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yt110
7th April 2010, 12:47 PM
Will I be doing any damage to internals eg. cv's or steering box by adjusting my lockstop? I have disco rims with 235/85x16 on my county and there is plenty of room between the tyre and lower arm so how far can I adjust the locks in? Does having more lock load up cv's more when on full lock?

isuzurover
7th April 2010, 01:16 PM
The practical limit is when the tyres start to rub the radius arms.

It is likely that having more lock will increase the chances of breaking a CV - but only during hard use offroad.

I think Sam from haultech used to add lockstops to the rear of the swivels as well. His theory was that there is enough flex in the steering/axles that the inside wheel (which is not against a stop) can be forced to turn tighter, and can overstress a CV.

If you have standard axles though, no need to worry about the CVs - the 10-spline inners will break first.

yt110
7th April 2010, 02:03 PM
If you have standard axles though, no need to worry about the CVs - the 10-spline inners will break first.[/QUOTE]

I have keiths axles and fine spline truetrac

isuzurover
7th April 2010, 03:59 PM
I have keiths axles and fine spline truetrac

Ahh, then you do have to worry. However the truetrac is fairly easy on the CVs as when you lift a wheel it send all the drive to the wheel that is off the ground.

So as long as you don't come down hard with one front wheel spinning, or use the brake agressively to force the wheel on the ground to drive, then the CVs should have a long life.

Bush65
7th April 2010, 06:34 PM
... However the truetrac is fairly easy on the CVs as when you lift a wheel it send all the drive to the wheel that is off the ground.

...
If only that was so.

The way the torque bias of truetracs work is; when one wheel has low traction it will send more torque to the wheel with most traction. The torque sent to the wheel with most traction is up to the torque at low traction wheel times the bias ratio - sorry I can't remember the bias ratio.

If the low traction wheel is in the air it has zero torque and so does the one with more traction (0 x bias ratio = 0).

If you dab the brakes some torque will then go to the other wheel with traction.

Edit: true tracs work very well with traction control

1103.9TDI
7th April 2010, 06:39 PM
Adjusting the offset of your Disco rims will help, a bit of mucking around though....

isuzurover
7th April 2010, 08:21 PM
If only that was so.

The way the torque bias of truetracs work is; when one wheel has low traction it will send more torque to the wheel with most traction. The torque sent to the wheel with most traction is up to the torque at low traction wheel times the bias ratio - sorry I can't remember the bias ratio.

If the low traction wheel is in the air it has zero torque and so does the one with more traction (0 x bias ratio = 0).

If you dab the brakes some torque will then go to the other wheel with traction.

Edit: true tracs work very well with traction control

Excuse me for being dense John...

When you have a truetrack and lift a wheel completely off the ground, the wheel off the ground will spin and the wheel on the ground will not turn (like an open diff). I cannot see how the wheel off the ground can have no torque??? And you are saying the wheel on the ground has torque, but not enough to turn?

Bush65
8th April 2010, 11:16 AM
Excuse me for being dense John...

When you have a truetrack and lift a wheel completely off the ground, the wheel off the ground will spin and the wheel on the ground will not turn (like an open diff). I cannot see how the wheel off the ground can have no torque??? And you are saying the wheel on the ground has torque, but not enough to turn?
My previous post was worded poorly.

The torque that can be applied to any wheel depends on how much traction the wheel has. If a wheel is spinning in the air the torque will greater than zero, because of rotational inertia bearing and seal friction. But it will be very low.

The torque that the truetrac can send to the wheel on the ground can not exceed bias ratio x torque at wheel in air - not enough to be useful (similar to having an open diff).


The Torsen differential is a purely mechanical device; it has no electronics, clutches, or viscous fluids. The Torsen (from Torque Sensing) works as an open differential when the amount of torque going to each wheel is equal. As soon as one wheel starts to lose traction, the difference in torque causes the gears in the Torsen differential to bind together. The design of the gears in the differential determines the torque bias ratio. For instance, if a particular Torsen differential is designed with a 5:1 bias ratio, it is capable of applying up to five times more torque to the wheel that has good traction. These devices are often used in high-performance all-wheel-drive vehicles. Like the viscous coupling, they are often used to transfer power between the front and rear wheels. In this application, the Torsen is superior to the viscous coupling because it transfers torque to the stable wheels before the actual slipping occurs. However, if one set of wheels loses traction completely, the Torsen differential will be unable to supply any torque to the other set of wheels. The bias ratio determines how much torque can be transferred, and five times zero is zero. The AM General Hummer (or HMMWV) uses Torsen differentials on the front and rear axles, and the owner’s manual proposes a novel solution to the problem of one wheel losing traction: Apply the brakes. By applying the brakes, torque is applied to the wheel that is in the air, and then five times that torque can go to the wheel with good traction. The Detroit TrueTrac torque biasing ranges from 2.5:1 to 3.5:1

yt110
8th April 2010, 02:37 PM
I have turned the lockstops in 2 turns,still have clearance between the tyre and the radius arm and have reduced the turning circle by 1 metre.
Jim.

isuzurover
8th April 2010, 03:02 PM
My previous post was worded poorly.

The torque that can be applied to any wheel depends on how much traction the wheel has. If a wheel is spinning in the air the torque will greater than zero, because of rotational inertia bearing and seal friction. But it will be very low.

The torque that the truetrac can send to the wheel on the ground can not exceed bias ratio x torque at wheel in air - not enough to be useful (similar to having an open diff).

Ah, cheers - crystal clear now.

So, in layman's terms, it is unlikely you can break a CV with a torque biasing diff in that situation, unless one wheel was wedged almost solid and you tried to use the brakes to get it to turn.

Bush65
9th April 2010, 09:41 AM
...

So, in layman's terms, it is unlikely you can break a CV with a torque biasing diff in that situation, unless one wheel was wedged almost solid and you tried to use the brakes to get it to turn.
It won't be due to having a torque biasing diff.

I have truetrac diffs front and rear in my disco, but with Maxi-drive axles and County cv's. My disco sees mild off road use only.