Is my diff going out?
#21
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Yeah... I'll make sure to do them in the driveway so I don't have to push it far when something grenades.
STravisVrooman, I'm pretty sure most people here know that it's the smaller 6 inch R+P that is weak point and that we upgrade to the larger 7 inch.
I'll be waiting for a deal to come around on a 4.10 Torsen swap so if any of you see one for 750 or less, a PM would be appreciated.
STravisVrooman, I'm pretty sure most people here know that it's the smaller 6 inch R+P that is weak point and that we upgrade to the larger 7 inch.
I'll be waiting for a deal to come around on a 4.10 Torsen swap so if any of you see one for 750 or less, a PM would be appreciated.
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A reply I recieved over at m.net about 6 months ago, when I asked the same thing about that siren sound. In repeated threads, synchronizer cones were always mentioned:
Driving issues. That noise is the gears/synchronizer cones in the trans spinning up to speed. Rev match your downshifts and you won't hear it anymore, but FWIW the noise is harmless. Not rev matching your downshifts wears out your clutch and, if done badly enough, can lock up your rear wheels and cause you to crash, especially if you do it in a corner.
Driving issues. That noise is the gears/synchronizer cones in the trans spinning up to speed. Rev match your downshifts and you won't hear it anymore, but FWIW the noise is harmless. Not rev matching your downshifts wears out your clutch and, if done badly enough, can lock up your rear wheels and cause you to crash, especially if you do it in a corner.
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Lol Kenzo, while what you describe is a valid source of noise (Yes I know what synchros spinning up to speed sounds like.) It is not the same. Mine makes this noise in any gear clutch in or out. Have you even watched the videos?
I rev-match every downshift. It's a habit and it's the only smooth way to do so with a lightweight flywheel.
Meh. Anyways I'd rather it be the tranny going out than the diff for some reason, just because it would be cheaper to replace immediately than doing a torsen swap. Tomorrow I'll check the tranny fluid level and for metal shavings.
I'm having second thoughts about not autocrossing it this weekend again.
I rev-match every downshift. It's a habit and it's the only smooth way to do so with a lightweight flywheel.
Meh. Anyways I'd rather it be the tranny going out than the diff for some reason, just because it would be cheaper to replace immediately than doing a torsen swap. Tomorrow I'll check the tranny fluid level and for metal shavings.
I'm having second thoughts about not autocrossing it this weekend again.
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Hokay, so my diff blew today. I got 7 runs in autocross with increasing noise near the end, made it 30 miles to within a mile of home on the freeway and then grindPOPgrindgrindgrind.
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Haha yeah I've got an oily mess on the back of the car too. Miataz, you don't have a turbo, that's why your diff still works, though there's always a chance.
There wasn't any immediate warning that the diff was going to go. I put 300 miles on it with that whining sound and other than that, for thirty miles there was a tiny click on the transition between accel and decel.
There wasn't any immediate warning that the diff was going to go. I put 300 miles on it with that whining sound and other than that, for thirty miles there was a tiny click on the transition between accel and decel.
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Long-needed thread update:
I must have mechanical empathy. The carrier bearing failed. The ring and pinion looked to be in pristine condition.
I found a low mile 3.9 Torsen out of an 02 6 speed to put in. I love the Torsen!
The inside tire scratching for traction in the turns and in gravel parking lots, the feeling of the rear end being much more planted coming out of a turn and more predictable when it's not planted is just amazing.
Other than that, I've got a new noise in the transmission now that I'll post a video of sometime. I'm not too worried about it though because a transmission is a whole lot cheaper to replace than getting a Torsen swap.
I must have mechanical empathy. The carrier bearing failed. The ring and pinion looked to be in pristine condition.
I found a low mile 3.9 Torsen out of an 02 6 speed to put in. I love the Torsen!
The inside tire scratching for traction in the turns and in gravel parking lots, the feeling of the rear end being much more planted coming out of a turn and more predictable when it's not planted is just amazing.
Other than that, I've got a new noise in the transmission now that I'll post a video of sometime. I'm not too worried about it though because a transmission is a whole lot cheaper to replace than getting a Torsen swap.
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Hustler, my diff is fixed, trans is making noise now. The whine changes with rpm. Sounds allot like the whirring noise in reverse except I get it in all gears.
The carrier bearing gutted itself when I pulled the driveshaft. Lots of exciting destruction of metal going on here.
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R+P were still good sans where the Pinion gear was allot to push against the VLSD when the carrier bearing finally blew out. That was probably all done during the 200 foot grind to a halt on the highway.
The carrier bearing gutted itself when I pulled the driveshaft. Lots of exciting destruction of metal going on here.
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R+P were still good sans where the Pinion gear was allot to push against the VLSD when the carrier bearing finally blew out. That was probably all done during the 200 foot grind to a halt on the highway.
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#35
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I found a low mile 3.9 Torsen out of an 02 6 speed to put in. I love the Torsen!
The inside tire scratching for traction in the turns and in gravel parking lots, the feeling of the rear end being much more planted coming out of a turn and more predictable when it's not planted is just amazing.
The inside tire scratching for traction in the turns and in gravel parking lots, the feeling of the rear end being much more planted coming out of a turn and more predictable when it's not planted is just amazing.
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