As the title says, 96 OBW Auto, came with torque bind. I took off the extension housing, cleand stuff up, put it back on, and instead of binding, it started going bangbang on turns. OK, perhaps it is the TCU not handling the duty C correctly, changed that out. No change. swapped out the tranny with a 97 Outback auto tranny.

 

Still no change.

 

You read that last right. swapping in a new(er) tranny did not fix it. If I put the FWD fuse in the sound goes away, so I know that the problem is in the rear drive part of the driveline. I cannot imagine that two trannys would have exactly the same kind of failure. I suspect that the rear diff is lashing loudly, or even slipping, and the previous torque bind actlually masked this problem. I have a rear diff from a 2000 Outback wagon that I can swap in, if the ratios are the same. Does anyone know if a 2K rear diff is the same ratio as a 96? can anyone think of anything else that might be the problem?

since you didnt have the bang bang in the beginning,i dont think its the rear end. with the fuse in the rear end is only [following]where the car goes,no pressure.i think it is the clutch pack engauging violently.if you turn the rear end over by hand[jacked up] you should feel or hear a rough ratchet sound if the diff is bad.

have an extra TCU to swap in?

 

your tires all match good? driveshaft doesn't have a bad ujoint? rear diff issues?

 

i have that pictured we talked about awhile ago scanned into my computer, brought a disk to work today to email it to you and the disk is bad...grrrr.......

Are you sure you have the same front and rear final drive ratio???

Are you sure you have the same front and rear final drive ratio???

 

the tranny is only a year different (97 OBW tranny in a 96 OBW) I'm fairly certain that they are the same. I moved the driveshaft by hand with the rear wheels on ramps. the rear diff was going tink tink when it lashed. the noise is only when turning (well it takes a couple of seconds to die down when you straighten out). OK, the AWD clutchpack is engaging harshly. That would make the sound but is that not what normally happens? If not, how is the drive ratio altered by the duty cycle to the Duty C solenoid? And two trannies bad in the same way, in a row? that is way beyond coincidence. . .

 

does anyone know if the 2000 OBW rear diff is the same drive ratio as the 96 (or 97 for that matter) ?

Gnuman, the reason i think it is the clutch pack is,when i first bought my 91 and got hungup the first time it did the same thing,sounded like[and felt like] i was dropping it in gear at 5000 rpms.i was told by a local mech. to run a can of trans x for about 150 miles and drain,i did and the condition cleared up. what really causes this i dont have a clue.

Here's a weird idea. Leave the AWD engaged(don't put the fuse in). What if, as an experiment, you took off the rear drive axles? It would leave the rear diff in place but I'd guess there could be NO torque binding. I dunno. doesn't sound practical seeing it written down! hah!

heres one other thing that comes to mind,in that rear cover there is two o rings if these get pinched or out of whack pressure will not be consistant.just a thought.

OK, the problem I have with it being in the transmission itself is that the odds against two different transmissions in a row having the exact same failure and symptoms is infantismal at best. If I hit odds like that I should be playing the lottery. . .

 

That said, I suspect that the problem is in the rear diff, but the TCU may also be part of the problem. I have a spare diff from a 2K OBW, but I don't know for sure that it is the same ratio as the 97 or the 96. . . If anyone knows that, it would be of great assistance in this. Also, am I wrong about the method for modulating the power split in the AWD system? Is it some other method than the duty cycle of the solenoid?

when you first take off in first gear the awd is working at full go,when you pick up speed it starts reducing,if you put the fuse in this will stop the bang bang unless the clutch packs are sticking.

when you first take off in first gear the awd is working at full go,when you pick up speed it starts reducing,if you put the fuse in this will stop the bang bang unless the clutch packs are sticking.

 

The bang bang only happens when turning, now when going straight (I thought I had mentioned that. . .) and happens at all speeds. Could this be something other than the diff then? This started only after I cleaned the Duty C in the first tranny, and I was thinking that the torque bind was keeping it from happening. My guess was that the bind was keeping a constant pressure on the diff, and with the AWD working right, the diff was only getting intermitant pressure, causing gear lash, which would result in the sound. this lash would only be happening during turns as that is when the AWD system is adjusting the drive split from front to rear. . .

 

In other news, I feel what seems to me to be a lot of free play in the rear diff, which may be contributing to the problem (more room to swing, making more noise). .

Some one mentioned tires.

 

I replace a torn tire with a new one and that small difference in size caused a similar type of banging.

 

Just a thought.

Hentai

if you could take the drive shaft out of the car ill take bets it will quit, i still think its the clutch pak or seloniod,a bad rear end dont do these kind of things.

going around a corner has nothing to do with the front to rear split,unless the clutch packs arent releasing to allow slip for the difference in wheel speed.

SOLVED!

 

Turns out that the driveshaft center berring was in wrong, and the driveshaft was not lined up correctly. this placed stress on the center berring and the U-joints, causing them to bind. All is well with this car now.

Hey, Gnuman! What do you mean the center driveshaft bearing was "in wrong?" How do you do that?? Just curious....