Crossover AWD / 4WD Systems
Вставка
- Опубліковано 6 лип 2024
- TIMELINE:
0:00 Introduction
0:35 Power Transfer Unit (PTU)
1:40 The Link Shaft (Axle shaft)
2:22 Transaxle differentials and the link shaft connection
4:16 The PTU connection to the differential case
6:00 The internal parts of a PTU
7:40 The spool and the ring gear
8:10 The PTU spool connection to the transaxle differential case
8:48 The transaxle final drive underdrive gear ratio of 4.356:1
10:05 The PTU gear overdrive ratio of 0.439:1
11:58 The rear axle gear ratio of 2.2779:1
13:05 Two different axle gear ratios on the same vehicle
14:36 The rear driveline spins at an RPM related to the rear axle gear ratio, not the front final drive gear ratio.
15:33 The rear driveline does not always have a direct connection to the pinion gear
18:08 On-vehicle view of the PTU
19:58 On-vehicle view of the three-piece driveline
21:12 On-vehicle view of the rear differential with a clutch pack connection
24:15 Summary
ABOUT US:
Weber State University (WSU) - Automotive Technology Department - Transmission Lab. This episode covers the operation of a typical Crossover All Wheel Drive (AWD/4WD) system with a Power Transfer Unit PTU) on a Crossover SUV. A Crossover SUV is a vehicle that is primarily front-wheel drive but can have an all-wheel drive or 4-wheel drive option. We teach current vehicle technologies to our automotive students at Weber State University and online. For more information visit: www.weber.edu/automotive
This video was created and edited by Professor John D. Kelly at WSU. For a full biography, see www.weber.edu/automotive/J_Kel...
Visit my other youtube channel / vibratesoftware to see the amazing NVH app for vibration diagnosis!
This video helps satisfy the requirements of the following NATEF Tasks:
3.F.5 - 4WD/AWD - Diagnose noise, vibration, and unusual steering
concerns; determine necessary action - Priority Level 3
Question for Teachers:
1. What is a Crossover SUV?
2. What the meaning of the PTU abbreviation?
3. Is a PTU used on a vehicle with a transversely-mounted engine or a longitudinally-mounted engine?
4. To what part is the PTU housing attached?
5. To what transaxle part is the PTU spool and ring gear attached?
6. What effect does the PTU have on the front differential action of the transaxle?
7. Is the rear driveshaft driven faster or slower than the PTU spool and ring gear?
8. What is the Front transaxle gear ratio of the vehicle in the video?
9. What is the rear axle gear ratio of the vehicle in the video?
10. How can there be two different gear ratios on the same vehicle and still have all the tires spin at the same speed?
11. How is power transferred from the driveline (Propeller shaft) to the rear axle?
12. What is the purpose of the electrical connector at the rear axle?
13. Name two conditions under which power transferred to the rear axle?
14. Tell me one thing you learned from this video
DONATE TO OUR DEPARTMENT
Please consider a donation to the Department of Automotive Technology at Weber State University here: advancement.weber.edu/Automotive
I've searched and watched almost every video on UA-cam about how AWD works over the past few days, and only Weberauto gave me a clear explanation. thank you very much! This video is the same as all Weberauto videos I've seen before, each one is a forever classic.
One of the most useful and well put together videos on the internet. Full stop. Taking a complex subject and making it simpler. Great teacher. I have learnt so much.
THIS IS WHAT I HAVE BEEN MISSING. THIS REALLY CLEARS THINGS UP. I REBUILT A 6F35 TRAND IN MY ESCAPE AND PULLED THE PTO WHILE DOING IT AND COULD NOT FOR THE LIFE OF ME FIGURE OUT WHAT ACTUATES THE 4WD. THIS IS CONFUSIN AS 09 ESCAPES COME IN AWD AND 4WD AND THE PTO'S AND TRANSMISSIONS ARE EXACTLY THE SAME. NOW I KNOW THE ACTION IS ALL AT THE REAR OF THE VEHICLE.
what a great introduction to CUV AWD - much appreciated
All of Prof. Kelly's videos are thoughtful and very instructive. I am enjoying them very much! Thank you!
I rarely have enjoyed such a clear and well done video explaining mechanics in trully simple and understandable way ! I myself am a teacher (professor..but in forest entomology...hence that bee flying in at 11:18 :-) but love to understand my vehicle...and finally, after reaching this video I got a really clear picture and answers to my understanding of an AWD ! Not being a native English speaker myself, it even adds to a brilliantly done video (I believe) which obviously stirred quite an attention (positive comments(questions). Thanks a lot for teaching on line. That's what education is all about - to grab a student's attention ! Perfect !
Thank you very much!
Thats what I needed to know. Thank you sir, for such detailed information. Very good job indeed.
Thank you!
Thanks for the NVH class today. learned a few things on the pico scope
+Piston Slap Thank you!
You're a remarkable teacher! I've learned and connected so many dots because of this video, thank you!
John, your video in these units cleared up a lot of mystery for me. Thank you!
Glad to help. Thanks for watching
Thank you very very much Prof. Kelly. You are my life time the best teacher who show me the kindness and clear explanation about automotive technology which I have to imitate your accurate but easy to follow and understand teaching method to my friends and customer.
Thank you for not only explaining, but also showing us how the system works.
Thank you
Respect for the amount of energies and time put on this video
Fully explained. Simply brilliant explanation. Many thanks for that.
Excellent tutorial as always Sir ! Thank you for your lucid explanations , as always.
These videos are amazing I really appreciate the effort you put into these.
Thank you
Well you made Crossover AWD easy to understand and only needed to watch the video one time . Great teaching tool for kids in Autoshop . I'm a Heavy Duty Truck and Coach / Heavy Equipment Tech that's about to downsize from my GMC Yukon to a AWD Crossover Now that I understand the power transfer to rear and see that it's somewhat heavier then visioned , I will add AWD to my search list . Great Video !
Another informative session downloaded to my memory, Thank you.
Thank you!
the ratio of likes to unlikes just shows the quality of video you have made here sir. That was a really good and handy explanation. I just saw the channel, I hope there's more on the power trains of of cars.
Thank you Sir...this is the Suzuki SX4 AWD system in a nut shell. Great video!
Hi John, thanks a lot for the great video. you're such a great teacher, explaining things in a step-by-step, crystal clear manner. i've been watching a lot of your other videos to fulfill my curiosity and learned heaps from. looking forwards for your future publishes, cheers.
+larry li Thank you!
You have taken to another world, amazing knowledge even engineers could not understand the mechanism.Thanks for the information
Glad it was helpful!
Best description on a Toyota AWD system so far. Thanks!
Thank you!
Thank you sir! Wonderful explanation. I just bought my first sideways engine (transverse) AWD vehicle and I needed to understand how the drive train is different than my so called 4x4 truck. So my 2014 AWD Volvo XC90 has transaxle, open diff in front and open diff in rear, but is sometimes has both front and rear axles drive via the PTU "Bevel Gear" and Haldex clutch assembly on the front to rear propeller shaft.
Glad it helped. Thanks for watching. Haldex is used by many vehicle manufacturers
Thank you for this very informative video. I am a retired auto body technician and I am always trying to learn as much as I can with regards to AWD ,PTU units etc. Your video was very helpful and I have save it for future reference. Thanks again. Canada
Thank you!
thanks for sharing, such a great video. Indeed Subaru transmission review would be awesome :)
It clears so many doubts, thanks a lot.
Thank you!
This video summarizes what 'compact SUVs' a.k.a. crossovers are capable of. The drivetrain components on these crossovers are too fragile for serious off-road use (barring occasional dirt/gravel trails).
Thank you for this anatomy lesson, Professor John D. Kelly
That was a terrific video, I had some questions on how my Highlander AWD Transmission got the power to the rear wheels and you answered them for me. THANKS
Thank you!
My pleasure , that's a lot of work you put in to produce the video, thanks again. - L
My God I love to watch your teachings on Power trane , very good work Sir... Steve in Canada
Thank you very much!
Clear and complete explanation! Thank you 🙏
Thank you
Great videos-Thanks from an old mechanic(technician)!!!
john james Thank you!
WOW. Thank you for the tour. Well presented and recorded. Subscribed.
Your videos are very informative! Thank you sir!
Thanks for watching!
Appreciate the information shared through this video. Thank you!
Thank you
working on my 2002 ford escape towed away without dollies and was mystified why I have no rear wheel drive at any time even when I flip the switch to 4x4. took apart the rear dif. and discovered the clutch pack with electronic solenoid attached to the front. I get it now...I have to ensure the solenoid is working to compress the pack. Thanks for posting this as I have been searching for days to validate what was in my mind. Great learning video!
Thank you. I am glad it was helpful
Love this tutorial. Thank you so much.
De años el mejor explicado video que he visto en UA-cam sobre estos temas , me distraía el estar buscando el botón para suscribirme excelente trabajo en esta clara explicación gracias desde CDMX.
Thank you!
Fascinating! Thank you, Professor Kelly!
Glad you enjoyed it!
@@WeberAuto My favourite channel! 👍🏻 I hope you and your family are well.
hi sir, the way u r discribing is very easy to understand, thanks for giving this type of great lessons....
+bala chandran Thank you for watching!
Now i know how. Great explanation, thank you so much sir. God bless you.
You answered EVERYTHING!!!.......Thank you!
Thank you!
What about when you getting noise from their what cause it
Well done, really informative. Subscribed right away.
Thank you!
Thank you for making this video and sharing it for free.
amrit351 Thank you for watching.
This clears up a lot of confusion thanks.
Thank you!
Wow...Thanks for your amazing explanation!
Thank you!
Thanks for another great explanation
+Kaktus Jack Thank You!
Knowledgeable and well explained, easy to understand and follow. You made this look easy. Heck with manuals, just come to this channel.
Thanks for watching
I love ALL your videos, you are doing great job!!
Thank you!
Great explanation! Thank you!
Beautiful explained
Excellent video! Well done. Thanks for your effort.
Thank you!
John watching this in 2021 I very much enjoy watching your videos I've learned and lot THANKS
You are very welcome. Thanks for watching
I have a 2002 Pontiac 4T60E that I have rebuilt, when I first start out it will shift once into second, then will seem as though it skips and goes into 3rd gear then will come back into 2nd gear, after watching all of Ur videos Iam sure U can help me diagnose this problem, I have asked several other people and haven't come up with a good answer,
Iam so impressed with Ur classes and would like to be a little younger so I could be enrolled in Ur classes since like I have stated I learn so,etching every time I watch one of Ur classes,
This auto is equipped with a 3,1 eng. And is a Grand Prix SE, during the overhaul of the Trans I replaced all the clutches and bands and seals and cleaned the valve body
Thank you for your very informative videos!
This is very similar yet very different to how Celica GT4 system works (particularity ST205 chassis). Interesting part is that unlike viscous/similar coupling at the rear differential the GT4 uses full central differential in the centre with a viscous centre, thus giving true all-time 4WD system with 50/50 torque split. This system in my opinion is far better than the typical crossover system.
Meanwhile Subaru system is even better in regards that it uses planetary gear set with mechanical LSD and electromechanical LSD (two separate units) for the centre differential, specifically the DCCD variant that comes in Impreza WRX STI.
I have/had pleasure owning both vehicles and I find very amusing when I go passed stuck crossover/SUV vehicles like RAV4 and similar on a beach (they seem to constantly switch between spinning a front wheel, and two diagonal wheels). I guess having LSD in front (excl. ST205) centre and rear with all time 4WD works much better than the gimmick system with viscous/electromechanical/hydraulic coupling that these crossover/SUV vehicles have.
Thanks for your great feedback! There are many variations of "AWD", most people do not know the differences.
Great video, thanks again
Great explanation professor!
great video as always!
Thank you!
What a wonderfully made video. Marvelous! :-)
Thank you
This was a great tutorial, kudos to your work, this video made my day, thanks man ❤️❤️. I always wondered how AWD works and here's the answer
Very much appreciated for this video. Liked and subbed. Was looking for exactly this!
Thank you!
Very informative video. Thank you. Helped me explain a lot to my son :)
Thank you! I am glad it was helpful
i realy do not know what to say , there is not a more confusing explanation to such simple concept , this man is genious in making it difficult
Thanks for watching anyway
so you get my point , thanks for reacting .
@@woodennecktie This video has over 200,000 views and only 60 dislikes (0.03%). As a professor of automotive technology, I understand that there are many different learning styles, levels of experience, and levels of knowledge. I made these videos for my college students who have limited knowledge and experience. I understand that someone who thinks they may already know how a certain system works may find my presentations boring or too basic.
So we have a different aprouch in whats basic and whats detail . Thats okay we teach crane operators, And the first thing we explain is the input and output of a system... Than we go into the details , sitting on a stool is not a way to explain subjects of any kind
@@woodennecktie I am in a wheelchair
Thank you you sir you explain it very well. Thanks once again.
Thank you!
These videos ar the best. It's also pretty neat to see that toyota is still using the same bolt pattern with the power transfer unit/transfer case. I have 1996 st205 and every GT-four before that had also the same bolt pattern. That ring and pinnion gear has shrunk alot compared to GT-four's.
Great video!
Thank you!
Such a great video!!! 👏👏👏
Thank you!
Thank you for best information
You are welcome
Very well explained.
Thank you very much
I bought a Ford police interceptor sedan (Taurus) and was curious how these systems worked, being fwd biased and such. Very informative.
Thanks for watching
Very informative. Enjoyed it, well done sir
Thank you!
I have a Renault Koleos, (Nissan X Trail AWD drive train) and I wondered how it worked... now I do :-)
Super explenation. Thankyou very much!
Thank you
Tank you for this video information
Thank you very educational!
Thank you!
Thanks for the video, it really has me appreciating just how awesome the symplicity of my Subaru XV Crosstrek's Subaru Symmetrical All-Wheel Drive, specifically, the Continuous AWD system that actually maintains a true mechanical connection between the front and rear differentials on manual transmission (technically a manual transaxle) models. Unlike most crossovers that have some sort of electronic system to manage front-to-rear torque distribution, the Continuous AWD of manual transaxle models has a simple viscous coupling center differential. Though some may consider this system quite crude, I'm very satisfied with its ability to react in demanding spirited driving conditions as well as off-road driving.
Thanks for your feedback!
Mantap kali bang pemjelasan nya...
thanks for this...
Thank you that was great...learned a lot..Professor you do a fantastic job! Decision now buy a Ridgeline with FWD or AWD!
Thank you
The content is great thanks
Masterful presentation. Seeking to bypass the was on murano.. I think I will start by disabling the Clutch Permanently.
Thank you!
WeberAuto Based on the information presented, I was able to save thousands by removing the drive shaft and eliminating AWD feature by taking the pinion gear from the transfer case. Ultimately the 2005 Nissan Murano's AWD capabilities are very pricey to repair so if you are not in need of all wheel drive start eliminating the cancer and save that money for the transmission God forbid! Thanks again for the awesome succinct video my friend!
Useful info
great information video
Thank you!
thank you somuch
Thank you!
Thank you!
Thank you very much!
Thank you!
I like the style used in the Honda Pilot or Acura MDX where the main Final Drive has 2 sets of Ring Gears, The secondary connects to a small Input shaft that goes to a Transfer Case with its own Ring and Pinion for the Propeller shaft.. Its lighter, stronger and both front axle shafts remain the same size..
Thanks for your feedback. I am not sure it is any lighter weight with the extra components inside the transaxle. The Honda system operates just like the system in this video; however, it uses different components to accomplish it. It still drives the rear driveshaft off the the transaxle differential case. The Acura systems with all of the variations of SH-AWD is also similar, but with a more advanced rear drive module for left and right rear wheel speed controls.
Excellent.... thank's
Thank you
Muito bom professor DEUS abençoe
good one...
Wow, had no idea thanks.
amazing, thank you
Thank you!
John, you are amazing!! I am a auto Teacher in Canada. The videos you make after hours when youth gone are are amazing. I am just wondering. Are you in a wheel chair? It doesn't matter if or not. Your knowledge blows me away. I am learning and love it. Peace....
+MonteSBC400 Thank you! Yes, I am in a wheelchair now. Muscular Dystrophy is slowly causing me to loose all my strength. Luckily I can still work in a field I love. Take Care.
Thank you sir !
Thank you!
Good teacher
Gotta see that final drive clutch pack....
Great video... I wish i lived close to your shop, you seem to know about about what you do, I have an issue with on AWD saturn vue that NONE of my local mechanics can figure out.
thanks for this
+Eng.jameel akel Thank you for watching!
An advantage of the overdriven propeller shaft is that it can be thinner to handle a given amount of torque from the transaxle.
SUPERBBB!!!
hellow Mr killy l am wathing moste of your shows I like it so thank you .
.sorry bad English...
مرحبا استاد حون كلي انا اتابع معظم شروحك واحبها شكرا too mutch
+خالدمحمد الرحيلي Thank you for watching!