1985 GL 4WD problem

[Unit562]

o/

I tried a bit of searching before hand and didn't come up with anything similar to my problem, and NASIOC didn't have much help other that the direction to this site. (Which I'm ecstatic about.)

I bought a 1985 GL from my in-laws, I found the car a year ago and was
about to buy it when they said they needed it more, so I let them snatch
it up with the intent of buying it from them later on. Well, that time
has come and now it's mine. They drove it maybe 2,000 miles in the year
they owned it and did improper maintenance. Now it's got a dead lifter
and 2 blown head gaskets.

I'm not very concerned about those two issues, they're easy fix's for
me. I am however concerned with my 4WD system. FWD works perfectly,
it'll even do a one tire fire if I'm not easy on the peddle. 4hi it makes a ton of gearbox noise from the center diff, and it feels like one of the rear wheels
locks up and just drags, all while going straight, I haven't dared to turn. 4lo makes the same noise however it seems to
work just fine. I haven't really tried 4lo that much due to the fear of
it breaking on dry pavement. The weirdest part of all this, is it only
goes back in 2wd if I'm going in reverse. It refuses to go back while
moving forward. If you've got idea's before I start cracking the box's
open, I'm all ears.

[DaveT]

Check that all 4 tires are the same brand, size, etc.

[Unit562]

Check that all 4 tires are the same brand, size, etc.

 

I'd like for it to be that simple, unfortunately it's not. 

[DaveT]

Any chance someone swapped a transmission or differential and miss matched the final drive ratios?

[TomRhere]

You mentioned "dry pavement".

 

That's a No-No with this era of Subaru's. Loose stuff only. Sand, snow, mud, dirt, gravel.

There is no center diff in the D/R trans of the U.S. models. So that locks the front and rear together creating binding.

Evident by only coming out of 4WD by backing up.

 

But, the possibility of mis-matched front/rear diffs as DaveT said is possible.

 

Couple of easy checks;

 

1st, jack rear of car up enough that both rear tires are off the ground.

Spin one tire, note which way opposite side tire spins.

Both spin the same direction, you have an LSD rear diff, and someone may not have changed the ring gear to suit front diff ratio.

They spin oppositely, you have an open diff, the standard on most of ours.

 

Now lower the rear and jack one side up to get front/rear tires on one side off the ground. Put it in 4WD mode.

Note position of valve stem on one of the tires, spin the other tire one complete revolution. Check where the valve stem is one the tire you did not spin, it should be in the same spot as it was. Meaning gear ratio's are the same front/rear.

Edited November 18, 2016 by TomRhere

[Unit562]

You mentioned "dry pavement".

 

That's a No-No with this era of Subaru's. Loose stuff only. Sand, snow, mud, dirt, gravel.

There is no center diff in the D/R trans of the U.S. models. So that locks the front and rear together creating binding.

Evident by only coming out of 4WD by backing up.

Pretty much why I've stopped trying. I'm waiting for snow fall to really give it a good test, or rain and some mud. I have engine work to do in a few hours, figure if it's going to be down for a few days I may as well crack other stuff open if need be. I'll probably wait. Now to figure out this noise that sounds like a lifter, off to a new post!

[heymulderitsme]

Hey!

 

I seem to be having a very similar problem, but I guess I was asking for it.

 

Lots of seizing/trouble turning anything resembling sharply/lurching while getting up to speed in 1st gear.

 

Not sure it's getting all the way out of 4WD at any point despite shifting out of it.

 

It's an '88 GL Turbo body with an '85 transmission with 4hi/4lo and a '93 EJ22 Legacy L motor up front. Probably too many variables to pin down, but I'd appreciate some wisdom if anyone else has any ideas!

[scoobiedubie]

Add fluid to the transmission and differential.  I thought that the LSD only came on the 3.2 ratio gl10 turbo models.  The standard gl is a 3.8 ratio, as I recall.  They cannot be mixed.

[heymulderitsme]

I think I read another thread from a few years ago where someone had the same issue I'm having.

 

4x4 lever all the way up = 4 Lo

4x4 lever in the middle= neautral/car will not move in gear otherwise but will coast like a car that is actually totally in neutral

4x4 lever all the way down = 4 Hi

 

I've been able to drive it somewhat successfully in 4Hi on pavement, but it seems like the differentials are locked in a weird way or that I just do not at all understand how this 4WD system is supposed to function.

 

At any rate, shouldn't there be a position on the lever that allows the car to be fully in FWD? If so, should that be with the lever all the way down? Or in the middle of the other two settings? If it is the middle setting, why would the car not move when in gear? Is this as simple as adjusting the rod of the 4x4 lever where it enters the transmission?

[DagdaS]

Not sure what trans you're running, may be similar to the one I have (though mine is out of an '86). I have the D/R, and it is a 4 position lever. Bottomed out (no downward play in handle) is FWD only. Up once is 4Hi. Up again is True Neutral/Towing. Up one last time (3rd time for those not counting) is 4Lo. From time to time she gets twitchy, whether out on one of the "Primitive Roads" we have out here, or my 1/4 mile long curvy, hilly driveway she decides she doesn't want to come out of 4WD, no matter which range. When that happens, I put in the clutch, put her in reverse, let out the clutch until she's just starting to move, then back to Neutral. She'll let herself be put back in FWD then.