I still don't believe it!

I have a 1997 Legacy L Subaru SW with 125,000. Car runs smoothly with get-up-and-go EVEN with the AC engaged. Sharp turns create a shuttering / intermittent lurching. I'm told by a trusted mechanic and transmission "experts" that the transmission needs replacing. The transmission fluid and screened has been serviced. How can a transmission affect turning? Comments please. Thank you.

Reply to
Passenger
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At the very rear of the transmission is a clutch pack that provides the AWD. It is designed to "slip" when the car is in a turn because the wheels on the side of the turn have to turn less than the outside wheels. Running mismatched tires is the classical way to damage this clutch pack. Good news is if indeed the clutch pack is damaged just it and not the entire transaxle can be replaced. Cost savings is significant. Transmission doesn't even have to be removed. Under the hood, thinking on the passenger side, there is a small black box with the letters FWD. Inside the box there is a fuse. Insert the fuse in the holder and this will disable the AWD system. If the jerking stops with the fuse enplace then the problem is the clutch pack.

Always run matched tires on an AWD Subaru. Make sure even the tire pressure is to specs.

Another very slim possibility is a bad front CV axle. If the car still jerks in a turn with the fuse installed then the transmission is fine and suspect an axle problem.

Reply to
johninky

Found a photo of this transmission. The housing over the black crossmember contains the clutch pack. Just have to remove a few bolts and the puppy just falls off.

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Reply to
johninky

Most likely you are experiencing 'torque bind' (though a second opinion to rule out bad U-joint or other issues is advised) due ,perhaps, to a wet clutch pack going bad.(assuming you have an automatic tranny)

You should confirm that all the tires on the car are the same type and have the same amount of wear. A new or mismatched tire mixed in can cause torque bind.

I THINK 97 is in the year range that may have had an aluminum tranny part (seat or sleeve???) that was changed to steel in later models.

Carl

Reply to
Carl 1 Lucky Texan

Johninky and Carl have covered two bases. Now for another option Go to the ford dealership and buy a bottle of "Friction Modifier", Ford uses it in rear ends. Now I have to check in with the techs at the shop- I believe you want to put it in the ATF, but may be the ft diff. does miricals, and have seen it cure several subarues. I'll post back tommorow with more. Steve

Reply to
S.Hansen

When the transmission fluid was "serviced" was it drained and filled or power flushed? Depending on the history, power flushes can be very detrimental if they were never done and then @ 125K the first power flush is done. The theory is that a bunch of crap is suddenly stirred up under the power flush. Anyway, a similar thing happened with my 98 legacy. I had it "power flushed" at 80K or so and experienced the same "shudder" at low speed and tight turns. Another poster recommended a $10.00 bottle of "lubegard ATF" additive. With the alternative being a $900 tranny job I put the pint of lubegard in the tranny. It worked like a charm. That was 5 years ago and the sub is still running strong at 150K+ miles. Here's a link for the stuff - I had to go to a local garage to get it.

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good luck!

Djay

Reply to
djay

Toyota now recommends GM... :(

Reply to
Hachiroku

Passenger: I had the transmission fluid and screen serviced March 6,

2009.
Reply to
NewsGroupie

It is definitely "torque bind." Good news, it can be repaired. You just have to find a tech who knows why and how to repair. Anyone who has serviced Soobs for 10+ should know. I have a friend who did my daughter's '95 Impreza two yrs ago and it's still fine.

MZ

Reply to
MZ

Thanks for the info. I don't suppose your friend lives in the Philadelphia PA (USA) area...does he?

Reply to
NewsGroupie

Thanks for the info. I don't suppose your friend lives in the Philadelphia PA (USA) area...does he? Buddy, save yourself some time, get the ford friction modifer and put it in the auto trans (the problem occored after the trans flush right?) Hint. I work at a subie shop. We keep it readly available. Had a used car giving issues, put some in and drove it in circiles, problem fadded away.

Reply to
S.Hansen

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The problem began LONG before the transmission service. I will try the ford friction modifier. Thank you

Reply to
NewsGroupie

It will go away for a short period, actually even without the anti-friction juice, by just driving it in circles. But eventually the binding will return and it will actually be dangerous when it does because it is worse and can prevent turning. Find someone who knows the problem and can perform the repair. Sorry, my friend is in Nova Scotia - lol. If you find someone who is competent (not just confident) I can ask my friend to describe the fix in an email. MZ

Reply to
MZ

This friction modifier won't prevent the AWD from working will it? I mean, the wet clutch pack will still transfer torque to the rear as before right?

Carl

Reply to
Carl 1 Lucky Texan

It will make it work like new.

Reply to
clare

Is this AT or MT?

If it's MT, often just getting new tires and an alignment will solve the problem

Reply to
Dominic Richens

no, won't do much else. I'm in Subaru school this week, (manual transmissions) I'll quiz the instructor and other tech's tommorow on the hows and why, and if the instructor knows more about this.

Reply to
StephenH

Talked with the instructor, the friction modifier was a authorized Subaru fix in the early 90's, but sense then modifications in the clutch plates it is not done anymore. That is the official Subaru standpoint. On my car, I would try it first rather than run to a transmission shop.

Reply to
StephenH

What are the possible long-term affects of torque-bind? Is this a real problem or just something that sounds bad once in a blue moon in an extreme situation? If it were a safety issue (steering lock-up problems) it would have created a major recall and/or class-action suit. If it is causing prematurely worn or damaged parts then I'm guessing the engineers at Subaru would have been instructed to correct it sometime in the last 10 years. Is it possible one could be doing more damage by increasing the slip and reducing the tourqe on the front end? I know it feels like it at times, but I have never had to turn the wheel hard and drive in circles on paved parking lots for extended periods of time. The closest I come to this is on old forest trails - but the dirt/grass/gravel allows the inside wheel to slip. I think I like the extra torque on those wheels in those situations. Maybe it is another reason why Subaru's don't get stuck very often.

How many people out there have had real problems because of this and not just conjecture or hearsay? What was the cost of repair and how many miles were on the car?

Am I going to see a special on Fox news about the lurking dangers of Japanese imports? Will it make Beck cry again?

Talked with the instructor, the friction modifier was a authorized Subaru fix in the early 90's, but sense then modifications in the clutch plates it is not done anymore. That is the official Subaru standpoint. On my car, I would try it first rather than run to a transmission shop.

Reply to
4orrester

Subaru recommends no more than 1/4" difference in CIRCUMFERENCE between the tires. Now, how long/how severely can that be violated to damage or affect length-of-service of driveline parts? Who knows. But it is a legitimate concern (perhaps to varying extent) with ALL AWD and any 4WD vehicles when on dry pavement. The primary component that will be damaged is the center diiferential/clutchpack in the transmission. AWD and 4WD are 'performance' features and require a little more knowledge/care by the consumer. I once heard of a lady that had her vehicle in 4WD and was trying to parallel park. The jeep became immobilized and had to be jacked up on one corner to 'unwind' the drive train and allow the hubs to be unlocked/w'ever.

Is

Certainly under most off-road conditions as well as weather induced poor traction situations on pavement, there is enough slippage to prevent binding from occuring.

You can find plenty of examples by searching. try

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carl

Reply to
Carl 1 Lucky Texan

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