Tracking the torque bind demon

[captainehh]

My knowledge of my 97 OBW has increased tenfold from everyones' collective info on this board!

As the subject implies, i've got torque bind issues. The car has 68K. The tranny was rebuillt about 10K ago by the second owner. I recently bought the car for a steal ($3,500), knowing that repairs needed done. The car was in an accident and sat for three years (crunched from the front and rear). It was repaired and from there it ended up in the 2nd owners hands, and not too much later into mine. It's a great car and I'm excited to kill the demons that haunt it.

 

I've ruled out tire circumfrence discrepancy-The tires are all within a 1 inch range. I rotated them too

 

Wheel bearings are good

 

CV axles are new

 

Replaced front and rear diff fluid with 80w 90 synthetic

 

I swapped the trans fluid and filter and replaced with synthetic fluid......

 

Here's where my question is and hopefully an answer-

 

Took it down to a reputable tranny shop to give them the history and ask some questions. They see a ton of subes (lots here in OR) and said that they've never seen a sube with torque bind that changing the tranny fluid didn't fix. He recommended pulling the drain plug and letting 4 quarts run out. After this, replace the lost 4 quarts with Chrysler brand ATF+4 which apparently has a special friction modifying component. Is this compatible with the rest of the synthetic fluid thats in the 4EAT? Anybody heard of this trick working?

 

And also, digging thru the archives, I've stumbled across mixed info on running around with the FWD fuse installed. I'd love to hear more opinions. I have no choice but to drive the car while i'm tracking down the problems. Am i doing harm be keeping it in FWD, which eliminates the torque bind shudder?

 

Thanks

[LegacyT]

fluid has a minimal influence on torque bind. Torque bind is caused from worn clutch packs, you probobly need new ones. That tranny shop sounds like they have no clue what their talking about.

 

Mark,

[patcal]

Mine was cause by a bad TCU. I also had a bad duty solenoi c but the computer took awhile to track down. Lots of help from this forum. Do you have any tranny code showing up?

[captainehh]

It'd be great if this is legible. This is the receipt i aquired that outlines the 4EAT rebuild. I had to scan the receipt and turn it into text format so i could attach it under the minimum file size. Sorry for its scattered nature-it's the best i could get it.

 

Patcal-

No, there aren't any flashes from the tranny light on the dash. Everything is normal.

[captainehh]

Here's the attachment

tranny text.txt

[captainehh]

Just wanted to throw this thread out there again. I'm a bit surprised I didn't get more feedback.

 

Anybody have any final comments on driving for extended periods of time with the FWD fuse installed? Alias- you seemed to think that you shouldn't drive more than 30 mph with the fuse in. Whats the logic behind this?

[alias20035]

Originally posted by captainehh

Just wanted to throw this thread out there again. I'm a bit surprised I didn't get more feedback.

 

Anybody have any final comments on driving for extended periods of time with the FWD fuse installed? Alias- you seemed to think that you shouldn't drive more than 30 mph with the fuse in. Whats the logic behind this?

 

The warning in the owners manual (it was in my 93 Legacy's owner's manual, I'll check my 2001 Outback manual, but the 4EAT's are not any different now than then).

 

There was both a speed and distance limit, something like 30MPH for a max of 30 miles or something like that. Maybe it was 50MPH, I have only owned 5MT Subaru's, so I don't have the fuse.

 

But it is definitely not a good idea to use the FWD fuse to delay a repair to the AWD system, it is intended for short term emergency use only, such as when using the spare tire. The FWD fuse holds the transmission in a full front wheel drive mode, which never occurs otherwise (there should always be a minimum of 10% rear power).

[remarcable]

I heard awhile back on this board and others that a Rental place was running subarus in FWD during the summers to cut down on gas costs. No ill effects were reported on the cars. I can't confirm those reports, so it could be fiction.

 

I think the owner's manual warns about impending doom regarding using the donut spare. I'm not sure it said anything about using the FWD fuse with 4 perfect tires.

 

I also seem to remember a guy named Kevin who had a beefed up impreza sport which he drag raced and used FWD mode on the dyno to calculate horsepower.

 

I'm not sure if that would even work since the rear axle is still attached to the front, just not receiving power.... correct? It is still dragging even when in FWD mode.

 

In regards to draining the 4 quarts in the ATF pan, that doesn't do a whole lot if you are having serious fluid problems. The best thing to do is a flush which gets the 8 quarts left in the torque convertor.

 

You should always do a flush when switching to synthetic or back to regular for best results. I personally would avoid mixing synth ATF and regular ATF.

[blitz]

Alias20035, I believe that those limits that you describe are for towing. With engine not running, the trans pump isn't supplying any lube to the rotating mechanisms and hence the speed/distance limit to avoid tranny damage. I'm pretty sure the car could be driven indefinitely with the fuse in (FWD mode).

[intrigueing]

How bad was the damage from the accident? The car may not be 100% straight, causing the car to think wheels are slipping, when it is just the car out of wack.

[4FOR4]

I'm sure what you mean by torque lock but I recently had a problem where on turns the back end jumped around like being in 4 wheel drive on dry roads. Sort of like the tires where sliding due to difference in turning circles front to back.

 

The solution was to replace the torque conveter in the rear differential. After time and mile these things develop small grooves in the spline and the rings get caught in them and can't slide.

 

I don't know if that's your trouble, I didn't see a sysmptoms

[Phillip]

1" difference is a bunch! Measure the distance around each of the four tires with a piece of string; I'd be concerned about more than 1/4" variance.

[captainehh]

Thanks for the replies guys-

 

I've got a bit of an update on the situation. I'm a poor/extremely busy grad student that hasn't been able to get the time or money to address the torque bind issue until now.

 

I drove my sube down from OR to the bay area just recently. I gambled and drove it in FWD most of the way. I did a little test and put it in AWD for a portion of the trip. The seat-of-your pants shudder is still there when making sharp turns at slow speeds. Also, after about fifty miles of 70mph driving, when I let off the gas to coast, a grrrphhwerrrrrggghhhh noise came from the tranny trunnel. This noise occurred only after driving for a while and only above 45 mph when coasting. Worrysome. The noise left when i reinstalled the FWD fuse.

 

I'm not sure of accident's extent. The allignment couldn't be more perfect though.

 

I'll re-check the tire circumfrence now that i'm in a place with better tools.

 

Swapping out 4 quarts of syn ATF fluid for Mopar ATF + 4 helped somewhat. I was sorta thinking that too. The fact that i should get all the fluid flushed and replaced instead of just adding 4 quarts of the new stuff.

 

Does this noise happening in a coast- -at-high speed situation give any more insight into the prob? I love the car and really hope to nail the bugs so i can sleep at night.

 

Thanks and merry christmas!

[intrigueing]

How does your front diff fluid look, from the sounds you are getting, it does not seem that there could be a "simple cheap solution" Keep the fuse in - AWD engaging at 45 mph with dry pavement = quick damage.

Maybe your subaru will be fine with the fuse, and you can just be happy with "the beauty of front wheel drive".

[captainehh]

yep, swapped out the front diff fluid and it looked fine. All this is very intrigueing because the tranny was overhauled 15k ago and the normal culprits in the 4EAT were replaced.

[intrigueing]

Tires seem like a possibility, try inflating to 35 psi and rotating them, if there is significant wear differences front to back, replace them.

[captainehh]

Thanks for the thought- I've done that actually. I recently re-measured with better equipment and they're all actually within a 1/4" of eachother. The saga continues.....

[meep]

1. The chrysler ATF+4 is a synthetic version of ATF+3. Same friction properties, just synthetic. It's a good oil and has a 75,000 mile life, 50,000 under "severe" conditions. May have a smoother (lower friction) property than dexron-- which causes premature engagement in chrysler ATs (we have a minivan and are well-studied on this...). It's a good oil, but I'd listen to make sure nothing is slipping on harder shifts.

 

2. Driving with that fuse in won't hurt a darn thing. "10%" is really misleading... since under "2wd" conditions it's not a solid connection, but a friction-based connection. If the car is accelerating in a straight line with no slip, the front end does the pulling and the end is under a zero-strain condition. If you'r turning or have very mild slippage, it adds it's motive force up to the point where the clutch kicks it a bit. Besides, that trans looks ALOT like, like, nearly identical to the 4wd with manual 4x4 engagement that shipped on earlier soobees, which could certainly handle 100% to the front end. Or, if you don't want to believe me, always drive with less than 90% throttle... Stick it in and save your money until your ready for a pack rebuild, tailshaft replacement and possible solenoid R/R.

 

3. Enjoy the car!!

 

Mikey:D