SLIP TEST - Volvo V90 CC AWD vs Volvo XC70 / V70 XC AWD -

[@dimitu_]

Damn. On last test I was like "c'mon, c'mon, you can do it!"

[@PreBCFan1]

oh, I have the XC70 2007 model and I love that comparison, since you have a video of the 2006 or 2007 model as well. Ty sm. Great video again, was so happy to so it in my alerts

[@4x4.tests.on.rollers]

Thank you!

[@Softroader]

Not bad for the Grandma with her viscous coupling. After that, the problem of the only rear wheel is not a surprise. 1/ The torque limit of the viscous coupling. 2/ The Volvo TRACS traction control was originally designed to work only on the front wheels. On the previous Awd transmission, there was even an Eation G80 (now called MLocker) self-locking differential in the rear axle.

[@4x4.tests.on.rollers]

I'm wondering if there is any car with visco which can pass such test. That would require some twisty traction control tuning, keeping the front axle overspeeded and braking rear wheel to equalise the torque on both rear wheels.

[@Softroader]

@@4x4.tests.on.rollers You would already need a visco with a high torque capacity. Again, traction control doesn't really transfer torque. It creates a resistance that "simulates" grip. As you say, it equalises the torque as it does not change the mechanical torque distribution. So you need a lot of torque transfer capacity at the visco to still have enough on the one adherent wheel. But the torque transfer variability of a visco is much lower than that of a multi-plate clutch. This would imply a very rigid visco even without a difference in speed between the axles... Not sure if the rest of it follows. There are adaptations, for example, of the visco on VW Transport Syncro (especially T4) with higher torque values... except that the modification is only recommended for vehicles that are exclusively used off-road.

[@4x4.tests.on.rollers]

@@Softroader That's what I am wondering. I think that visco torque capacity is enough for that as it easily pushes the car when front wheels do not have grip or when there's a diff lock (three roller test). Obviously torque value must be higher if there's an open diff behind the visco, probably doubled, but the system would need to keep the speed difference between front and rear and find the "hump moment" to correlate it with brake intervention on one wheel. I don't think that any manufacturer would be interested in doing that. Haldex system has easier task - it increases the pressure up to the moment when car moves.

[@Trades46]

The old viscous coupling was good up until the 3 wheels on roller test, where it is clear that the Haldex unit is far superior.

[@okaythisisfuckingrid]

wait, from 2006 the XC70 had a Haldex unit, I thought?

[@nigeltoon1848]

@@okaythisisfuckingridIt does.

[@EDREdr-zh6nk]

So far I have been behind the wheel of many different types of vehicles. For 30+ years of experience I drove over 1 000 000 kms. I drove on asphalt, gravel, ice, snow, mud etc. I have never, and I mean never ever had to drive on rollers...

[@4x4.tests.on.rollers]

@@EDREdr-zh6nk Good for you 👍

[@appelsapman434]

I wonder if P80 platform (850, S/V70 AWD/XC) would do better on the last test because they have a rear locking differential.

[@4x4.tests.on.rollers]

With rear locking diff they would pass the last test easily.

[@LawatheMEid]

I liked the idea of this channel, would you please add few data for every test like r.p.m., fuel consumption and time to achieve the solo test. I suggest in this case to slice the screen vertically by ratio 2:3 .. the 2/3 would be sliced horizontally for as you done before, and the 1/3 for more camera view for what i had mentioned. Thanks

[@4x4.tests.on.rollers]

Thanks, we did it a few times, unfortunately it makes the test very complicated.

[@LawatheMEid]

@@4x4.tests.on.rollers you are right i saw them but there were lot of precise data, but 2 or 3 data will be less complicated more attracting.

[@luigivm]

V70 is Visco or Haldex? (Thogh 2001 models was Visco)

[@4x4.tests.on.rollers]

Visco.

[@martinsvensson6884]

4:15 It would be very interesting to know what the system is thinking here.... the "reasoning"...

[@4x4.tests.on.rollers]

That's actually easy to guess - as TC is only on front axle, it's thinking that everything is fine. Or it's not thinking at all as "everything is fine".

[@martinsvensson6884]

@@4x4.tests.on.rollers Wow.. more retarded than even I would have thought :) But nothing surprises me anymore. They already must have ESP on that car... so virtually 0 reason not to make it work on the rear axle also. Its not like there is less chance that a rear wheel loses traction than front.

[@4x4.tests.on.rollers]

@@martinsvensson6884 Not sure about ESP, there were cars equipped with TC but no ESP. Besides - I don't know present norms but some years ago, norms were saying that ESP on front is enough cause the point is to correct the "dangerous" oversteer, no worries about understeer... Other thing about TC is that it is not that simple to combined it with differential placed behind the visco coupling.

[@martinsvensson6884]

@@4x4.tests.on.rollers Cant imagine Volvo didnt have ESP on that car though... 4 wheel ESP was standard on all MB:s from -99...

[@4x4.tests.on.rollers]

@@martinsvensson6884 I don't know. There was no button, no menu, if ESP was there, then always on.

[@kordaxmint533]

I was right when I said that "new ones are even better".

[@aaronbarkus6458]

The wheels are clearly finding grip on these rollers, this test is not set up correctly nor are the rollers properly maintained i would guess

[@4x4.tests.on.rollers]

How did you came up with such a conclusion?

[@mateuszzebytomia]

V90cc nie ma najlepszego napędu. Zimą nie mogłem wyjechać z oblodzonego parkingu w górach. Wstydu się najadlem.

[@4x4.tests.on.rollers]

Volvo bardzo dobrze konfiguruje haldexy, więc dziwna sprawa. A ktoś inny mógł wyjechać?

[@mateuszzebytomia]

@@4x4.tests.on.rollers akurat w tym momencie, nie zwracałem na to uwagi, ale wyglądało to tak, że kręciło się tylko jedno koło a reszta stała w miejscu.

[@4x4.tests.on.rollers]

@@mateuszzebytomia To sugeruje uszkodzenie, sprawny układ nigdy tak nie działa.

[@mateuszzebytomia]

@@4x4.tests.on.rollers to ciekawe bo mialem nie raz do czynienia (w samochodach z dolaczanym napędem) z sytuacją, że w momencie zawisniecia jednego koła bądź jego poślizgu, tylko ono się kręciło a reszta stała. W związku z tym nieraz trzeba było samochód np rozchustac, lub dociazyc żeby po odzyskaniu przyczepności auto ruszyło. Zawsze mnie to dziwiło, bo gdzie tu sens dolaczanych napędów 4x4? I wydawało mi się że tylko blokada mechanizmu roznicowego jest w stanie rozwiązać problem (która mają tylko prawdziwe terenówki niestety).

[@4x4.tests.on.rollers]

@@mateuszzebytomia Sytuacja, w której będzie się kręcić tylko jedno koło może wystąpić tylko przy napędzie stałym opartym o trzy otwarte mechanizmy różnicowe, nie wspomagane żadną elektroniką. Sprawny napęd dołączany zawsze będzie w takiej sytuacji kręcił dwoma osiami, czyli min. jednym kołem na każdej osi. I to ma wspomóc kontrola trakcji, aby układ kręcił czterema kołami, trzeba tylko trzymać gaz i pozwolić jej działać. Nie bujać, nie pompować gazem etc.

[@JurisKankalis]

No Haldex. Just quattro. No xDrive. Just quattro. Why? Lift all of them on a carlift - inspect the power delivery path - and you'll understand why. Thanks for the video - greetings from Latvia.

[@4x4.tests.on.rollers]

Power delivery path is basically the same for all of them, including majority of present quattro models. Greetings from Poland!

[@4x4.tests.on.rollers]

@@InternetListener XC70 with haldex can make it: kzbin.info/www/bejne/mZnIn5Wblsunb5I

[@4x4.tests.on.rollers]

@@InternetListener We did test more cars with haldex 1 & 2, there was Audi TT, Skoda Octavia Scout, they passed all tests. XC70 had haldex 3 (never used in VAG). If I remember well - the only car with haldex 4 that didn't pass the last test was the A3, with haldex 5 - Tiguan and T6. I think all others did pass.

[@FIRST465]

Bro thinks he is on dyno

[@4x4.tests.on.rollers]

Who?