Lost AWD on Saab 9-7x

[Rouxzy]

Hey everyone been a while since I've been around, been real busy with family and the saab 9-7x has been good. Until recently. I lost my AWD. Put it up on the lift and what I found is that the front drive shaft is engaged to the transfer case at all times. Both front wheels spin freely of each other. I started truck up while in the air and put it in drive. Rear wheels spin along with the front drive shaft but front wheels do nothing. I haven't heard any crunching or clunking noises at all. Is is possible that my front differential is toast? Could this be why my wheels are spinning freely? Plus I question why the front drive shaft is always locked in. Is my encoder motor toast also?
Tom

 

[carshinebob]

Intermediate shaft teeth are known to wear smooth. Disassemble and inspect. I just changed the shaft and disconnect on one of mine. ~BOB

 

[Rouxzy]

Thanks Bob. I do have over 200k on it so that makes since. I'll give it a look after the holidays, on my way to Chicago and Iowa to visit family for the holidays and report back on that. But any idea why the front drive shaft is always engaged?
Tom

 

[Mooseman]

Just the way the system works. The equivalent on the 4x4 trucks is the auto position. Front wheels remain locked so that they are ready to take the torque when the transfer case is engaged. I call it the "slip/bang" system. Rear wheels slip and it quickly engages the fronts.

 

[Rouxzy]

Yes, I understand that Mooseman, but why would the front drive shaft that is governed by the encoder motor be spinning when it should be off?

 

[mrrsm]

As suggested by @carshinebob ...This explanation from another victim makes sense as the reason for this failure and the odd "spinning shafts" ...and how he had the problem repaired, with an excerpt from:

https://repairpal.com/awd-not-working-113

“I had my drive line guy repair it. The front and rear drive shafts were spinning the same speed so that is why the PCM thought everything was ok. The intermediate shaft and coupler were stripped out (splined connection). Replaced both parts and reassembled.”

 

[Mooseman]

Yes, I understand that Mooseman, but why would the front drive shaft that is governed by the encoder motor be spinning when it should be off?

With all four wheels on the ground and turning, it is because of the always locked front diff. Now, if it is spinning with all 4 wheels off the ground, then the transfer case is always engaged. If you remove the encoder motor and now the front shaft doesn't spin, then I would suspect the encoder motor being dead. I had that and the front wheels would crow hop on dry asphalt, just like a 4x4 truck engaged in 4hi.

 

[Rouxzy]

Had time to dig into it today and found the encoder motor locked in the engaged position. Replaced it and fixed that. Took the intermediate shaft bearing assembly out and found the intermediate shaft and the sleeve smooth as a babies behind. Rather than buying the entire assembly it looks to be alot cheaper to just change out the sleeve, seals, and bearings for less than 150.00 compared to close to 400.00.

Two questions: What is the trick to remove the intermediate shaft? Recommendations on where to purchase the parts?

Thanks
Tom

 

[carshinebob]

the intermediate shaft should pull strait out. It's not fastened in with any thing. I sourced my intermediate shaft from ebay, $20 + ship, used. I would recommend getting one from a 4wd not an AWD just because there's less wear on parts that are disconnected most of the time. The disconnect was from ebay also and I paid about $200 for that, new. ~BOB

 

[m.mcmillen]

These front axle disconnects are good. https://m.ebay.com/itm/Bravada-Trai...WD-Axle-Disconnect-15200680-NEW-/121514103346

 

[Rouxzy]

Thanks to all for the advice. I replaced the shaft and the intermediate shaft bearing assembly and everything is back like new. Again, thanks for all the help. Bob, like you said the shaft just pulled right out. Thanks
Tom