I have the 1998 Subaru Legacy Lancaster, a Japanese import model, very similar to the Outback. It is supposed to be AWD (automatic gearbox) but there is no drive to the rear wheels. The driveshaft turns the rear diff / wheels when jacked up, there's no drive out of the transfer case. There are no warning lights on the dash, no error codes either, and the FWD fuse isn't in. I have cleaned all the terminals and plugs related to the transmission. I have replaced the speed sensor #1 on the transfer case. There is often a sudden thump on hard acceleration as if the rear drive briefly engages. There are no grinding / scraping noises as would be expected from broken components in the transfer case. The best I can deduce so far is that the anti-bind solenoid is operating full time, disabling the drive to the rear wheels.
You will likely need to replace the following:
Duty C Solenoid
Transfer Clutch Pack
Reduction gear
All of these parts are located in the tail end of the 4EAT automatic transmissions. The reduction gear can separate from its hub and damage the above mentioned parts too.
SOURCE: Why is there no drive to the rear wheels of my Subaru Legacy AWD?
Hi there now you say that occasionally the behaviour changes and it feels like you have all 4 wheels driving. Now is there any chance that the previous owner has modified the sensor or bridged it out to stopthe 4 wheels from driving.
Now firstly you need to establish if it will engage all four wheels to drive by simply jacking up one side of the car and putting it into drive and watch to see if the elevated wheels drive while in gear.
The whole idea of the anti bind solenoid is to allow the rear driving wheels to revert back to a conventional differential to allow you to corner efficiently.
Now in my opinion I would find the terminals for the duty c solenoid and disconnect them and simply get a battery or run a power source from the main battery and simply give the solonoid a feed
direct from your power supply and listen for it engaging and disengaging to see if yhe solenoid bis actually operational. It could simply be stuck in the on position like a starter motor sticks and the bang you're hearing when u accelerate hard may simply be the solenoid being forced back to its natural position of being off
The high acceleration from the vehicles engine would also cause a surge of electrical power and may be causing the solenoid to revert back as it may just be stuck on.
1. Check the solenoid for operation using an external or direct power source listen for it clicking on n off
2. The solenoid bind sensor may be faulty or bridged out to only allow fwd. So find it and check out the wiring for breaks and bridge wiring which would keep the solenoid engaged
3. Check all the fuses and relays especially as solenoids tend to use relays rather than a fuse
In my opinion this may just be a simple case of a stuck solenoid keeping your 4 wd on a 2wd basis.
Find the sensor and check the wiring and if possible remove the rear differential solenoid and check for operation.
Try this above and get back to me as it could be linked to your liaf sensing valve and the throttle potentiometer. But lets start of with simple elimination of the solenoid and its sensor
hope this helps
thanks davy
.
Testimonial: "Thanks Davy! There is a multi-pin plug on the side of the transmission close to the engine, would you happen to know which of these terminals would go to the Duty C solenoid? I've seen 3 sensors at the top of the transmission, a thick cable going to each, the one above the transfer case when removed (1 M6 bolt) is a magnetic cylinder about 25mm long and 15mm in diameter. Would you know what this would be? Thanks again."
SOURCE: Why is there no drive to the rear wheels of my Subaru Legacy AWD?
It may be a problem with the transfer clutch. Please get the mechanical side checked too. Mostly the problems are small but we search for it in the most complicated places.
Testimonial: "Hi people, I think I've finally solved it, thanks for all the suggestions. I drained the transmission fluid and removed the transfer case. I found that with no oil pressure the rear output shaft was connecting to the front axles - yay! So I figured that NO oil pressure to the release piston was needed for 4WD. It seems to me that the solenoid being closed pressurises a piston which slides across and lets the high pressure oil escape which would otherwise have been releasing the drive to the rear wheels. This leaves the rear drive engaged until the solenoid gets the open signal. I removed the duty C solenoid and valve body and gave them a good clean with compressed air. The solenoid is normally closed, and opens with the high frequency 12v that is sent to it. However, in the closed position there was a small leak while blowing into it. I replaced just the solenoid (from my friend's Subaru graveyard) and it was such a thrill to get the rear wheels spinning in the paddock. The drive still engages with a clunk, not steady and smooth transition, but better than nothing. The next step is to put a switch in the wire that feeds the solenoid to enable pure 4WD when I need it."
195 views
Usually answered in minutes!
×