ddub

Ok... I had some pretty bad clunking for a while. Replaced diff mount with a solid one, replaced engine mounts with solid ones, replaced tranny mounts with solid ones, new driveshaft, go out to drive and it still remains! Mind you it is definitely not as bad as before or happen as often, but there still is some. During all of this I discovered 1 broken engine mount and 1 almost broken tranny mount and my driveshaft was kinda iffy.

Any ideas on what could be left to check!? I'm starting to think the remaining bit might be the exhaust hitting something, maybe.

Also, there was vibration but that is completely gone now, so I'm assuming the shaft fixed that because it was the last thing I replaced. And, the ORIGINAL clunking that started way long ago happened 2 weeks after I put in Redline SuperLight Shockproof diff fluid, might just be a coincidence but is it at ALL possible that this fluid is raping my differential? I'm contemplating replacing it with amsoil fluid...

Any help appreciated.

ilike2eatricers

Not sure about the shockproof, but I think Icemark uses it in all his cars. I used 75w90 redline and it's fine. Are you exhaust hangers for your catback pretty close to the gas tank? Mine seem like they are but then again I have RBs.

ddub

Yah I know Icemark does, that's where I got the idea I just thought it was a weird coincidence it started happening after that.

My exhaust is custom, uses the stock exhaust hanger/rubber things except for the one on each side where the hanger is welded to the rear tow hook.

ddub

Bump, throw out any ideas if you have them, or similar experiences/fixes =\

Sir Rupert Hobo

my RB muffler on the driver's side was tapping something... made a clunking noise like a broked diff. mount.

well, that's my experience

ddub

Yah I'm really thinking that's what it is. It sounds like its coming from the passenger side rear.

But I was just putting this out there to see if there is anything else anyone has had that was broken and caused clunking, thx for your input.

wargoblin

Is your drive shaft brand new? If not it probably is still the drive shaft. Mine has pretty much NO play in the U joint. But if I push enough up and down, I can feel how much it moves~ as little as it does. And it makes a loud clunk noise when I push in the clutch quickly. I have compitition mounts on the engine and tranny and an engine torque brace. Try buying a brand new drive shaft, I'm waiting until mine gets worse till I buy a brand new one.

andrew lohaus

its most likely slop in the differential itself. i replaced my diff mount and still had teh slop, then i got under the car and realized the driveshaft would rotate back or forth maybe 5-10 degrees before the gears in the pumpkin would "mesh" up and actualy start turnign the 1/2 shafts. my clunk developed after one exceptialy hard launch

far as i can tell the only remedy is to replace the diff with one that still has the proper backlash, or rebuild it and replaced whatever in there got f'ed up. just worn out......

ddub

In the first post it says it's a new driveshaft.

For those that want an update here, it's the half-shafts.

scathcart

Camber links are known to go and cause a clunking under changes from accel-decel and whenever the clutch is disengaged.
Check/replace them.

ilike2eatricers

What exactly about the half shafts? Also how much did a new driveshaft run you?

ddub

The u-joints on the half-shafts, where it connects to the diff, has clunky play up/down on both sides if I crawl under there and try to move em around.

Cost of the driveshaft was brand new from mazdatrix, aftermarket unit with replaceable u-joints. $248.20 whereas the stock one with non-replaceable (at leave very hard) u-joints is $375.75 I actually tried replacing the u-joints on my stock one first, didn't exactly work out haha.

andrew lohaus

yes, yes i know, im telling you the slop was
in the differential itself, but the only evidence of this was from the relative motion of the driveshaft and the 1/2 shafts. the slop was not in the yoke of the driveshaft or the cv joints, it was between the ring and pinion.

ddub

Differential is fine. It was having its own issues until I drained it and put in an LSD additive, after that half my problems went away.

ajsuper7

It could be the one of the cv joints?(where the axle shafts meet the diff), i broke one when i was 16 and everytime id go from a stop it would make a horrible sound in the rear.

ddub

Yah sorry, when I said "u-joints" on the half-shafts I meant cv joints. That was just my mistake/typo after a long hard day with a crazy *** midterm, I wasn't "all there" at the time

But yes, it is the CV JOINTS on the half-shafts that are fucked and have the play.