[sudev]

Rishi trail blazing is always fun. Good company makes it excellent. The weather made it superb. This is further enhanced when you have ace photographers capturing it all with their lenses:

[HillBilly]

Originally Posted by Endeavour333

Just 1 question, how did only 1 of the Endy's front and rear wheels spin? were the other 2 not spinning? Since the Endy has a limited slip diff at the rear shouldn't it have locked the differential when it sensed too much difference in rotational speeds of the rear wheels which would then result in all 4 wheels locked and spinning at the same rate?

Hi Endeavour333!

Yes, this was what made me really confused. I was in 4WL and the diff wasn't locking. In the older Endy models, there is a switch on the dash that you had to put on that would lock the diff, but in the new auto model there isn't any switch so you have to rely on the Borg Warner transfer case to do it's job and sense the situation. Unfortunately it didn't in this case! But it sure was a learning experience!

"New A/T tyres" are my immediate requirement. the standard MRF ZVTS' aren't for this type of terrain.

[phamilyman]

DQ: What interior cleaner chemical etc do you all use after such a drive? or just let the A.S.S do its job?

[sudev]

A water jet on ramp is sufficient. The unreachable slush will stick on and slowly drop off as it dries.

Net damage to GV after the drive:
One rubber hanger loose on rear exhaust. Slid it back and all's well.
The front bumper was "dented" by a stout sapling. A punch from inside and plastic is back in shape.
The front bumper locks opened up while going through prickly under bush. Snapped them back.
Scratches on paint work. A good wax job hides most of them. But hey why buy a SUV if you want to keep it pristine clean??

[sudev]

Originally Posted by phamilyman

....this is a parking lot picture - itni mud toh sohna road pe mil jaati hai. get us more action shots

Hope your expectations were met ji??

[phamilyman]

Nyah. I wanted more. This seemed tamer compared to your previous jaunts - even in pictures! on an absolute level, yes, quite nice, but Not your standard

[sudev]

@phamilyman : Nice one. Turning it in to a self competition are we? You turn up next time and then we will discuss.

[Samurai]

Originally Posted by Endeavour333

Just 1 question, how did only 1 of the Endy's front and rear wheels spin? were the other 2 not spinning? Since the Endy has a limited slip diff at the rear shouldn't it have locked the differential when it sensed too much difference in rotational speeds of the rear wheels which would then result in all 4 wheels locked and spinning at the same rate?

Originally Posted by sudev

The owner - Kevin - was also under the same impression that the rear has LSD and it should not have been stuck. We tried it again and again just make sure that there was no special "switch" or setting to engage LSD. So either LSD was not working or not available.

May be I can explain a little before experts pitch in. The torque sensing LSD is different than clutch type LSD or viscous type LSD. The clutch type or viscous LSD will behave like you expect, more the difference in speed, more the torque transfer to the wheel with grip.

But the torsen (torque sensing) LSD works on torque multiplier principle. If one wheel has less traction, it needs less torque to rotate, this lesser torque is multiplied and sent to the other wheel with grip. However, if one wheel no grip at all and is free-spinning, the torque required to rotate it will be near zero. Guess what the torque multiplier gets out of that? Almost near zero. Therefore, in a torsen LSD setup you do need some grip in the slipping wheel for useful torque transfer to the other wheel. If you have free-spinning wheel, you are indeed stuck. You can try braking and get some resistance from free-spinning wheel, this enables better torque transfer.

Endeavour has torsen LSD in the rear, same goes for Fortuner and Grand Vitara in the center.

This is not a new discussion, this has been discussed before:

https://www.team-bhp.com/forum/4x4-e...tml#post661195 (Report - Offroad Training Day at Kelambakkam Quarry)

See description of H mode here: https://www.team-bhp.com/forum/4x4-t...ml#post1450245 (Center Differential and LSD in SUVs)

[sudev]

Okay so Samurai what you are saying is that one could have gotten out of the situation by using, say, handbrake on the rear wheel to get torque transfer to the other rear wheel?? But the brake would have applied to that one also. Would it not???

[Samurai]

Yes it would, but the torque will be different. Due to brake resistance, the spinning wheel will now need more torque to overcome the braking force, the other wheel will get X times that and can overcome the same braking force lot easily.

The braking should be gentle, don't fully stop the wheel rotation.

[funmaniac]

Some more pictures of the event:

[sudev]

Originally Posted by Samurai

Yes it would, but the torque will be different. Due to brake resistance, the spinning wheel will now need more torque to overcome the braking force, the other wheel will get X times that and can overcome the same braking force lot easily.

The braking should be gentle, don't fully stop the wheel rotation.

@HillyBilly : SO when is this theory going to get tested?? ;-)

[Endeavour333]

Originally Posted by HillBilly

Hi Endeavour333!

Yes, this was what made me really confused. I was in 4WL and the diff wasn't locking. In the older Endy models, there is a switch on the dash that you had to put on that would lock the diff, but in the new auto model there isn't any switch so you have to rely on the Borg Warner transfer case to do it's job and sense the situation. Unfortunately it didn't in this case! But it sure was a learning experience!

"New A/T tyres" are my immediate requirement. the standard MRF ZVTS' aren't for this type of terrain.

I'm getting myself new AT tyres too either BF Goodrich TA/KO or Yokohama Geolanders - Size 265/70/16 or 265/65/16. Cant wait for my garage guy to source them for me. I've tried looking but its nearly impossible for me to find that size without the right contacts. Will let you know if when I get some. Getting them most likely from coimbatore apparently.

Yes I expected that the LSD would kick in but just read up on the Torsen LSD and now it makes sense why that happened. The Torsen LSD works well on the road when both wheels will always have some traction but not so good when a wheel is in the air or really slippery slush. Cant wait to try out Samurai's trick of applying the brake to get power to the other wheel!

By the way, any comments on how the Endeavour performed in such harsh conditions? Was it much worse than the Pajero? Better than the others? Would be interesting to hear. If I was anywhere near Gurgaon I would have DEFINITELY come to this outing! I'm so jealous of you all that got to go. Just hoping something like this happens in the south too.

Originally Posted by Samurai

Yes it would, but the torque will be different. Due to brake resistance, the spinning wheel will now need more torque to overcome the braking force, the other wheel will get X times that and can overcome the same braking force lot easily.

The braking should be gentle, don't fully stop the wheel rotation.

Samurai, thank you so much for sharing your knowledge. I have a greater understanding of y car now and cannot wait to try this technique out at some point.

[Raosaheb Desai]

Interesting one.
Hope one day I join you if arranged near to Mumbai.

[nilanjanray]

Lovely narration Sudev.

Any similar event happening in the South, I am game. Would be good to finish with overnight stay in a picturesque location and then drive back next morning.