Preference, locker front or rear ?

[AJ120 Out of control poster! Find all posts View Profile Close AJ120]

Is that when the gearbox is in the back end, like a 928 Porsche?

F*#%*|G auto correct Manual gearbox!

Cheers Andrew

[baders Junior Member Find all posts View Profile Close baders]

I would ring them back and ask to speak to someone else ,,, The 90 and 120 use the same rear diff...

I tried really hard to get more info on why it is supposedly "incompatible", but got nowhere. As to why it would be so with a manual Prado and OK with say a manual 100 series is beyond me. I got the impression the chap really didn't give a rats. Both the 90 and 120 series are listed as "Most" in compatibility on their web site; http://www.4wdsystems.com.au/index.php?id=70

[baders Junior Member Find all posts View Profile Close baders]

OK, after some research in our own archives and elsewhere it appears as if there could be a problem with Lokkas and manual transmission backlash. I'm betting that there have been a few failures early on and now the distributors want nothing to do with anything but autos. No problem with that, but why the evasiveness ? Surely just coming out and saying it would be better ? Lost any business from me I'm afraid.

[baders Junior Member Find all posts View Profile Close baders]

Only other thing I 'd be considering is how much longer do you intend to keep the vehicle? Worth throwing that locker into a 120 or even 150?

Cheers,

Hey SS. This one has been in the family since 1997, and my plans are to keep it a good while yet.

[adrian5800 Advanced Member Find all posts View Profile Close adrian5800]

You can fit a Detroit locker in the the rear of a manual prado, lunchbox lockers like Lokka aren't anywhere near the strength or reliability of a Detroit.


Ades

[baders Junior Member Find all posts View Profile Close baders]

I think I have decided to go with a Detroit Tru Trac LSD. For my range of driving and after the mountains of research done, I don't believe I need a locker in the rear. The Tru Tracs are allegedly much more capable than the standard Toyota LSD, whilst not having the full locking ability of the lockers, it is around half the price. If my habits get more extreme in the future, I can always install a selectable locker in the front.

[adrian5800 Advanced Member Find all posts View Profile Close adrian5800]

I think I have decided to go with a Detroit Tru Trac LSD. For my range of driving and after the mountains of research done, I don't believe I need a locker in the rear. The Tru Tracs are allegedly much more capable than the standard Toyota LSD, whilst not having the full locking ability of the lockers, it is around half the price. If my habits get more extreme in the future, I can always install a selectable locker in the front.

You can get a tru trac to lock up, if you have a wheel in the air the idea is to dab on the brakes to provide enough torque to the lsd to bind up the worm gears. The only problem is by then you have lost all forward momentum. A locker won't suffer from this.

Don't take this as criticism of your decision, a tru trac is miles ahead of the standard toyota (non) lsd..




Ades

[adrian5800 Advanced Member Find all posts View Profile Close adrian5800]

OK, after some research in our own archives and elsewhere it appears as if there could be a problem with Lokkas and manual transmission backlash. I'm betting that there have been a few failures early on and now the distributors want nothing to do with anything but autos. No problem with that, but why the evasiveness ? Surely just coming out and saying it would be better ? Lost any business from me I'm afraid.

Because that would be admitting that their product is inferior in the strength department..

[MelbournePark Member Find all posts View Profile Close MelbournePark]

You can get a tru trac to lock up, if you have a wheel in the air the idea is to dab on the brakes to provide enough torque to the lsd to bind up the worm gears. The only problem is by then you have lost all forward momentum. A locker won't suffer from this.

Don't take this as criticism of your decision, a tru trac is miles ahead of the standard toyota (non) lsd..




Ades

The problem with the 90 ( I have a 150 now but have not yet sold my 90 which I've had since 1996) is that every cent you spend on the 90 is down the drain - you won't get it back when you sell it. Hence my reluctance give my 90 away.

Could you try the crappy hand brake on the back wheels when climbing and just forget about it and get the elocker to do its thing?

The 90 is very light compared to 120s etc. so it can handle off road difficult terrain better. Weight is not an advantage off road.

But, IMO, if you keep the 90 one or two years, then the full e-locker would be worth it. Peace of mind and lack of worry etc., and when around other 4WDs, they might look down on your 90 series with its lack of technology ... but having the full locking rear diff, and its lighter weight, your ego can be protected and you can feel very comfortable and perhaps superior inside knowing that your's can go uphill a very long weigh. I suspect a 90 with a locked rear diff going up something steep, would outperform later Prados due to its lighter weight. My V6 90 now gets in the 12s per 100Km on the highway with a rack and tent on the roof at the speed limit (with high octane fuel) despite its 2" lift, alloy roo bar and tow bar and camp gear water etc inside. The only noisy thing on the highway for our 90 is the mirror wind noise. I am thinking if you consider the extra cost of a 120 or 150 ... the full e-locker would be worth it. - if your going to some expense, why compromise?

[MelbournePark Member Find all posts View Profile Close MelbournePark]

In the photo below the Prado only has a rear locker and clearly the front wheel is well of the ground but is not spinning. This is because it also has a centre diff lock which means the front axle can't spin faster than the rear. So lifting a front wheel is not such a big deal with the rear and centre diff locked.




Cheers Andrew

Sorry Andrew, but I think that the front wheel will spin in the situation you describe above.

Firstly, the rear and centre is locked so the driveshaft speed is operating at the same speed to both front and rear axles - as you described.

However, IMO and with respect, if the front wheel lifts, then all the power from the forward driveshaft will go to that wheel which is clear off the ground ie the non gripping wheel. Hence the wheel on the ground will not get any power.

Perhaps the driver of that vehicle applied some brakes to limit the front wheel spin?

I have wondered how useful it would be if hand brakes on a Prado could operate the front wheels ... then you could put the handbrake on if the front lifted on an open diff Prado (as most of them are). I guess it would cost brake pads ... my old SAAB 99 turbo had its hand brake on the front wheels ...

[120D4D Avid PP Poster! Find all posts View Profile Close 120D4D]

Sorry Andrew, but I think that the front wheel will spin in the situation you describe above.

Firstly, the rear and centre is locked so the driveshaft speed is operating at the same speed to both front and rear axles - as you described.

However, IMO and with respect, if the front wheel lifts, then all the power from the forward driveshaft will go to that wheel which is clear off the ground ie the non gripping wheel. Hence the wheel on the ground will not get any power.

Perhaps the driver of that vehicle applied some brakes to limit the front wheel spin?

I have wondered how useful it would be if hand brakes on a Prado could operate the front wheels ... then you could put the handbrake on if the front lifted on an open diff Prado (as most of them are). I guess it would cost brake pads ... my old SAAB 99 turbo had its hand brake on the front wheels ...

Not quite right MP. (that is my rig with its wheel up and the centre and rear diffs locked!)

While you are correct that the front LH wheel will not be getting any power in this position, the RH wheel in the air can only turn as fast at the rear wheels (CDL + RDL engaged). There is no opportunity to limit the wheel spin as such.

Perhaps technically the RHS wheel is 'spinning' in the air, but out on the tracks its really just 'turning' the same speed as the others...

[AJ120 Out of control poster! Find all posts View Profile Close AJ120]

Not quite right MP. (that is my rig with its wheel up and the centre and rear diffs locked!)

While you are correct that the front LH wheel will not be getting any power in this position, the RH wheel in the air can only turn as fast at the rear wheels (CDL + RDL engaged). There is no opportunity to limit the wheel spin as such.

Perhaps technically the RHS wheel is 'spinning' in the air, but out on the tracks its really just 'turning' the same speed as the others...

Beat me to it, I have been back to that same spot and tested this theory and with rear and centre diff locked the front wheel doesn't spin. As Michael says, whether the front is really driving is another story, which is why they also make front lockers.

Cheers Andrew

[Anth120playdo Banned Find all posts View Profile Close Anth120playdo]

Sorry Andrew, but I think that the front wheel will spin in the situation you describe above.

Firstly, the rear and centre is locked so the driveshaft speed is operating at the same speed to both front and rear axles - as you described.

However, IMO and with respect, if the front wheel lifts, then all the power from the forward driveshaft will go to that wheel which is clear off the ground ie the non gripping wheel. Hence the wheel on the ground will not get any power.

Perhaps the driver of that vehicle applied some brakes to limit the front wheel spin?

I have wondered how useful it would be if hand brakes on a Prado could operate the front wheels ... then you could put the handbrake on if the front lifted on an open diff Prado (as most of them are). I guess it would cost brake pads ... my old SAAB 99 turbo had its hand brake on the front wheels ...

You are correct.
The front driveshaft & pinion is locked to the centre diff, not the front wheels!
If there is no locker in the front, in that cituation there is NO DRIVE to the front, it's not possible.
It's an open diff, That's why they sell front & rear lockers & not just the front.
In that cituation, if you had some smooth momentum, a rear locker & good traction it can appear as if they can't spin or like they are helping, in fact it's the rear, with all the flex & traction doing the pushing.
Don't want to argue, it just sounds like some have been convinced the front in that pic is helping, but it's not.
It's not possible for the front driveshaft to spin faster than the rear.
You need to have traction on both fronts for it to pull you along, if you don't have it locked.
The front wheels are able to turn at different speeds, eg, one could stop & the other can spin.

I hope that helps.

[Anth120playdo Banned Find all posts View Profile Close Anth120playdo]

I recommend rear locker, because it adds to the strength of the solid rear axle. It can be used for entire climbs without being concerned about CV failures or steering.

A front locker will give you the most traction for your dollar (given you'll still have a rear LSD), but at the risk of CV failure and irregular steering.

It may also depend on what terrain you drive, and in your case, I'd still say rear.

Since I have both, I use rear most times, and add the front only in extreme situations (typically big rock steps).

That's great advise, Well said.

I would add if your c/v angles are not too high, the genuine c/v's are very strong, usually it's the angles + locker that pushes it over it's limit.

[Corigator Avid PP Poster! Find all posts View Profile Close Corigator]

Not quite right MP. (that is my rig with its wheel up and the centre and rear diffs locked!)

While you are correct that the front LH wheel will not be getting any power in this position, the RH wheel in the air can only turn as fast at the rear wheels (CDL + RDL engaged). There is no opportunity to limit the wheel spin as such.

Perhaps technically the RHS wheel is 'spinning' in the air, but out on the tracks its really just 'turning' the same speed as the others...

in this situation, the time the front wheels would be pulling their load would be if the rears are both slipping. If they slip the free front wheel will rotate more quickly and no power would be going to the one front wheel on the ground. Only a front locker would help then.