werid low RPM vibration

[Jon]

So about 2 months ago I started getting a vibration between 1500 and 1750 rpm, mostly when taking off. It's hard to pin point a location being in the car because it sounds as if it's coming from different areas whether i'm turning left, right, or just going strait.

I thought at first it was the DP banging off the tranny cross member. When i put my UP in, i didn't reattactch the DP bracket back and figured it was loose, but after getting it bolted back up, the noise is still there.

The vibration sounds like it's coming from a little farther forward from where the DP comes down, in front of the cross member. If i have the car moving at 1000 rpm in first or second gear and I give it gas, it makes the vibration as it passes 1750 rpm ONLY. I can't get it to make it constanly either by holding hte brake where it does it either.

I have no idea where the vibration could be coming from. I looked all over the tranny today and didn't see anything where it could be coming from. The only tight place is the DP and the cross member and it's not coming from there. Is there anything inside the tranny that could be shot? What are symptoms of a front diff failing?

[Bu11dogg2]

If a front diff starts to fails it makes a knocking noise.


Did you get a new clutch yet?

If so..

Try upgrading your tranny and engine bushings.

[ValuePack]

A touch more info would be helpful. Do the vibes change with the RPM or is it a steady feel throughout? Is it there both in neutral revving and under load(I'm guessing yes, since you express concern about the diff)? Worse at any particular road speed when underway?

+1 for mounts being a possibility, the stockers leave something to be desired, even when new. Group Ns are your friend, if you go that route.

I've also had a few FWD/AWD cars with a slight wobble/vibe from worn CVs and propshaft joints.

Happy hunting!

[Jon]

I haven't done the clutch yet. I'm going to do the engine mounts soon and already have a tranny mount in it.

The vibration is only when taking off or at very low rpm in first and sometime second gear. It's not something that sticks around, just a quick rumble. sounds just like an exhaust rattle. again, only at 1750 rpm. If i take off at a higher or lower rpm, there is no sounds at all, only 1750.

If i turn right and take off, it sounds like it's coming from the drivers side, turning left makes it sound like it's coming from the pass side, but then again, that might just be me and the way i move around in the car.

I don't know what else could be making the noise. Next thing i'm going to try is taking the griffin top mount off and putting my stock top mount back on. maybe it's hitting something and it just sounds like it's coming from lower in the engine.

[ValuePack]

I'm cautious to say it, but how's about heat shields? Do you still have the stockers? Start simple: get under the car with big hose clamps and see what can be bent and compressed. You may be amazed... I've heard loose stock heatshields that sound like everything from a low hum to a chainsaw at WOT with no oil.

Just an idea.

[Jon]

nope, no heat shields anymore, just wrap on the UP and DP. I'll get under it again tomorrow and look some more as well as change out the intercooler.

[Jon]

It also seems to get more pronounced as the car warms up. I drove it today for about 10 minutes and it hardly did anything. Yesterday after driving it all day, it was terrible.

[Iheartsubarus]

and you wanted to sell me your car... shame.

[Jon]

it didn't have anything wrong with it then...

[Iheartsubarus]

but now it does..

[-=The Boss=-]

but now it does..
demand a lower price :rofl:

[Jon]

10K and it's your sis...

[Iheartsubarus]

You know I would if I could.

10K and it's your sis...

[Jon]

well i swapped out the griffin top mount for the stock one and i haven't heard the vibration since. Must have been rubbing on something. I'm going to drive around today and see if it'll still do it.

[Bu11dogg2]

do you have a strut tower bar?

Check to see if it's rubbing on the intercooler vice/versa

[Jon]

nope. i think it might have been vibratiing on the tranny dip stick. I have a home made heat shield on the turbo and had to bend the dip stick in the other direction and that might have been rubbing on the STi Y pipe on the griffin. That, or the front of this griffin was vibrating on the drivers side mount because it didn't have a bolt in it. Whatever it was, it's not doing it anymore.

[Service@ExeterSubaru]

rattles are no fun

[kgj996]

My exhaust is too loud to hear my rattles. :lol:

[Robk0000]

occasionally, my car pulls to the right and the steering wheel vibrates pretty hard only happens during deacceleration too. Happened about 2-3 times in the last 3 months

[SubyFr3ak]

My exhaust is too loud to hear my rattles. :lol:
+1