Another broken Torsen carrier
02-13-2019, 09:20 PM
#1
Another broken Torsen carrier Went to move my wifes 01 WS6 in the snow and only one tire turns in the rear................this is like the 5th torsen carrier we broke over the years, mostly stock A4 cars too. These dam carriers always break on a 1-2 shift WOT. I may just drive it till it craps out completely. Anyone ever drive a broken one like this for a long period of time? I think this one has been broken for quite a while.
02-15-2019, 08:36 PM
#3
Torsen Torque Bias The Torsen needs the torque reaction from the low traction wheel to use its torque bias to drive the high traction wheel. A posi-type rear does this with internal springs and clutches. If you have a very low traction scenario on one wheel, you may not get enough torque reaction to drive the other.
The below are excerpts from Torsen's website: https://torsen.com/ask-torsen-torque...nal-questions/
"The simplest way to conceptualize torque bias ratio (TBR) is to think of it as a traction ratio. This represents how much difference is allowed from one side to the other; if the TBR level is exceeded, the differential will “open” and allow spin or differentiation to occur. If the ratio of traction from one side to the other is less than the TBR, the differential will remain locked up. For example, if the TBR is 4:1, differentiation (or spin) will not happen unless your low-traction tire has less than a ¼ of the traction that the high-traction tire has.
Another way to think about TBR is this: it also represents the maximum distribution ratio of torque from side to side. The high traction tire receives (up to) whatever amount the low-traction side can sustain, multiplied by TBR. So, T(high) = T(low) X TBR. This does necessarily mean that the Torsen requires some amount of reaction torque on both outputs to be able to act against. This is typically the result of tire contact with the ground.
In extreme situations, such as when a tire is lifted off the ground completely, that zero X TBR is still = zero. So, yes, in that case, the Torsen is limited."
Hope this helps -Jim
The below are excerpts from Torsen's website: https://torsen.com/ask-torsen-torque...nal-questions/
"The simplest way to conceptualize torque bias ratio (TBR) is to think of it as a traction ratio. This represents how much difference is allowed from one side to the other; if the TBR level is exceeded, the differential will “open” and allow spin or differentiation to occur. If the ratio of traction from one side to the other is less than the TBR, the differential will remain locked up. For example, if the TBR is 4:1, differentiation (or spin) will not happen unless your low-traction tire has less than a ¼ of the traction that the high-traction tire has.
Another way to think about TBR is this: it also represents the maximum distribution ratio of torque from side to side. The high traction tire receives (up to) whatever amount the low-traction side can sustain, multiplied by TBR. So, T(high) = T(low) X TBR. This does necessarily mean that the Torsen requires some amount of reaction torque on both outputs to be able to act against. This is typically the result of tire contact with the ground.
In extreme situations, such as when a tire is lifted off the ground completely, that zero X TBR is still = zero. So, yes, in that case, the Torsen is limited."
Hope this helps -
02-16-2019, 10:06 AM
#4
TECH Senior Member
iTrader: (96)
Join Date: Aug 2007
Location: Turnin' Wrenches Infractions: 005
Posts: 24,241
Likes: 0
Received 79 Likes
on
70 Posts
I know they are limited by design on how much power they can transfer. Also, laying stripes on pavement vs a snowy driveway load the posi differently and make it respond different.
02-16-2019, 04:32 PM
#5
The tire that spun was on ice, the other that wouldn't move was on pavement. A few winters ago it was stuck in snow ruts in the driveway from sitting out after a snow storm but both tires were on snow. Both dug in and turned and the car moved.
Now a few years back we had TA that refused to move in the snow, only one tire would spin and it had the torsen diff. That one was broken because it also only spun one tire out on dry road driving too. After the dealer replaced the torsen it worked in the snow too.
I drove the car today, the roads are very dirty gravel at intersections etc. Its definitely working because it pulls with both tires on the gravel etc. I can also feel how the car reacts as I make hard turns pulling out onto main roads, you can feel each tire digging in moving the car without spinning the tires. When the torsen was broken in the other cars it would spin the one tire in gravel and just sit there barely moving as you tired to pull out making a turn onto a main road.
Also if I stand on it from a stop light the car moves out hard and straight, If it was broken only driving one tire it would go up in smoke.
Now a few years back we had TA that refused to move in the snow, only one tire would spin and it had the torsen diff. That one was broken because it also only spun one tire out on dry road driving too. After the dealer replaced the torsen it worked in the snow too.
I drove the car today, the roads are very dirty gravel at intersections etc. Its definitely working because it pulls with both tires on the gravel etc. I can also feel how the car reacts as I make hard turns pulling out onto main roads, you can feel each tire digging in moving the car without spinning the tires. When the torsen was broken in the other cars it would spin the one tire in gravel and just sit there barely moving as you tired to pull out making a turn onto a main road.
Also if I stand on it from a stop light the car moves out hard and straight, If it was broken only driving one tire it would go up in smoke.
02-18-2019, 08:15 PM
#6
The tire that spun was on ice, the other that wouldn't move was on pavement. A few winters ago it was stuck in snow ruts in the driveway from sitting out after a snow storm but both tires were on snow. Both dug in and turned and the car moved.
Jim
02-19-2019, 04:52 PM
#7
TECH Senior Member
iTrader: (96)
Join Date: Aug 2007
Location: Turnin' Wrenches Infractions: 005
Posts: 24,241
Likes: 0
Received 79 Likes
on
70 Posts
as weird as this sounds it actually works. Honda front diffs (atvs) are notorious for 3 wheel pulls in mud. Applying a little front brake makes the stuck wheel pull every single time.
Trending Topics
02-22-2019, 11:58 AM
#8
LOL on the brake trick, its the 1st thing I tried when it wouldn't move and it didn't help. That's why I assumed the torsen was broken........this still puzzles me. Only thing I can think of is somehow the gearing inside the torsen jams up enough to work moving down the road.