yep, but i got a gt so im not worried about the 28 spline for now.
Excessive driveline play/ is this the "cobra clunk" (videos inside)
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yep, but i got a gt so im not worried about the 28 spline for now.
))
Great to hear buddy
i have the clunking noise too, but i hear the noise coming from the front of the car, like where the trans is. not the rear end. ill have to go under my car and look at the driveshaft. but the noise that everyone hears, is it from the front or the rear of the car? (trans area or diff area?)
rear
ok. when my car is in gear and the parking brake on, i dont have any play in my driveshaft. when my car is in nuetral, i have plenty of play in the driveshaft. and the half shafts are not moving when i twist my driveshaft. it clunks and makes the same noise as in the movies at the beginning of this thread. i hear the clunking at the trans and the diff when im under the car but when im driving i hear it in the front. my car makes clunking when i put it into 1st from a stand still and then when im at low speeds in a low gear (i.e. 2nd gear at 10 mph or 4th gear at 30mph) it clunks when i let off the gas.
would it make any difference that my car isnt in gear?
would it make any difference that my car isnt in gear?
opened up my old differential and turned out the problem was too much backlash and the pinon had too much play by the flange. everything else was great.
p.s. turned out I had 355 gears in it with carbon clutches and Ected Electronic locking differential lol
p.s. turned out I had 355 gears in it with carbon clutches and Ected Electronic locking differential lol
I have a loud banging that sounds like it comes from the transmission as well. Really it is driveline slack but it is loud and shakes the car when you really slam it (i.e. release the clutch quickly).
I've had my Diff apart twice from two different people and each time it was put back together with rebuild kits and the problem persists. 3.73 gears, tru trac, lpw cover, etc...
Is it possible that the issue is the diff housing or the trans? I can't imagine it being the trans as that should not have enough play to cause a banging sound. When you turn the DS by hand you can see it has too much play which is what causes the bang noise.
i.e. engage clutch and the slack lets up once the driveline is engaged resulting in a solid bang.
I'm about to the end of the line on the IRS. Last resort might be buying a new diff case (internals are all good). I even went to a solid collar during this last rebuild.
I've had my Diff apart twice from two different people and each time it was put back together with rebuild kits and the problem persists. 3.73 gears, tru trac, lpw cover, etc...
Is it possible that the issue is the diff housing or the trans? I can't imagine it being the trans as that should not have enough play to cause a banging sound. When you turn the DS by hand you can see it has too much play which is what causes the bang noise.
i.e. engage clutch and the slack lets up once the driveline is engaged resulting in a solid bang.
I'm about to the end of the line on the IRS. Last resort might be buying a new diff case (internals are all good). I even went to a solid collar during this last rebuild.
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Ok, I was asked to offer my opinion on this issuse. First off, if all the bushings are in good condition and all the mounts/ bolts are torqued to spec, then the problem is a collasped crush shim or too much backlash or both.
The rear housing must be removed, and torn down. It must be rebuilt with a housing spreader, the reason is it must be opened up 0.030" to compensate for the aluminum housing expansion when hot. Also it must be rebuilt with a solid shim spacer and NOT a crush shim. I like this one: 1986-11 Mustang 8.8" Super Shim Kit at LRS - Same Day Shipping! The reason is becasue during hard launches or acceleration it can collapse the crush shim more and that will change your backlash.
I can't tell you how may times I see Cobra IRS diffs set up wrong from the "Pros who do this all the time on SRA"
Just my $0.02 for what it's worth. Good luck!
The rear housing must be removed, and torn down. It must be rebuilt with a housing spreader, the reason is it must be opened up 0.030" to compensate for the aluminum housing expansion when hot. Also it must be rebuilt with a solid shim spacer and NOT a crush shim. I like this one: 1986-11 Mustang 8.8" Super Shim Kit at LRS - Same Day Shipping! The reason is becasue during hard launches or acceleration it can collapse the crush shim more and that will change your backlash.
I can't tell you how may times I see Cobra IRS diffs set up wrong from the "Pros who do this all the time on SRA"
Just my $0.02 for what it's worth. Good luck!
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It has a solid shim spacer...I need to send you my diff...
No prob, just PM me your info. I'm outa town for a few days but when I get back I can respond to your PM and you can ship out the diff if you like. We will get it sorted out.
I have the same excessive play in my cars driveline also. I guess it's normal alot of other members have it also on this board.
I believe this is the issue. It would be interesting to see how many people who have similar driveshaft slack as the OP also have a crush shim. I have a feeling mine was rebuilt with a crush shim and it has collapsed over time. It definitely isn't bushing related as i have all the FTBR bushings. There is no sound when the diff is loaded in either direction but when i'm driving in stop and go traffic, i can hear the driveshaft banging back and forth in the slack if I'm not careful. with the transmission in neutral and the parking brake on, i can turn the driveshaft about the same as the OP's video and the axles won't move(referenced where they enter the diff). The axles are dss level 5's and have no slack(stock axles can develop slack).
Jimmy, to answer your earlier question on the redline shockproof fluid, it made a little difference. It dampened the clunk but it is still there and annoying. I think i'm going to have to rebuild my diff at some point with a solid spacer. It sucks because I just had it out over the summer to resealed the diff and installed new axle seals. I'm such an idiot for forgetting to check the backlash.
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