Opinions on Propshaft “Rubber” Couplings!
05-14-2012, 06:17 PM
#41
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05-15-2012, 09:53 AM
#42
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Jay back here with trans/torque tube work update.
TC had backed it self out of trans pump and ring gear ate into bell housing; ruining pump and bell housing due to bad couplings and bearings.
It was a 10mm torque tube and I found an 04 12mm TT w/10k miles on it for $400 (call them what you will; I call them junkyards). The old TT was obviously shot as you could physically pull & push the shaft a good inch through the tube...these things are a maintenance item with catastrophic results when they fail and they WILL fail. They turn @ engine RPM; use your imagination as to what they can do when they are allowed to fail...
TC had backed it self out of trans pump and ring gear ate into bell housing; ruining pump and bell housing due to bad couplings and bearings.
It was a 10mm torque tube and I found an 04 12mm TT w/10k miles on it for $400 (call them what you will; I call them junkyards). The old TT was obviously shot as you could physically pull & push the shaft a good inch through the tube...these things are a maintenance item with catastrophic results when they fail and they WILL fail. They turn @ engine RPM; use your imagination as to what they can do when they are allowed to fail...
05-15-2012, 10:45 AM
#43
Safety Car
My 2000 coupe A4 has part number 12561081
The later 200? A4 has part number 12564456
I have both sitting here. The late one is going in the car. I suppose I should have a look see inside.
Same as you have?
Ron
The later 200? A4 has part number 12564456
I have both sitting here. The late one is going in the car. I suppose I should have a look see inside.
Same as you have?
Ron
05-15-2012, 12:08 PM
#44
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do a visual inspectionJay
05-15-2012, 01:01 PM
#45
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Start A poll, With miles and years when torque tube went boom OR couplers needed changed. For your info a bmw 318i uses the same couplers, it has less then 150 hp. You want to argue, go for it. I've changed one tube and another set of couplers in 6 yrs, this is "Brillant".
If you don't like them then there is a company that will fabricate a u-joint based shaft for you. I just can't remember the company name. Or, install 2 solid couplers and shim for true and hope for the best...
My car was in the 110k mile range and the 10mm couplers still looked decent. Lots of highway miles I suspect before I bought it.
Last edited by lionelhutz; 05-15-2012 at 02:40 PM.
05-15-2012, 01:27 PM
#46
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The BMW has the coupler after the transmission. The first gear ratio of the different 318i trans are all over 3.7:1. A BMW producing say a peak torque of 110ft-lbs at the engine would put >400 ft-lbs of torque into the coupler in first gear. I think we know who's the real "Brillant [sic]" one is here considering how wrong your BMW HP arguement is...
If you don't like them then there is a company that will fabricate a u-joint based shaft for you. I just can't remember the company name. Or, install 2 solid couplers and shim for true and hope for the best...
My car was in the 110k mile range and the 10mm couplers still looked decent. Lots of highway miles I suspect before I bought it.
If you don't like them then there is a company that will fabricate a u-joint based shaft for you. I just can't remember the company name. Or, install 2 solid couplers and shim for true and hope for the best...
My car was in the 110k mile range and the 10mm couplers still looked decent. Lots of highway miles I suspect before I bought it.
Ck this out
05-15-2012, 02:44 PM
#47
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05-15-2012, 05:08 PM
#48
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Go find the right tool would be my advice, not too expensive, big truck part store should have them...them would be snap ring pliers about 16" long w/45 degree tips. I would estimate the ring is 3-4 inches in diameter X 3/16-1/8" holes...internal ring it is.
05-15-2012, 07:10 PM
#49
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Hey putz - your findings are cals. And yes it would be 400 in 1st gear. How many people drive in 1st all day putting that kind of load on their driveline for extended periods of time . You actual think a 4 cylinder that dynos out if lucky at 118 ft lbs of tq is going to put as much normal operating stress (peak power) on its driveline as a v8 engine - regardless of trans position. There is more to it then that.
05-15-2012, 07:40 PM
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So, now the name calling starts, lol. Torque is what twists the couplers. The HP number itself doesn't tell you anything about the stress the coupler is under.
Using your same logic, how many people drive around in their Vette under full throttle for extended periods of time?
Using your same logic, how many people drive around in their Vette under full throttle for extended periods of time?
05-15-2012, 07:43 PM
#51
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So, now the name calling starts, lol. Torque is what twists the couplers. The HP number itself doesn't tell you anything about the stress the coupler is under.
Using your same logic, how many people drive around in their Vette under full throttle for extended periods of time?
Using your same logic, how many people drive around in their Vette under full throttle for extended periods of time?
05-15-2012, 09:26 PM
#53
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O" you really explained that one. Wow - Wo . Enjoy fixing your couplers.
r2h - I was going to go with pfadt's CF shaft, but they only make it for 12mm not the 10. So drilling of the hubs had to be done. Not that big of deal, but for that kind of money, and little feedback. I decided to go with the craplers again. Depends how this current set lasts, I still might be going that route.
r2h - I was going to go with pfadt's CF shaft, but they only make it for 12mm not the 10. So drilling of the hubs had to be done. Not that big of deal, but for that kind of money, and little feedback. I decided to go with the craplers again. Depends how this current set lasts, I still might be going that route.
05-15-2012, 09:37 PM
#55
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The torque is the twisting force the engine produces and the force the couplers has to resist. HP is a calculated number that is proportional to torque x rpm and it's an indicator of how much work the torque can do. Keep the HP the same but change the rpm and the torque changes. Not very difficult to understand.
05-15-2012, 09:43 PM
#56
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I haven't read anything bad about it, but I doubt there is a large installed base of them. Haven't really read anything good either, just that a few people have installed them. Personally, it makes the shaft solid so installing solid couplers shimmed to make the whole shaft assembly true would likely give similar results. The difference would be that the stock AL shaft should turn into a "skipping rope" at a lower rpm compared to the carbon fiber item. You could have a heavier tube welded to your ends cheaper than the carbon fiber shaft to help avoid that. In the end, I haven't seen enough proof either way so pick your choice of "upgrades" and cross your fingers.
05-16-2012, 12:48 AM
#57
Team Owner
05-16-2012, 01:22 AM
#58
Safety Car
05-16-2012, 01:40 AM
#59
Team Owner
Personally, I'm a fan of the Six-Shooters. I've had them installed for over a year and so far so good. The only precautionary thing I would mention in regards to them would be to make sure your tunnel plate is an aftermarket (thicker) unit with the ceramic Jet-Hot type coating, or use a tunnel blanket heat shield. I have seem a picture of a partially melted Six-Shooter due to high exhaust temps directly below the tunnel/TT area. Protect the TT from high exhaust pipe temps and you're good; of course that has the added benefit of keeping cabin temps lower too.
05-16-2012, 08:43 AM
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The BMW has the coupler after the transmission. The first gear ratio of the different 318i trans are all over 3.7:1. A BMW producing say a peak torque of 110ft-lbs at the engine would put >400 ft-lbs of torque into the coupler in first gear. I think we know who the real "Brillant [sic]" one is here considering how wrong your BMW HP arguement is...
If you don't like them then there is a company that will fabricate a u-joint based shaft for you. I just can't remember the company name. Or, install 2 solid couplers and shim for true and hope for the best...
My car was in the 110k mile range and the 10mm couplers still looked decent. Lots of highway miles I suspect before I bought it.
If you don't like them then there is a company that will fabricate a u-joint based shaft for you. I just can't remember the company name. Or, install 2 solid couplers and shim for true and hope for the best...
My car was in the 110k mile range and the 10mm couplers still looked decent. Lots of highway miles I suspect before I bought it.
It would seen to me with the little engineering / physics 101 I've studied that in 1st gear the torque applied by the input shaft, i.e. TT assembly,is reduced then multiplied through through TC and transmission to the rear wheels. It would be in the highest gear that the most torque would be applied to couplers...and we drive up there a lot.
Also if you look at the application list for the subject BMW couplers they are used all the way up to their high output vehicles.
If there is a trick to these it is to be sure you have genuine BMW parts not Chinese or Mexican knock offs. Same w/the bearings we are going to use in the TT assembly.
Last point being; this assembly's longevity is too subjective to driving style, how hard the car shifts (incredible shock),and how often to predict in a general way how long before failure will occur. Any mods ya'll mention here are absolute trade offs up or down the line of your drivetrain.
What goes up...must come down. Purely a law of physics!
