NoahDL88 Posted November 29, 2006 Share Posted November 29, 2006 I have a friend that just bought a 95 Legacy AWD, and he had to put chains on it to get out of his driveway, which is unacceptable, with AWD he should have had absolutely no problems. Can the duty C solenoid get stuck in the "2wd" position? cause thats what were thinking, at least after we've ruled out the option of the FWD fuse being in. Quote Link to comment Share on other sites More sharing options...
porcupine73 Posted November 29, 2006 Share Posted November 29, 2006 Or the clutch packs might be really worn out? Quote Link to comment Share on other sites More sharing options...
idosubaru Posted November 29, 2006 Share Posted November 29, 2006 FWD fuse was checked already or you need to check it still? Check that the circuit isn't shorted as well. Probably Duty Solenoid C or clutch pack related is my random guess. The transmission light isn't blinking? Quote Link to comment Share on other sites More sharing options...
jamal Posted November 29, 2006 Share Posted November 29, 2006 Maybe he just has junk tires? The AWD in that car has open front and rear diffs and the center can't transfer all of the power to the front or rear. This means it will spin one front and one rear tire if it's really slippery. Quote Link to comment Share on other sites More sharing options...
nipper Posted November 29, 2006 Share Posted November 29, 2006 possabilites, junk tires, but then front and rear sshould spin. My guess is that the clutch pack is so badly worn that it no longer transfers power. Duty C fuse kills the AWD, it does not engage it. Duty C solenoid is probably working well. Sounds like its time for a rebuilt AWD unit. Failed duty c will give constant 50/50 split. nipper Quote Link to comment Share on other sites More sharing options...
Slegacy96 Posted November 29, 2006 Share Posted November 29, 2006 What transmission? Quote Link to comment Share on other sites More sharing options...
nipper Posted November 29, 2006 Share Posted November 29, 2006 What transmission? Well if they ruled out the the fuse, i would suspect an automatic. In a manual you never get 2wd in a failure, it fails in full TB. nipper Quote Link to comment Share on other sites More sharing options...
Slegacy96 Posted November 29, 2006 Share Posted November 29, 2006 I ask because my understanding that is with Continous AWD (found in manual transmission vehivles) the center diff. can essentially wear out since it is fluid based. Which I dont know much about, so is there anyone who does know about such an occurence? We had been debating on LGT.com and never found an answer that made sense. Someone said you go well past 200K another said 50k, which would just be silly. Im at 87k and my AWD appears to working just fine Quote Link to comment Share on other sites More sharing options...
nipper Posted November 29, 2006 Share Posted November 29, 2006 I ask because my understanding that is with Continous AWD (found in manual transmission vehivles) the center diff. essentially wear out. Which I dont know much about, so is there anyone who does? We had been debating on LGT.com and never found an answer. Someone said you go well past 200K another said 50k, which would just be silly. Im at 87k and my AWD appears to working just fine MEMEMEME this isnt hard to understand. Just because a car is awd that does not mean it has the same system as the others. SOme systems arent worth the cost. Automatics do not have a center diff (do a search youll find tons of info). Automatics have a clutch pack that is specially designed to allow for some slipping. The duty c (isnt this a sticky yet) Regullates between a 10/90 to 50/50 split by cycling on and off. The spool valve regulates how much pressure is applied to the clutch (duty colenoids always cycle). What wipes out the AWD on the automatic is (in this order) Mismatched tires (even more true for manuals), failed duty c solenoid (failed solenoid will give constant 50/50 full pressure AWD), Dirty tranny fluid (reversable) ignoring the tranny temp light. Pre 1997 1/2 trannies had a design faul;t where the seals leaked internally and would apply the AWD all the time. The system will last the life of the car if taken care of, but it seems that wearing out after 180,000 miles is just like anything else on a car that old, that its just worn out. I dont see how it is so hard to find the information, just google it. nipper Quote Link to comment Share on other sites More sharing options...
NoahDL88 Posted November 29, 2006 Author Share Posted November 29, 2006 junk tires, My guess is that the clutch pack is so badly worn that it no longer transfers power. Don't know about the fuse, will find out tomorrow he's got some crummy summer tires that came with the car, which could easily be the problem. Will a clutch pack AWD duty "C" bit work from a 92 legacy, and has anyone replaced this? is it an easy job, or should we just start looking for a new tranny? Quote Link to comment Share on other sites More sharing options...
Slegacy96 Posted November 29, 2006 Share Posted November 29, 2006 MEMEMEME this isnt hard to understand. Just because a car is awd that does not mean it has the same system as the others. SOme systems arent worth the cost. Automatics do not have a center diff (do a search youll find tons of info). Automatics have a clutch pack that is specially designed to allow for some slipping. The duty c (isnt this a sticky yet) Regullates between a 10/90 to 50/50 split by cycling on and off. The spool valve regulates how much pressure is applied to the clutch (duty colenoids always cycle). What wipes out the AWD on the automatic is (in this order) Mismatched tires (even more true for manuals), failed duty c solenoid (failed solenoid will give constant 50/50 full pressure AWD), Dirty tranny fluid (reversable) ignoring the tranny temp light. Pre 1997 1/2 trannies had a design faul;t where the seals leaked internally and would apply the AWD all the time. The system will last the life of the car if taken care of, but it seems that wearing out after 180,000 miles is just like anything else on a car that old, that its just worn out. I dont see how it is so hard to find the information, just google it. nipper Yes, but I wasnt really asking about the auto. Ive got all this Active AWD System: Active all-wheel drive is a term coined by Subaru to differentiate the all-wheel drive system in the automatic transmission (4EAT) from other "reactive" all-wheel drive systems on the market today. What makes this all-wheel drive system so special is its ability to anticipate traction needs and act before a wheel slips. The mechanism that transfers torque fore and aft is contained within the transmission’s tailshaft. To the casual observer it looks just like a typical hydraulic clutch found in any automatic. The key difference in this clutch pack is its operation. It’s designed to slip according to how much all-wheel drive is needed. When an automatic’s clutch slips, it is due to a malfunction and will eventually burn up. But the multi-plate transfer (MPT) clutch uses a special friction material that easily withstands the friction loads generated during torque transfer. (Also referred to as VTC = Variable Transfer Clutch) The MPT’s operation is controlled by the Transmission Control Unit (or TCU) and constantly changes dependent on how the vehicle is being driven. To get more all-wheel drive, the TCU increases the hydraulic pressure to the clutch for less slippage. Less all-wheel drive calls for more slip and the TCU reduces the hydraulic pressure to the clutch. Quote Link to comment Share on other sites More sharing options...
nipper Posted November 29, 2006 Share Posted November 29, 2006 Don't know about the fuse, will find out tomorrow he's got some crummy summer tires that came with the car, which could easily be the problem. Will a clutch pack AWD duty "C" bit work from a 92 legacy, and has anyone replaced this? is it an easy job, or should we just start looking for a new tranny? er um You may find it easier to just replace the tranny. Its a job you can do, but its not something you want to use used parts in. Its like putting a used clutch in your car, you can do it, no one does, and its a waste of time. You need new parts. nipper Quote Link to comment Share on other sites More sharing options...
Slegacy96 Posted November 29, 2006 Share Posted November 29, 2006 And a 10/90 split in the 4EAT? So why does the 5EAT system (found in the latest LGT) have a 45/55 split. Wouldnt the car with more power, be more likely to have a greater RWD bias? or was the a typo? Cause I just realized what I wrote (its late gimme a break) and doesnt the 4EAT have a 90/10 split? Which would make more sense. Quote Link to comment Share on other sites More sharing options...
nipper Posted November 29, 2006 Share Posted November 29, 2006 Yes, but I wasnt really asking about the auto. Ive got all this Active AWD System: Active all-wheel drive is a term coined by Subaru to differentiate the all-wheel drive system in the automatic transmission (4EAT) from other "reactive" all-wheel drive systems on the market today. What makes this all-wheel drive system so special is its ability to anticipate traction needs and act before a wheel slips. The mechanism that transfers torque fore and aft is contained within the transmission’s tailshaft. To the casual observer it looks just like a typical hydraulic clutch found in any automatic. The key difference in this clutch pack is its operation. It’s designed to slip according to how much all-wheel drive is needed. When an automatic’s clutch slips, it is due to a malfunction and will eventually burn up. But the multi-plate transfer (MPT) clutch uses a special friction material that easily withstands the friction loads generated during torque transfer. (Also referred to as VTC = Variable Transfer Clutch) The MPT’s operation is controlled by the Transmission Control Unit (or TCU) and constantly changes dependent on how the vehicle is being driven. To get more all-wheel drive, the TCU increases the hydraulic pressure to the clutch for less slippage. Less all-wheel drive calls for more slip and the TCU reduces the hydraulic pressure to the clutch. well thats an auto, thats the 4eat, so i have no idea what your talking about. Manuals dont have computers. nipper Quote Link to comment Share on other sites More sharing options...
nipper Posted November 29, 2006 Share Posted November 29, 2006 And a 10/90 split in the 4EAT? So why does the 5EAT system (found in the latest LGT) have a 45/55 split. Wouldnt the car with more power, be more likely to have a greater RWD bias? or was the a typo? Cause I just realized what I wrote (its late gimme a break) and doesnt the 4EAT have a 90/10 split? Which would make more sense. that split is controlled in a fixed fashioned ny the viscous coupling. A viscous coupling is a bunch of alternating plates in silicon. Silicon gets thick as it heats up. The holes in the plates are calibrated to give a specific split. The differnce in speed in the plates shears the fluid, causing heat, and locks up the plates. I am not a subaru engineer so i cant tell you why they biased it the way did, but its a complicated decision. nipper Quote Link to comment Share on other sites More sharing options...
Slegacy96 Posted November 29, 2006 Share Posted November 29, 2006 well thats an auto, thats the 4eat, so i have no idea what your talking about. Manuals dont have computers. nipper I didnt say that they did. Quote Link to comment Share on other sites More sharing options...
Slegacy96 Posted November 29, 2006 Share Posted November 29, 2006 that split is controlled in a fixed fashioned ny the viscous coupling.A viscous coupling is a bunch of alternating plates in silicon. Silicon gets thick as it heats up. The holes in the plates are calibrated to give a specific split. The differnce in speed in the plates shears the fluid, causing heat, and locks up the plates. I am not a subaru engineer so i cant tell you why they biased it the way did, but its a complicated decision. nipper With more detail: Continuous AWD System: The manual transmission’s all-wheel drive is referred to as a continuous all-wheel drive system. It uses a center differential located inside the transmission case that is controlled by a viscous coupling device. In effect, the center differential is a limited-slip differential. In normal operation, power is distributed equally to the front and rear wheels. Plates are alternately attached to the front and rear output shafts inside the viscous coupling. When a rotational difference occurs between the front and back wheels, the plates inside the viscous housing shear inside the contained fluid (a type of silicone) heating it and causing the fluid to thicken. The thickened fluid causes the plates to transfer torque from those that rotate faster (the slipping wheels) to the plates that rotate slower (the wheels with the best traction). This no-maintenance system is simple, compact and virtually invisible in its operation. The system can distribute torque from a 50:50 torque split for maximum traction to mostly front or rear wheel drive. (Source: http://www.autoworld.com/news/Subaru..._All-Wheel.htm) A. Continuous AWD with Rear LSD: Available with 5MT on WRX, Legacy GT, Outback 2.5i, Outback XT and with 6MT on Spec.B B. Continuous AWD without rear LSD: Available with 5MT on Impreza 2.5i, Outback Sport and Legacy 2.5i Quote Link to comment Share on other sites More sharing options...
Slegacy96 Posted November 29, 2006 Share Posted November 29, 2006 I am not a subaru engineer so i cant tell you why they biased it the way did, but its a complicated decision. nipper Well why arent you? Quote Link to comment Share on other sites More sharing options...
nipper Posted November 29, 2006 Share Posted November 29, 2006 I didnt say that they did. but what you posted did, so now i am confused. Stay with one transmission and ask the question. Also the automatic is NOT 90/10. its 90/10 all the way through to 50/50. So if the computer wants to give you 76/24 thats what you get. nipper Quote Link to comment Share on other sites More sharing options...
nipper Posted November 29, 2006 Share Posted November 29, 2006 Well why arent you? im an automitve engineering technician, unemployed from a back injury still (grrrrrr). You think civil service is hard to get into, try cracking this field Quote Link to comment Share on other sites More sharing options...
Virrdog Posted November 29, 2006 Share Posted November 29, 2006 he's got some crummy summer tires that came with the car This IS the problem. No need to bother reading all the AWD system babble. If he has problems on dry pavement start looking at the transmission. :cool: Quote Link to comment Share on other sites More sharing options...
johnceggleston Posted November 29, 2006 Share Posted November 29, 2006 This IS the problem. No need to bother reading all the AWD system babble. If he has problems on dry pavement start looking at the transmission. :cool: i had a 61 chevy pickup that i got stuck on flat ground in wet grass one morning. i just popped the clutch too fast and i was stuck. so mistakes happen!! Quote Link to comment Share on other sites More sharing options...
Andyjo Posted November 29, 2006 Share Posted November 29, 2006 Noah, replacing the clutch pack & solenoid shouldn't be that hard, i've actually read that you can do it without dropping the trans, just disassembling the read end of the 4eat... I have to do the same thing w/ my impreza, lack of power to the rear end... can actually make the front end slip... The local tranny place near where i live in NH said they would do it for $400 bucks... but i still want to do it myself Quote Link to comment Share on other sites More sharing options...
Slegacy96 Posted November 29, 2006 Share Posted November 29, 2006 This IS the problem. No need to bother reading all the AWD system babble. If he has problems on dry pavement start looking at the transmission. :cool: But it wasnt problems on dry pavement. It was in the snow. Quote Link to comment Share on other sites More sharing options...
Slegacy96 Posted November 29, 2006 Share Posted November 29, 2006 i had a 61 chevy pickup that i got stuck on flat ground in wet grass one morning. i just popped the clutch too fast and i was stuck. so mistakes happen!! Agreed. Quote Link to comment Share on other sites More sharing options...
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