Awd binding again

[Trevor]

Originally Posted by oab_au

As the binding goes away when you put the fuse in, the C solenoid and the transfer valve is working OK. The binding could be caused by excessive line pressure. The TCU applies pressure to the transfer clutch duty cycle, in accordance with the line pressure at the time.

When cruising there should be enough transfer pressure applied to give 10% drive to the rear, if the line pressure is higher than it should be, the clutch pressure will be higher than the 10%, to cause the binding.

The best way to sort it out would be to check the transfer pressure at the rear of the box, to see if it is higher than it should be, if so check the line pressure. Do you have the shift kit fitted? as this can cause the problem.

Harvey.

Agreed Harvey, and I wonder if he has the resistor out of circuit, or if the circuit is faulty ? I hope there is a following report which may assist others.

[redsvx94]

Thanks for the considerations.
Hi Trever, yes Front wheel drive area is worth considering but the vibration is a definite "rumble on my butt" feeling coming from behind, which disappears when I input the FWD fuse. Hi, Harvey a very good point with tranny resistor. I think I vaguely remember seeing a post stating, removing a resistor resulted in a binding. As far as I can see the resistor is there, I have never touched it. But that doesn't mean the resistor is not bad and electrically disconnecting. I will check the resistance and report.
I recently was wondering about the resistor since I’ve been starting to be able to feel the shift from 3rd to 4th more clearly, which has been almost impossible to feel in the past. May be it's just the tranny getting old.

[TomsSVX]

A bad resistor has been known to cause binding issues, check the resistance on it and check back, I cannot remember exactly what it is at this time

Tom

[redsvx94]

The resistance is 12.3 ohm. I think this is close to the spec? It seems resistance is there, and the connector looks pretty clean free of rust.
SO, the SEARCH continues. Is it possible a too low line pressure could cause biding? The only potential issue with shifting of tranny i can think of is that it seems kicking a little when decelerating, at low speeds.
By the way, just to reiterate, An interesting thing to me was that the bidning seems to be going away under neutral. Does this tell anytning?

[TomsSVX]

High pressure will cause binding not low. Unfortunately your resistor is close to spec which means it probobly is still good. So... maybe Trevor is right in saying maybe it is somewhere else in the drvietrain

Tom

[redsvx94]

O.K. What part of drivetrain would cause a binding
but not when there is FWD fuse in? I vaugely remember a post about binding problem caused by some u-joint in the rear, which went away when the FWD fuse is in.
Here it is. What do you guys think? How would l go about checking such joint?

Originally Posted by jpsull

I just went through this same type deal. Replaced the tranns, replaced the TCU, had the tranny replaced under warranty. It was a bad u-joint in the rear drive line in the end. Hard to see so it's hard to inspect. Putting the fuse in puts 12v to the transfer clutch so it makes you think that the transfer clutch is bad because the sypmton goes away when there is actually just a bad end on the drive line. Relatively cheap fix compared to everything else I paid for.

[TomsSVX]

he is talking about the driveshaft that connects the rear differential to the transmission. This is probobly where your issue is happening

Tom

[redsvx94]

O.K. It seems SVX has left and right joint, each about $200. I don't feel any difference between turning left and right, so I should assume that both are bad? Is there any way to check whether the joints are indeed the culprits? Or something I can tell to i.e. Midas to check it? I assume tranny don't need to be touched to check or fix them?

[TomsSVX]

not axles.... driveshaft. It runs down the center of the car from the back of the tranny to the front of the rear differential. This is probobly where your troubles lie

Tom

[SubyLuver]

I am having some problems with my 92' svx shifting erratically while driving at a steady pace and also tranny binding... I checked the TPS, with the car ON but not started I get a .48 volt reading (which should be accurate enough I think). Any other ideas?

[redsvx94]

Ah, Sorry. Then is it the one with part number 33123 shown in the attached schematics? How would one go about checking it? When I've taken mine into a transmission shop, they lifted the car and checked AWD by hitting the gas. Every time he hit the gas, the rear wheel would rotate, so he said AWD is working, but he couldn't find the source of binding. Would listening to that driveshaft using stethoscope, while the rear wheel is rotating, verify whether this is the culprit?

Also does any one know whether the transmission or transfer case should be dropped to replace this part?

Originally Posted by TomsSVX

not axles.... driveshaft. It runs down the center of the car from the back of the tranny to the front of the rear differential. This is probobly where your troubles lie

Tom

[TomsSVX]

Loook under Subaruparts for the propeller shaft, this is another term used to identify the driveshaft

Tom

[redsvx94]

Thanks a lot Tom! The joint itself seems to cost only about ~160$, it is cheap enough to just try and replace it, if I could do it myself. Is there any how-to or could any one give me some description of procedure? I have most of standard hand tools and replaced timing belt, seals etc without too much problem, but that was thanks to some good write-up as well as some additional helps from this site. Acording to a quick look at available posts, it seem alignment is a critical issue...

[TomsSVX]

No it is not that simple. What you need is the entire assembly which will cost the $488. The U-joints that are not rebuildable are probobly what is causing your problem. So that means you need a new one or a good used one

Tom

[nipper]

If you can find a driveshaft shop, they will rebuild them for you. I know on the legacy they use a ford ranger universal joint, not sure if the scx is the same. It cost me 120.00 to have this done. Also they will install a servicable joint.

nipper