vibration @ 30-40 then stops

drumnerd33 · #1 03-22-2011, 09:21 AM

ok i have been on here for a while trying to figure this out and have read many threads on vibration, but im not sure if mine is the same or not. everybody keeps talking about binding and i thought mine was just a driveline vibration cuz thats what it feels like, i did have bad u joints so i replaced all the u joints and still have my vibration.

i am new to the svx, i bought this one from a guy in denver colorado who was just going to junk it because he couldnt fix it and people werent offering him enough to buy it. so i got the car with a bad trans axle, the spiders were blown in the front diff. so i decided by doing research on here that i should do the 4.11 conversion, so i got the legacy tranny (with 4.11 did confirm this) and the outback diff (with 4.11 confirmed also and i did the carrier swap).

the car ran great, nice and smooth but did have the slow shift in 3rd gear so disconnected the resistor for firm shifts for now... gonna order shift kit... then after about 2 weeks i started getting the vibration, i installed the fwd fuse and it does go away.

so my question is i have the awd clutch basket off the stock tranny, should i pull it and see how it looks? and how do i check the solenoid c? and would the solenoid c even be my problem? cuz i dont seem to have any binding at slow turns or anything like other people were saying just a vibratrion @ 30mph-40mph plus a whirrr noise at my shifter.

drumnerd33 · #2 03-22-2011, 09:47 AM

sorry for long post.... to simplify i get vibration starting at 30 mph and is a pulsating vibration, then stops at around 40 mph. it happens under load when i let off the throttle it goes away.

nexus_7 · #3 03-22-2011, 03:19 PM

I had a hair line fracture on one of my axles once that caused something like that. Probably not what you have though.

92snowmachine · #4 03-23-2011, 04:12 PM

haven't seen it on svx but it's really common on foresters because the center bearing support for the rear driveshaft wears out. just something to check

drumnerd33 · #5 03-23-2011, 04:15 PM

checked the center bearing, rubber looks good and spins freely with no noise or feeling of wear.

drumnerd33 · #6 03-23-2011, 04:16 PM

also noticed i have some tranny fluid leaking out the rear seal and dripping on the exhaust. dont know if its related or just need to change the seal

92snowmachine · #7 03-23-2011, 04:20 PM

if the rear tranny seal is leaking, try replacing it but also see if you have excessive play in the driveshaft wear it goes into tranny, sometimes that bearing in the tranny goes bad, sometimes the shaft is worn, or sometimes you just have a 20 year old seal

drumnerd33 · #8 03-23-2011, 07:23 PM

ok thanks i will check that tomorrow.

drumnerd33 · #9 03-23-2011, 10:03 PM

92snowmachine i just noticed you are in denver. i actually got this svx from up there im in the springs. is there any groups that get together around here?

thumper_svx · #10 03-24-2011, 11:41 AM

I love this community. I came here thinking I would post on an identical issue with my 96 (144K miles). I have only had this happen twice to me, both times on the same stretch of road... but the road itself is fine because I drive it every day. Seems to be a very specific set of circumstances; slight uphill gradient, under about 3/4 power and between 30-40mph.

I guess I'll have to check my drivetrain. I do have a Forester transmission (4.44, baby!) so I wonder if they switched out the center support bearing as well with the one from the transplant. Guess I'll check that next time I have her in the air

drumnerd33 · #11 05-13-2011, 11:09 AM

well finally figured it out.. first of all i started getting a clicking noise from the bell housing. pulled the tranny and yup sure enough broken flex plate, thought maybe that was the vibration.. nope fixed it and vibration still there. so i talked to the drivline shop here in the springs and they said sounds like it could be out of balance so brought it in and sure enough it was way out of balance and now my vibes are gone runs nice and smooth now.

Sean486 · #12 05-13-2011, 12:33 PM

Quote:

Originally Posted by drumnerd33

well finally figured it out.. first of all i started getting a clicking noise from the bell housing. pulled the tranny and yup sure enough broken flex plate, thought maybe that was the vibration.. nope fixed it and vibration still there. so i talked to the drivline shop here in the springs and they said sounds like it could be out of balance so brought it in and sure enough it was way out of balance and now my vibes are gone runs nice and smooth now.

I have a vibration and a hum above 60mph on my 4.44 transmission. It seems like it is coming from the rear, but I wonder if it could be out of balance like yours?

drumnerd33 · #13 05-13-2011, 01:47 PM

well a hum sounds like in the differential or wheel bearing. unbalanced drive shaft doesnt really hum it just causes vibration, now i did get a noise every now and then from the vibration in my shifter but it wasnt a hum. first of all does it hum always or does it change on or off throttle? typically if it goes away on throttle and hums off throttle your backlash has opened up and you need to check your differential. if it always hums it could be a wheel bearing which the hum pitch should change in cornering and you should be able to tell which side of the car its coming from

drumnerd33 · #14 05-13-2011, 01:54 PM

when you put your 4.44 gears in the rear diff did you check the backlash and pattern? how long has it been humming, since you did the swap or just recently?

Sean486 · #15 05-13-2011, 02:15 PM

Quote:

Originally Posted by drumnerd33

when you put your 4.44 gears in the rear diff did you check the backlash and pattern? how long has it been humming, since you did the swap or just recently?

It has been doing it since I had the swap done, but only at 60+ mph. I didn't do the swap myself, but I know it is definitely a 4.44 gear pattern. Can any decent shop check the backlash for me?