39 replies to this topic

[StephenSLR]

With a car like a commodore where they don't suffer anything like the weight transfer issues on the rear end they will work fine as you have similar weight over both rear wheels. With a weight transferring bastard like a Torana, they will be shit and will act much more like an open centre.

Are you talking about the clutch LSD or the Hydratrac acting more like an open centre?

Also can you explain weight transferring, does a V8 Commodore have less than a V8 Torana?

s

Edited by StephenSLR, 28 October 2008 - 07:03 PM.

[REDA9X]

Old topic, but would I be correct in thinking that with a Hydratrac, unlike a normal LSD, when you jack the car and spin one wheel, the other won't spin?

Mine has been chattering it's arse off (basically like a locker). I went to Holden they gave me an additive, but it's still chattered until yesterday morning when there was a loud bang in the back. It's no longer noisey or chattering, but I jacked it and spun a wheel and the other didn't spin. I've never taken any notice before.

[REDA9X]

So I gather no one can tell me for sure? I ran Holden they tried to tell me it was just a normal LSD. Unfortunately most of thier staff were still in nappies 15 years ago when these were new! HSV most of the engineers are retired.

[76lxhatch]

Not for sure, but I would guess being a viscous setup it would have to spin one wheel before it engages the other much like a torque converter; most people's complaints with them is that you don't get torque transfer as quickly as a normal limited slip which would back that up...?

[TerrA LX]

Isn't viscous just a marketing gimmick much like magnatec oil, all LSD's operate in a viscous fluid lol.

[76lxhatch]

I guess the actuation/trigger is viscous (or at least hydraulic) but the coupling action itself in a cone or clutch LSD transfers torque via direct drive of the friction of two surfaces (cone against housing or clutch lining against plate). A viscous diff transfers the drive itself via the fluid, in (I'm assuming, may depend on specific application) a similar manner to a torque converter where there is no direct drive. This was a big thing when it first became commonplace in applications like centre diffs on AWD cars, controlling the coupler allowed the drive to be tightened or loosened by electronic control, varying the front/rear drive percentages.

[ls2lxhatch]

The BTR Hydratrak is basically a hydraulic version of the Detroit Truetrac.

 

The Detroit Truetrac uses worm gears to transfer torque to the wheel with the most grip. The Hydratrak uses a sealed hydraulic coupler to transfer torque to the wheel with the most grip.

 

This is an article from Perth Street Car Vol 4. No 4 (1997).

 

Hydratrack.pdf

 

I remember hearing stories of the Hydratrak overheating if you gave it a hard time.

Edited by ls2lxhatch, 22 July 2013 - 10:25 PM.

[rodomo]

Hydra tractor?

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[TerrA LX]

Hydra tractor?

 

 

I just want one...

[REDA9X]

Thanks for the replies. I'm not sure if my diff is working as advertised though. The answer i got back was, "go do a burnout and see if it's working or not'.

[TerrA LX]

If one wheel turns and not the other then one would assume the LSD is not functioning.

[76lxhatch]

My thoughts were to the contrary that it could well be operating fine, I believe you'll need to get one wheel spinning at a bit of speed before it will engage the other