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This will probably sound as a dumb question to some on the board. I have had 4 Subaru's and have been well please with all of them.

 

My question! I have a 1999 Subaru Legacy that I just purchased. The driveway to my home is graveled, 1/2 mile long and real steep. My previous Subaru's would crawl the steepest parts of the driveway in #one or drive. My present one will spin out in #one or drive (especially if just rained) unless I give it a running start. What is the best way to check and see if the awd is working as it should? I don't think so compared to previous vehicles.

 

Thanks

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How many miles are on this car?

 

It sounds like the AWD may not be working (tired clutches).

 

One way to find out is to put the FWD fuse in the holder and see if there is a differnce.

 

Another way is to put the car in D1 and force the awd on (which D1 does)

and see what happens.

 

I have this feeling the clutches may be tired.

 

nipper

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I have noticed the same thing. I have a 95 Legacy and a 04 Forester (28,000 miles). The 04 will spin before the 95 will. I think it is just due to it having more torque or maybe the gearing is lower. Just have to go easier on the gas.

 

the legacy should be 4.11 gearing. if not 4.11, then 3.9. i'm not sure what the forester is, but i'm sure it's not hard to find out. also, i have the understanding that from a stop the mid 90's automatic models begin in a 60/40 split and move into a 90/10 split when a coasting speed is reached. i don't know much about the newer AWD systems from subaru, however i do know that my wife's cr-v with the "real-time" awd begins and runs with a 100/0 split UNTIL a slip occurs.

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i'm questionable about the force awd in 1st... force it to do what? 50/50? if that's the case, why doesn't the car hop like it does with the awd override switch that andyjo wrote up last year?

 

:horse:

 

Im going to just paste this someplace so i can cut and paste.

 

 

 

anyjo switch BYPASSES the TCU and directly controls the solenoid. The AWD unit is far more then just a solenoid. Its a specially designed clutch designed to tolerate a limited amount of slip in turns. It works in conjunction with the spool vlave inside the transmission that regulates the pressure. When you bypass the TCU and force the solenoid on with a switch, you are locking up the AWD without allowing the tcu to modulate the duty solenoid (rapidly shutting it on and off hence the name duty) to allow for 50/50 split and the differnential action. From somone watching the tires, you cannot tell the solenoid is rapidly pulsing.

 

You can be as questionable as you want about the forced 50/50 split, but its in the the subaru documentation that reverse and low, along with wide open throttle force the TCU to apply 50/50 torque split to the awd. This is controled, and not a full on.

 

http://endwrench.com/images/pdfs/4EAT.pdf

http://endwrench.com/images/pdfs/4EAatPh2Win04.pdf

 

The 99 operates basically as the same as the previous model, except where the changes have been noted in the 2nd article.

 

 

nipper

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Our MY95 Legacy always seem to have "tighter" AWD than our MY01 Outback Ltd.

 

I find myself using 1 & 2 to get the 50/50 more in the '01 for less front wheel slippage than in the '95.

 

I rented a 2006 for 10 days and took it off road a few times. I was disapointed in the lag for the AWD to to catch up from a dead stop (in drive), but it seemed fine on the go. It seemed like the calibration or something changed.

 

nipper

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:horse:

 

Im going to just paste this someplace so i can cut and paste.

 

 

 

anyjo switch BYPASSES the TCU and directly controls the solenoid. The AWD unit is far more then just a solenoid. Its a specially designed clutch designed to tolerate a limited amount of slip in turns. It works in conjunction with the spool vlave inside the transmission that regulates the pressure. When you bypass the TCU and force the solenoid on with a switch, you are locking up the AWD without allowing the tcu to modulate the duty solenoid (rapidly shutting it on and off hence the name duty) to allow for 50/50 split and the differnential action. From somone watching the tires, you cannot tell the solenoid is rapidly pulsing.

 

You can be as questionable as you want about the forced 50/50 split, but its in the the subaru documentation that reverse and low, along with wide open throttle force the TCU to apply 50/50 torque split to the awd. This is controled, and not a full on.

 

http://endwrench.com/images/pdfs/4EAT.pdf

http://endwrench.com/images/pdfs/4EAatPh2Win04.pdf

 

The 99 operates basically as the same as the previous model, except where the changes have been noted in the 2nd article.

 

 

nipper

 

i wasn't arguing, just questioning. but thats the clearest i've heard it explained.

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I wonder if a change in the AWD clutches or engagement from older to newer models delays or reduces the chances of torque bind over the life of the car????

:confused:

 

Well there have been some tweaks to clutches, and many more tweaks to the ECU. The new systems have multiple speed sensors, and even read the wheel speeds and applies individual brakes.

I dont think TB was a thought, as limp mode even in the phase II 4eat is fully applied AWD and third gear.

 

nipper

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