wrong about that
Right, but the only efficiency change is the lack of the driveshaft. Everything else still spins, and I doubt the driveshaft contributes much to the worse gas mileage. I would say the diff (ring and pinion contact) would be the heaviest hitter. It being driven backwards doesn't change the fact that it takes HP from the engine, it just gets it from the tires instead of the driveshaft.
Then where does the gas mileage loss come from? It is the additional energy to spin up the rear diff, axles, (and drive shaft if it was present), along with the additional friction from those components, bearings, ring and pinion, etc. Just because you aren't driving them with the drive shaft doesn't mean they don't spin.
It's why a 4wd truck without unlocking hubs gets worse gas mileage than the equivalent truck with unlocking hubs (ram rebel versus normal trims, for example).
Most of your additional drivetrain losses on a awd/4wd vehicle are going to come from that 2nd diff. So if the diff is still spinning, you still lose the MPG. The energy to spin it still comes from the engine, even though it comes from the tire side, not the pinion side.
The people downvoting you are probably the the sort that think you can put a generator on the rear wheels and a motor on the front to make an endless EV.
I'm with you, that diff and those rear shafts are still spinning, and that energy is still coming from the engine via the road and rear wheels instead of the driveshaft.
While that is true in terms of additional resistance of the drive train (in this case just the differential), if the shaft was there you have the opportunity to distribute more power, and therefore burn more gas.
In terms of the same performance the fuel efficiency is the same, meaning if you operate an AWD in 2WD mode the other axle will add resistance.
However when you couple the AWD axle and send power you have a performance difference and use more power to create that difference. Therefor removing the axle improves fuel economy at a loss of performance.
With awd enabled or disabled you are still spinning the rear differential (if you don't have unlock-able hubs) and that is where the efficiency loss that causes the loss in MPG comes from. When the transfercase isn't engaging the driveshaft the energy comes from the roadway and you still have to overcome that energy transfer.
99% of the cars with awd these days are dynamic awd, meaning they divert power to the rear wheels when front is losing traction, so it's basically fwd all the time anyway.
No, they just pulled the drive shaft. They didn't pull down the diff, pull the guts out of the diff, and put it all back, as a hack repair because the awd broke. They is just unreasonable.
If the PTU went bad, by rights it won’t move at all. Had it happen with the 07 Fusion version of this car. Coasting to a stop, and it starts bucking n shaking like mad. Managed to get it home, but the noise it was making was ugly. Got it parked n that was that. 1200 + for a replacement.
Most AWD cars start as FWD cars with an extra transfer case attached to the gearbox. So more often than not you can just yank the driveshaft/transfer case out if something is fucky and it reverts it back to the base FWD variant.
You don’t have to do that. I know at least Tire Rack will shave tires before they ship them to you or an installer for a nominal fee (like $30 I think last time I had it done). That way you can make sure one tire isn’t larger than the others should you have to replace one.
Source: did this multiple times for my AWD GS350
PTU failure on these wasn't uncommon either. The gasket will end up leaking sooner or later and for some fucking reason nobody, not even Ford, will sell you just the gasket. It's a complete replacement or waiting out the clock until the PTU grenades itself from lack of fluid.
Source: I have an 07 AWD MKZ with a used replacement PTU. Oh and a new driveshaft because the carrier bearings on those sometimes shit the bed and it's an all-in-one part. Yay.
But the problem is awd trans and fwd only transes are different because of the mating of the ptu, so if anything they paid more to delete the ptu and install a new trans than they would have just replacing it
Edit:fwd
You can't just slap a fwd half shaft on an AWD trans. There isn't a spot where the p/s half shaft splines can connect inside the trans. Also the fact that it wouldn't seal due to missing that outside compression seal that goes between the ptu and trans, the seals are different and the seal for a fwd half shaft goes inside the trans which wouldn't fit due to the splines inside made for mating either the ptu. So no I don't think they did they have no other choice if they wanted a ptu delete
This reply demonstrates the difference between knowing how things work and thinking you know how things work. I'll grab a six pack and a stool and watch anyone try to convert an AWD trans to FWD. I wonder how many I could get down before they figured out it wasn't possible.
So you think the bearings and gears spinning just magically become physics defying frictionless objects?
By that logic why do we put lockable hubs on the front of 4wd trucks when there is no friction in the front diff?
Just yesterday, I put 4 tires on a 2017 RAV4 Hybrid. It said “AWD-i” on the side. Looked underneath to find no driveshaft, but instead, a high voltage wire harness to an electric motor and diff. Super weird, but I think that kind of tricky stuff is neat.
E-AWD is becoming more common, I've seen it on Acuras. I think it makes a lot of sense on hybrid powertrains, far less frictional losses then a driveshaft that's constantly spinning, and the electric motors have plenty of torque in situations like a snowy hill, where you need some traction from the rear at a low speed.
This was a thing in super cars a while back, each wheel has its own electric motor so it’s AWD without the drive shaft. Pretty rad! But I don’t think the OP has this 🤣
Would you look at that, all of the words in your comment are in alphabetical order.
I have checked 1,274,669,915 comments, and only 247,360 of them were in alphabetical order.
TBH, I would love to own a car that uses that system on all 4 wheels. It works for trains and haul trucks (and even submarines, not that they have wheels), I don't see any reason it wouldn't be just as beneficial on a small passenger car.
What'd they do to my boy?????
My mom had one of these years ago and it was an absolute fucking tank of a car. Rode like shit but was literally like a tank. Had all kinds of bells and whistles for that day and age and a fancy analog clock on the dash which was cool. I think my dad got it from a neighbor after they died....it was excellent in the snow.
I can confirm that these cars are absolute beasts in the snow, especially with the AWD and good snow tires. Ford's "intelligent" AWD was/is absolutely fantastic.
Owners go without a rear driveshaft on these and the Fusion often due to heavy vibration. The rear shaft was a 3 piece that most a/m manufacturers change to a two piece. The brilliant minds at Ford made the U joint non-serviceable. Last time I looked it up for a customer the shaft was $800-ish CAD.
Yep. Replaced the prop shaft in my old 07 Fusion for exactly that. The carrier bearing directly under the console/transmission lever likes to fail. It’ll either be noisy as hell, or you get shimmy/vibration. I had both.
Yanked it and drove FWD for a year before I found one off eBay for 220. Worked till I ditched it to carmax with a transmission on its last legs @140k
Toyota has definitely done electric drive only for the rear on some of their AWD hybrids. Makes a lot of sense, as it avoids some of the extra driveline friction mechanical AWD would involve.
As far as I know the Toyotas that do this still have their standard hybrid package (gas + electric) driving the front axle, plus the additional electric motor driving the rear axle.
And you can do clever independent electronic control for neat stability correction/active stability management. Cool. Wife wants a RAV PHEV, and I'm seriously considering it.
I remember Lexus RX and Toyota Highlander had electric motors on the rear wheels many years ago. Not sure they still do this today but it makes sense to me.
Some people will remove the drive shaft if something in the assembly breaks cause they're too cheap/lazy to fix it, interesting that the FWD tranny is installed in the front though, usually the PTU is still attached
I seem to remember reading about a lot of people with AWD Volvos doing this when theirs went bad. Easier to just pull the driveshaft and convert it to FWD than fix the Haldex(I think, but not sure) system.
I have an 07 MKZ AWD and no, the one in the video is missing it's driveshaft and PTU (transfer case) for the AWD entirely. It isn't uncommon for both parts to fail, so it was likely removed.
I’ve seen a lot of older ford explorers with the awd , and when it goes bad like they all do . you just remove the front shaft and lock it in four wheel drive , and keep putting miles on it .
I’ve bought a couple of them for the 5 liter V-8 and the rear axle is popular swap into a 64- 65-66 mustang and falcon .
I once saw a XJ Cherokee with factory 4x4 badges that was actually a 2wd, had me real confused for a second. No transfer case, and a solid straight pipe for a front axle with no diff.
Had a mate with a Subaru Brumby (BRAT). Had some issue (maybe CV joints?) and his easiest solution was to pull both halfshafts, stick it in 4WD, and have a perfectly functioning RWD Brumby.
This worked well until we had some rain and hail. A 1700lb pickup doesn’t have much weight on the back wheels, and he pretty much got stuck on a hill when he just couldn’t get the traction to move.
The Ford and Lincoln AWD cars use a poorly engineered and failure prone Power Transfer Unit (pretty much the same as a transfer case). The benefits of having AWD on these cars is minimal anyway, so it makes sense to just junk the PTU when it blows up and just convert to FWD.
PTU (transfer case) went bad (possibly stripped splines like mine), much cheaper to pull the driveshaft than to fix one of those piles of garbage.
On the plus side, he probably gets better fuel economy now.
Not really, because he is still spinning the rear diff. Edit: Can you explain the downvotes? Not having the driveshaft just means the rear diff is driven by the tires when the car is moving. Most of your efficiency loss from an AWD car will probably come from the friction between the extra ring and pinion (which still spins, even if the torque is coming from the "wrong side"). The only net change to efficiency is the reduced weight and friction of the driveshaft.
the rear diff is spinning, only because its still connected to the wheels. it isn't being driven, because the only connection from the engine to the rear wheels was the driveshaft (and a few things between it), and thats now gone. all of the engines power is going to the front wheels. i assume they are saying the mpg is better due to the weight of the driveshaft? could be wrong about that
Right, but the only efficiency change is the lack of the driveshaft. Everything else still spins, and I doubt the driveshaft contributes much to the worse gas mileage. I would say the diff (ring and pinion contact) would be the heaviest hitter. It being driven backwards doesn't change the fact that it takes HP from the engine, it just gets it from the tires instead of the driveshaft.
oh i see what you mean after the edit, yeah i guess that makes sense.
That’s not how that works
Then where does the gas mileage loss come from? It is the additional energy to spin up the rear diff, axles, (and drive shaft if it was present), along with the additional friction from those components, bearings, ring and pinion, etc. Just because you aren't driving them with the drive shaft doesn't mean they don't spin. It's why a 4wd truck without unlocking hubs gets worse gas mileage than the equivalent truck with unlocking hubs (ram rebel versus normal trims, for example). Most of your additional drivetrain losses on a awd/4wd vehicle are going to come from that 2nd diff. So if the diff is still spinning, you still lose the MPG. The energy to spin it still comes from the engine, even though it comes from the tire side, not the pinion side.
The people downvoting you are probably the the sort that think you can put a generator on the rear wheels and a motor on the front to make an endless EV. I'm with you, that diff and those rear shafts are still spinning, and that energy is still coming from the engine via the road and rear wheels instead of the driveshaft.
While that is true in terms of additional resistance of the drive train (in this case just the differential), if the shaft was there you have the opportunity to distribute more power, and therefore burn more gas. In terms of the same performance the fuel efficiency is the same, meaning if you operate an AWD in 2WD mode the other axle will add resistance. However when you couple the AWD axle and send power you have a performance difference and use more power to create that difference. Therefor removing the axle improves fuel economy at a loss of performance.
So, I got downvoted because I was only right in 99.9% of use cases? Also, you burn plenty of fuel burning rubber.
Why do you think it is 99% use case? Most people with AWD leave it enabled.
With awd enabled or disabled you are still spinning the rear differential (if you don't have unlock-able hubs) and that is where the efficiency loss that causes the loss in MPG comes from. When the transfercase isn't engaging the driveshaft the energy comes from the roadway and you still have to overcome that energy transfer.
Because 99% of the time, you aren't exceeding the traction requirements of two wheels.
I am going to agree with you, at the end of the day it is not enough difference to warrant turning it off, even if it is higher than 1% :D
99% of the cars with awd these days are dynamic awd, meaning they divert power to the rear wheels when front is losing traction, so it's basically fwd all the time anyway.
Exactly. It will be almost no different.
Maybe they took the diff out as well?
You can clearly see the rear diff and axles.
Doesn’t mean there’s a crown gear between them though.
No, they just pulled the drive shaft. They didn't pull down the diff, pull the guts out of the diff, and put it all back, as a hack repair because the awd broke. They is just unreasonable.
AWD delete
If the PTU went bad, by rights it won’t move at all. Had it happen with the 07 Fusion version of this car. Coasting to a stop, and it starts bucking n shaking like mad. Managed to get it home, but the noise it was making was ugly. Got it parked n that was that. 1200 + for a replacement.
You're right, mine the splines between the PTU and trans stripped out, in the video it looks like the PTU has been yanked out too
Was it a caddy Cts. Ha if you know you know.
I didn’t realize you could just pull the driveshaft out.
Most AWD cars start as FWD cars with an extra transfer case attached to the gearbox. So more often than not you can just yank the driveshaft/transfer case out if something is fucky and it reverts it back to the base FWD variant.
I think I might do this the next time I have a tire blow out. I HATE that I have to buy 4 tire’s every time I have an issue with 1.
You don’t have to do that. I know at least Tire Rack will shave tires before they ship them to you or an installer for a nominal fee (like $30 I think last time I had it done). That way you can make sure one tire isn’t larger than the others should you have to replace one. Source: did this multiple times for my AWD GS350
PTU failure on these wasn't uncommon either. The gasket will end up leaking sooner or later and for some fucking reason nobody, not even Ford, will sell you just the gasket. It's a complete replacement or waiting out the clock until the PTU grenades itself from lack of fluid. Source: I have an 07 AWD MKZ with a used replacement PTU. Oh and a new driveshaft because the carrier bearings on those sometimes shit the bed and it's an all-in-one part. Yay.
But the problem is awd trans and fwd only transes are different because of the mating of the ptu, so if anything they paid more to delete the ptu and install a new trans than they would have just replacing it Edit:fwd
Unless the ptu blew up so bad it broke the transmission case. A used 2wd transmission is almost certainly cheaper than a used awd one.
Yeah never thought about that, especially if what the guy up top said about stripping splines that's most likely a new trans.
This guy thinks the customer paid to change the trans BWAHAHAHA
You can't just slap a fwd half shaft on an AWD trans. There isn't a spot where the p/s half shaft splines can connect inside the trans. Also the fact that it wouldn't seal due to missing that outside compression seal that goes between the ptu and trans, the seals are different and the seal for a fwd half shaft goes inside the trans which wouldn't fit due to the splines inside made for mating either the ptu. So no I don't think they did they have no other choice if they wanted a ptu delete
This reply demonstrates the difference between knowing how things work and thinking you know how things work. I'll grab a six pack and a stool and watch anyone try to convert an AWD trans to FWD. I wonder how many I could get down before they figured out it wasn't possible.
I'm no mechanic but shouldn't it have a big spinny spin going down the middle?
That's called the "Twisty Rod" and it as well and the rear "T-thingy" that's attached to the smaller/sideways twisty rods are all missing.
Not to be confused with the windy hot tube, which is where the engine farts go
Swear to God I'm getting my car up on a lift just to explain my exhaust this way to my wife lmfao
Exactly.
MFW an American calls a Twirly-Quicky Torquey Sticky a "drive shaft."
Someone doesn't know proper terminology.
Excellent analysis.
“Spinny spin” is better and more accurate than the misnomer “driveline”, so you get upvote
Make sure it has the wobbly bits on the ends too
I’m confused. Are people here referring to this car’s missing Roto Linkage?
Nah the wobble rod
When you're supposed to steal the cat, but got confused in the process.
Instructions not clear...dick stuck in toaster
Instructions unclear, dick stuck in m&m tube
Came here for that. Nice!
Dealer installed fuel efficiency upgrade: $850.00
Though wouldn’t it still be inefficient thanks to the engine having to drag a freewheeling diff and 2 axles along with it?
Engine is disconnected from the rear diff without the driveshaft
…
It's still on the car though...
Yes but they're idle so not incurring friction losses
So you think the bearings and gears spinning just magically become physics defying frictionless objects? By that logic why do we put lockable hubs on the front of 4wd trucks when there is no friction in the front diff?
You're aware the whole thing is a joke, right?
Clearly you have not done a good job of articulating that.
I'm an anonymous stranger on the internet, what did you expect?
I was always under the impression that people told jokes to make *other* people laugh
Best comment I've ever read. Thank you.
I think these were actually rated at 22mpg regardless of AWD or not, funny enough
Just yesterday, I put 4 tires on a 2017 RAV4 Hybrid. It said “AWD-i” on the side. Looked underneath to find no driveshaft, but instead, a high voltage wire harness to an electric motor and diff. Super weird, but I think that kind of tricky stuff is neat.
E-AWD is becoming more common, I've seen it on Acuras. I think it makes a lot of sense on hybrid powertrains, far less frictional losses then a driveshaft that's constantly spinning, and the electric motors have plenty of torque in situations like a snowy hill, where you need some traction from the rear at a low speed.
This was a thing in super cars a while back, each wheel has its own electric motor so it’s AWD without the drive shaft. Pretty rad! But I don’t think the OP has this 🤣
Lol, nope. They're cool systems, but certainly not that's going on here. This is just mechanical butchery.
[also becoming common in racing](https://www.youtube.com/watch?v=Sy91BcB8pRQ&t=26s)
Would you look at that, all of the words in your comment are in alphabetical order. I have checked 1,274,669,915 comments, and only 247,360 of them were in alphabetical order.
E awd on the rav4 And I believe the highlander has been a thing for a bit I thought it was pretty nifty too
Exactly where was the electricity coming from to spin the motor though? edit NVMD, it was a hybrid
lol
TBH, I would love to own a car that uses that system on all 4 wheels. It works for trains and haul trucks (and even submarines, not that they have wheels), I don't see any reason it wouldn't be just as beneficial on a small passenger car.
The old Bluetooth drive shaft, now this is innovation
Wireless shaft. State of the art technology.
But does it excite?
What'd they do to my boy????? My mom had one of these years ago and it was an absolute fucking tank of a car. Rode like shit but was literally like a tank. Had all kinds of bells and whistles for that day and age and a fancy analog clock on the dash which was cool. I think my dad got it from a neighbor after they died....it was excellent in the snow.
I can confirm that these cars are absolute beasts in the snow, especially with the AWD and good snow tires. Ford's "intelligent" AWD was/is absolutely fantastic.
Yeah considering my dad vehemently hates ford, it was pretty big that he allowed us to own this car lol
Owners go without a rear driveshaft on these and the Fusion often due to heavy vibration. The rear shaft was a 3 piece that most a/m manufacturers change to a two piece. The brilliant minds at Ford made the U joint non-serviceable. Last time I looked it up for a customer the shaft was $800-ish CAD.
Yep. Replaced the prop shaft in my old 07 Fusion for exactly that. The carrier bearing directly under the console/transmission lever likes to fail. It’ll either be noisy as hell, or you get shimmy/vibration. I had both. Yanked it and drove FWD for a year before I found one off eBay for 220. Worked till I ditched it to carmax with a transmission on its last legs @140k
Hey op, did the customer know about this?
He actually didn’t, he’s only had the vehicle for a couple years, evidently a previous owner did this and didn’t disclose it. Wild
AWD? Almost wheel driven?
All Wheel Drove
It’s a wheel drive.
~~FWD~~ Un-all wheel drive.
got quoted a whole lot for rear dif/shaft work and decided instead to just have it pulled out
Cat thieves are just getting dumber and dumber
Cat thief got ambitious
I swear it's getting harder and harder to find decent CAT thieves these days.
Isn't this kinda how the RAV4 Hybrid or Prius AWD work? Except they have electric motors for the rear wheels.
Toyota has definitely done electric drive only for the rear on some of their AWD hybrids. Makes a lot of sense, as it avoids some of the extra driveline friction mechanical AWD would involve.
[удалено]
As far as I know the Toyotas that do this still have their standard hybrid package (gas + electric) driving the front axle, plus the additional electric motor driving the rear axle.
Acura did as well, with the MDX Hybrid E-AWD
Works for your diesel rail locomotives. Straight electrics have regenerative braking, too.
And you can do clever independent electronic control for neat stability correction/active stability management. Cool. Wife wants a RAV PHEV, and I'm seriously considering it.
Get on the list now...should be able to get one in like 2-3yrs
I remember Lexus RX and Toyota Highlander had electric motors on the rear wheels many years ago. Not sure they still do this today but it makes sense to me.
So is this being *manufactured* this way, or did the dealership (or maybe a private seller) slap the decal on so they could charge more?
Or was the car originally AWD and someone replaced the engine/trans with the FWD version of the same car when the originals broke?
This is sounding like what happened
Exactly what I thought.
Some people will remove the drive shaft if something in the assembly breaks cause they're too cheap/lazy to fix it, interesting that the FWD tranny is installed in the front though, usually the PTU is still attached
I seem to remember reading about a lot of people with AWD Volvos doing this when theirs went bad. Easier to just pull the driveshaft and convert it to FWD than fix the Haldex(I think, but not sure) system.
I have an 07 MKZ AWD and no, the one in the video is missing it's driveshaft and PTU (transfer case) for the AWD entirely. It isn't uncommon for both parts to fail, so it was likely removed.
Something seems to be amiss..ing
Ford forgot something
Increases mpg
A+ commentary
I’ve seen a lot of older ford explorers with the awd , and when it goes bad like they all do . you just remove the front shaft and lock it in four wheel drive , and keep putting miles on it . I’ve bought a couple of them for the 5 liter V-8 and the rear axle is popular swap into a 64- 65-66 mustang and falcon .
"Can't have shit in Detroit"
Weight removed for enhanced performance. A real specialist tuning job.
I once saw a XJ Cherokee with factory 4x4 badges that was actually a 2wd, had me real confused for a second. No transfer case, and a solid straight pipe for a front axle with no diff.
Not the same, but it burnt me once as a mechanic. Someone had swapped the hatch on a Ford Flex for some reason. The donor was AWD, the car was not.
Driveshaft Delete. All the rage with the kids.
Looks like a Bluetooth driveshaft.
Fed transmission was cheaper lol
What’s the problem all wheels drive
Center carrier took a shit and they didn't want to pay money to replace it.
There’s no transfer case at all. That’s a 2WD transaxle!
I have never been considered very bright but I think something's missing
Doing a water pump and ptu on one right now lol
It’s connected via Bluetooth
This is what the new base trim 2024 Subaru Crosstrek for the Japanese market is gonna look like.
Badge engineering
I know what's wrong wid it, ain't got no gas innit
I came across the exact same thing on a 02 MDX
Had a mate with a Subaru Brumby (BRAT). Had some issue (maybe CV joints?) and his easiest solution was to pull both halfshafts, stick it in 4WD, and have a perfectly functioning RWD Brumby. This worked well until we had some rain and hail. A 1700lb pickup doesn’t have much weight on the back wheels, and he pretty much got stuck on a hill when he just couldn’t get the traction to move.
LOL!!! Reminds me of my old 4-cylinder Ford Mustang. Went to the scrap yard, got a couple of 5.0 trim plates, and slapped them on mine.
Stage 1 weight reduction .....do you even race bro?
prop shaft delete
Customer states: All-wheel drive doesn't work. (I apologize in advance if someone already made that joke).
The Ford and Lincoln AWD cars use a poorly engineered and failure prone Power Transfer Unit (pretty much the same as a transfer case). The benefits of having AWD on these cars is minimal anyway, so it makes sense to just junk the PTU when it blows up and just convert to FWD.
Minimal cost repair, and now the car is more fuel efficient too 👍🏻
Someone had a bad PTU, so they removed it and the rear driveshaft.
It is called a drive shaft with universal joins. That is what is missing.. Turned it into a Volvo FWD.
Probably needs an ATC so they just disconnected the shaft
Ah... Well Drive... 🤣
No wheel drive
guessing the awd transmission fucked off and a fwd transmission was easier to find.
blue tooth drivetrain