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4wd loyale rear diff

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So I've been told that I should not drive my loyale with 4wd engaged on dry pavement... I assume it is some sort of LSD set up? What diff can I get that's the 3.90 that I can run it in 4wd I'd like to run it in auto cross dirt/pavement course that I've found

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It's because of the trans, not the rear diff. You either have front or 4WD with no center diff so it might bind a little around corners on dry pavement.

Edited by Crazyeights

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So I'd have to do a tranny swap and loss the 4wd option? It would be awd what tranny would I need to look for?

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Using the 4wd on a dry, hard surface can damage driveshafts, the propshaft, the rear differential and the transfer gears. The reason is that there is no central differential at all so any slight difference in front-to-rear rotation caused by, for instance, slight differences in tyre diameter (rears will nearly always wear less than fronts) will cause 'transmision wind-up' in which all components (mechanically) aft of the gearbox in the drive-line are under unusual load. I've never had to use my 4WD in dry, hard surface conditions and so I don't know why you'd want to do it. But if you're after the performance of a tarmac 4WD car, you'll need one with a centre differential.    

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What you need is a full-time all-wheel drive transmission. They came in later 80's models of the RX, some XT's (1987.5+), and I think rarely GL-10's.

Some are also available in dual range, and with a locking center differential.

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I have a custom RX (3.9 ratio XT6 gear set) FT D/R box with locking center diff and a clutch style rear LSD in my '83 wagon. It's a nice combo for old school parts. You would probably do well with an EJ trans also, but that opens up a whole new can of worms.

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if you turn a tight corner with the 4wd engaged you will immediately notice the problem.  the front and rear axles are built to allow the tires on each side to rotate at different speeds for corners and because no 2 tires are identical.  they are not built to allow it front to back (in general on 4wd's like most of us have) so you can only use it on surfaces where your tires can slip a bit (you wont notice it when they do, but the car will). even hard packed dirt isnt the same as concrete or asphalt.

 

AWD is designed for use when all the tires have good traction, so you want to search that out and find out what parts you need.

 

most of the 4wd cars had 3.90 gears so you likely have that now.  no idea what the AWD trans you find will have.  its more common to want to swap to the 4.11 gears from other models to lower the gear ratio.

 

I would think if you want an AWD track car, it would be best to start with an AWD legacy/RS/impreza.  but if your dead set on using the loyal, then find a car with the center diff like mentioned earlier or find an early 90's rolled over subaru with an EJ motor and swap the stuff out.  its not quite that easy, but it has been done before

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simple answer to your question is an xt6 trans, it's already a 3.90 ratio and you can wire up the center diff lock and it will function like your push button 4wd does now when you need it to

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simple answer to your question is an xt6 trans, it's already a 3.90 ratio and you can wire up the center diff lock and it will function like your push button 4wd does now when you need it to

Agree, all you need is EA82 Turbo 25 spline front axles and it should bolt right in.

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Well the tranny is on hold until I figure out the "knocking" coming from the ea82... Sounds like a rod knock but not sure I have new nkg iridium plugs (checked to make sire they were still tight last night) New belt only about 200 miles on it. Doing an oil change on it when I get off work. Out of ideas beyond that.

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TOD can be very loud sometimes - if you search Tick of Death on this site you'll find loads of info - but if it's a knock you'll need to inspect the botom end.

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Check your cam tensioner pulley mounting bolts.  I've seen several that have come loose and sound like a knock in the bottom end.  Hopefully it's something as simple as this...

 

Gearboxes - the EJ AWD would be the easiest to find.  You can fit one of these in an L series gearbox casing without any troubles - just need a single range EA gearbox to use the front casings on the EJ box.  The speedo drive gear on the EJ gearset is different to the L series one, so your speedo might be out unless you can work out what follower gear is needed.  Then you'll need to mod the gearbox crossmember, shifter linkages and prop/tail shaft.  By putting the EJ internals into an EA set of casings you end up with a bolt on AWD gearbox to an EA82 with the stock clutch setup...

Clear as mud?


Cheers

Bennie

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