[Author Prev][Author Next][Thread Prev][Thread Next][Author Index][Thread Index]

Re: Questions on AWD, ABS, and locking the rear differential

LToy@aol.com sez:
> Not counting race/competition cars, were ANY quattros equipped with LSD?  

The '90?-on V8 Q had a Torsen rear diff.  (And soon, very soon, my '91
Coupe will have a Torsen rear diff!  Finally!)

> This vacuum hub lock is a new one to me.  The 4x4s I've seen/driven with
> self-locking hubs usually unlock after disengaging 4wd then driving in
> reverse for about 50 feet or so. 

Yes, there are two forms of auto-locking front hubs: vacuum lock on one hub,
and second, the true auto-lock.  Both suck big-time (perhaps vacuum sucks a
bit more!)  There are two problems: 1) these mechanisms need to carry lots
or torque (that's the whole point, now isn't it?), yet they can not be sized
any larger than the comparably simpler manual hub locks, and 2) the mechanisms
are complicated little buggers (in the case of auto-lock, with pawls and things;
in the case of vacuum, vacuum lines and an external vacuum motor) and are thus
always failing when you need them most.  So the auto-lock mechanisms are fine
for the nice driving that most current SUV owners subject them to, but do anything
half-serious, and you will be wanting manual hub locks.  And, let me say from
experience, retrofitting manual locking front ends onto current vehicles is a
rear nasty project!  (But well worth it!)

fhd@interport.net | The computer in as inanimate object; therefore it
  1 212 559 5534  | must, eventually, respond to reason.
  1 917 992 2248  | 		-- Anonymous
  1 718 746 7061  |