Differential Problems? Grinding sound when turning slowly

[409industries]

Car: 2004 WRX STi (out of warranty)

Let me get this out of the way. "check that your DCCD is in auto!" It is.

So over the weekend we had quite some fun out in the desert doing lots of dounts and practicing rallycross. I was expermenting with many different DCCD settings all day. It wasnt until i was on hard pavement that I noticed my car was vibrating / grinding when making low speed full lock turns. Like the turns you would make to back a car into a parking spot. Is this a differential problem? I cant isolate if its coming from the front or the rear of the car.... maybe the center diff?

Oh and heres the real kicker. It doesn't do it right away when i take the car out for the first time in the morning (after its cooled down / sat overnight). Its almost like something heats up and then it starts having this problem.

Things Ive tried:

DCCD is in Auto
Front Tranny / Diff fluid is full of Motul Gear Oil

I'm trying to get some time to get this car over to a shop for someone to take a look at it. Im trying to avoid dealerships all together. At least i had a !$!@ing good time breaking my car:

http://www.dirtyimpreza.com/hosting/imagehosting/aaron_diotm_6-07.jpg

:( :( :( any help is much appreciated.

[I Like It Sideways]

I dont know what to tell you...
Maybe have someone outside the car check the inside tires while making a full lock turn... see if the inside tire is chirping a bit... just to see if thats where your shuddering problem is coming from.

Grinding.... as in...the sound of gears grinding?

[subyspawn]

mine does that from time to time after a rally-x. usually only a couple of times then it stops. i dont know what it is.

[409industries]

mine does that from time to time after a rally-x. usually only a couple of times then it stops. i dont know what it is.

Another buddy of mine (who goes out to the desert with me just about every time) is saying that his car is doing the same thing as well. Im suprised i've never heard of this happening before. I am concerned, but at the same time the car is still driveable. Especially on freeways, etc where steering is at a minimum.

Im going to swap out all the diff fluid (front and rear) and clean everything on the under carriage real good (stuff that may have gotten wedged up between the steering componenets and the skidplate. I also noticed mud in f-ked up places like jammed in the springs of my struts, under the control arms, etc...

[lorenkb]

That sucks Aaron. Although I can't really see how it would cause the symptoms described, I'd give the underside of the car a thorough washing just to make sure. My "diff clunk" went away along with all the mud... that stuff was like concrete!

Loren

[409industries]

That sucks Aaron. Although I can't really see how it would cause the symptoms described, I'd give the underside of the car a thorough washing just to make sure. My "diff clunk" went away along with all the mud... that stuff was like concrete!

Loren

Very good advice Loren, and something that i am going to do tonight. This week has been so busy, i was only able to get to the sheet metal on top after last saturday!!! I am hoping that the good fortune you had with the mud coming off will be the same as me. I'm mentally preparing for the worst though.

-Aaron

[409industries]

So i drained the rear diff, and to my relief the plug was clean. not big debris to speak of. I had been advised to use some heavy duty racing gear oil in the diff since i abuse the hell out of my car (Torco RGO 85w140).

The same guy that recommended this fluid saw that the rear CV's were popped out a bit, we snapped them back in, but it was still making noise.


The new fluid is in there now and everything appears to be doing ok. Ill have to double check after really pushing on it in the next few days but I am relieved i dont need to buy a new diff!

[409industries]

Update. that noise came back so i took my car to my buddy that knows his ****.

We drained the rear diff (yet again) and filled it with this:

http://www.cuscoracing.com/img/products/oil_lsd-r.gif
L.S.D. OIL 80W-140
For rear L.S.D which is exposed by high load and heat with high performance engine, tire and suspension. Fit for 4WD rear L.S.D & FR rear L.S.D. Also good for use in High temperature region and Hot Summer. For all mechanical L.S.D.

This stuff did the trick. ill be using it from here out. I think the reason why the Torco stuff was still chattering is that it doesnt have the friction modifiers in the actual gear oil for the LSD. You have to get the Limited Slip Friction Modifier Type F additive, and its not easy to find. i actually have some on order coming to my house, but hopefully if everything is good to go now, i wont need it..

[subyspawn]

good to hear... see you at JV?

[409industries]

Drove the car again today. No problems (aside from the wheel bearing going bad, but thats another story). I will be out at JV in full force.

Oh and i bought some subaru propaganda that will be accompanying me out to the even too... Gotta represent... youll see :) :) :)

[THE RETARD]

It might be the fact that is heavier weight oil your using now?after it warms up it looses its thickness,(like the other oil you had)
I think its your gears inside taken a poop,only when you turn right? specially being our cars are All time AWD.

[MBasile]

perhaps dirt got into your tophat. one time when I removed my tophat I forgot to but that concave washer back in on the front strut and when I turned slowly it made the worst sounding noise ever.

[409industries]

To recap...

the car is running great now (aside from the brake pads needing to be replaced and possibly the rotors...+ i need an alignement *sigh*)

When i was having this problem, i drained the rear diff, also the transmission / front / center diff fluid. All of these emptied clean, no big metal shavings, or shrapnel.

Taking the advice of my buddy that is very familiar with LSD's (they build D1 drift cars) I refilled the rear diff with the Cusco LSD oil 80w140.

http://www.cuscoracing.com/img/products/oil_lsd-r.gif

L.S.D. OIL 80W-140
For rear L.S.D which is exposed by high load and heat with high performance engine, tire and suspension. Fit for 4WD rear L.S.D & FR rear L.S.D. Also good for use in High temperature region and Hot Summer. For all mechanical L.S.D.

This stuff is fantastic. If you have the extra money (this **** is by NO MEANS cheap) and you really care about your suby then its probably worth getting it. At least for the rear diff. The center/transmission i just have redline in for now.

So far so good! :fingers crossed:

[timesnap]

Here may be the best article ever written on cusco lsd oil..... lol

http://www.geocities.co.jp/MotorCity/3349/lsd/elsdoil.html

[409industries]

6 months later and the noises are still gone. +1 for Cusco LSD oil. 80w-140. w00t!

[UP2MTNS]

Here may be the best article ever written on cusco lsd oil..... lol

http://www.geocities.co.jp/MotorCity/3349/lsd/elsdoil.html


huh?

At once, Oil for L.S.D. made by CUSCO is recommended in L.S.D. made by CUSCO.

[lorenkb]

Here may be the best article ever written on cusco lsd oil..... lol

http://www.geocities.co.jp/MotorCity/3349/lsd/elsdoil.html


huh?

At once, Oil for L.S.D. made by CUSCO is recommended in L.S.D. made by CUSCO.

Engrish mother******, do you speak it?

[409industries]

Here may be the best article ever written on cusco lsd oil..... lol

http://www.geocities.co.jp/MotorCity/3349/lsd/elsdoil.html

Im pretty sure the *LOL* indicated that was sarcasm. :) I think a 3 year old could write better...

[lorenkb]

Reading web-based translations is so much fun though!

[mattjaro]

if this is in the wrong thread please direct me to the correct one, but does anyone in this thread have info on replacing a front axle or know where i can find said information? i was out at el mirage and i munched up my axle, then drove back to pomona on said axle so its completely destroyed and needs replacement. also does anyone know if an 03 wrx axle would fit on a 04 wrx thanks for any help

[04trailsti]

i have the same problem and yea its freaks you out when you think your tranny is goin to fall out fo your car. At first it was only doing it when i had the diff in full lock. but that sound normal because just like a 4x4 truck you get wheel hop while turning full lock at slow speeds and some subby techs told me thats normal. a little while ago i did the grimspeed tranny cocktail which was suppose to be awsesome for tranny adn rear diff but then i found out that its not so good and then my car started dion the same thing in "auto" so right away i am definatly changing to extra S and subaru LSD gear oil. hopefully thats the problem solver

[wr-ecks]

mine does it too, so does my friends. iirc it says something in the owners manual about how this was normal and part of normal operation. every time i rallyX or do a little bit of "spirited off road driving" i notice it, it goes away quickly.