My question is why do they put a 2 piece drive shaft in a car like this in the 1st place and do the Hell Cats come this way too ?
I don’t think the issue is due to the 2-piece driveshaft itself, although it is directly related since it requires the center bearing which is the source of failure. As mentioned prior the issue seems to be specific to a certain year or range of years, with many older challengers not showing this failure.My question is why do they put a 2 piece drive shaft in a car like this in the 1st place and do the Hell Cats come this way too ?
and you say your retired !! ha haGot to look over the new 4" Aluminum driveshaft today the welds are excellent very pleased with the DSS quality work, did a mock up next to the old OEM 2 piece driveshaft, not sure what the 2 piece actually weighs but the single piece seems a little lighter but not much. From the beginning it is advertised as 4", but seeing it in reality, is definitely understanding the size difference.
Took Black Beauty out for a ride today and got a check engine light of a failed O2 sensor, I knew when I had put the headers and high flow cats I should have changed those sensors then, but hind sight as they say is 20/20 since I will be dropping the entire exhaust, I ordered the 4 O2 sensors to do it all at one time.
My next week to do list, Lord Willing:
Change engine oil and filter.
Change out Differential oil.
Drop the Exhaust for driveshaft swap and replace the O2 sensors.
Replace the flange bolts on the BBK header to Cats, the ones supplied by BBK have never worked right.
Remove the OEM driveshaft and install the new 4" Aluminum driveshaft from the Driveshaft Shop.
Remove and replace the OEM TPMS pickup module located behind the inner fender liner passenger rear side.
Hopefully that is all? Ry
The hardest part with the ramps is torquing down the new bolts.On ramps it’s a super tight fit under the car, I was struggling to reach the screws so if you have access to a lift definitely go that route. As you can see, this is the OEM hardware. Question came up regarding ARP 12 point bolt upgrade, after dealing with these I can confidently say it’ll be worth the price just in saving aggravation alone.
This was quoted from the Driveshaft Shops thread post from the Camaro forums:> 2pc vs. 1pc driveshaft - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums - Camaro5.comlong but good
This is a question we get allot, this is our take on the subject. to start driveshaft technology has come a long way since the 1st gen Camaro's. although thru the years Gm has always used a single shaft with 2 U-joints (although there was a odd 6cly shaft on the last generation cars that had a 2 piece and a CV but it was a disaster) they used them until the last generation of cars. In the past a 2 piece shaft was used when the overall length of the tube was too long and would hit critical speed (the speed where the tube goes into a jump rope affect and will break) jump forward to the "Modern Muscle cars" and all of them have 2 piece shafts. Yes the Mustang-Chryslers and the Chevy cars of today all have a 2 piece shafts, but not all have it for the same reason. The Mustang has a very heavy shaft that had a 9lb Harmonic damper in the back shaft (the entire shaft is about 49lbs) its used to calm the harmonic vibrations of the motor. You can put a single shaft in there cars but there are a handful out there that have such bad harmonics that it needs that heavy shaft to calm the problem. The Chrysler is a different story, the chassis is made by Mercedes (its a E class car underneath) and has the problem with length so a single shaft would not be able to be used. Both the Chrysler and the Chevy use a rubber drive called a Guibo joint (believe it or not that is the correct term) these joints are designed for torsional dampening (not vibration) or in other words when you put the car into gear it takes the slap out of the drive train and will give the car a smother transition of power, its great in a luxury car but in our opinion it has no place in the performance world. now the real reason we believe the 2 piece shafts are being used on the new cars is harmonic and vibration dampening. All of the new cars coming out are uni-body and built so tight that the smallest amount of harmonics from the Engine/Drive train will find its way into the drivers cabin. Think about when you started changing the suspension parts to polyurethane and felt the cars rough edges more, think back to the old days when a solid motor mount was used and how it would be felt thru the entire car (keep in mind the older cars had frames that were isolated from the body with rubber mounts) so keeping this Harmonic monster under control is a big job and the driveshaft being a hollow tube acts like a speaker or broadcaster of the harmonics in the system. so jump forward to the question, it all depends on the car and what its being used for. a 2 piece shaft will have
a greater critical speed but at the cost of weight (and the hanger jumping up and down) the single shaft will be more responsive to throttle input and be lighter so in a drag car or a fast street car there would be advantages.
The critical speed of the single shaft will depend on quite a few things. The drive train manual covers many of these including
material density,material type,modulus of elasticity. The other factors that come into play are mounting points, are they moving or or rigid. The rear gear, tire diameter also will have an Effect. i know im getting real technical but there has been some bad info floating around some other forums' and i thought you guys might want to know the real deal. On top of all this you have mounting of the shaft, this believe it or not will also affect the outcome and its why we use the Billet plates and not a traditional yoke, since we have taken delivery of the high speed balancer we have come to realize just how "off" a pinion yoke can be. When we 1st received the machine we had to make our own balancing fixtures and went right ahead and used some billet yokes. I will not tell you the name of the manufacturer but we tried more than one but always had the same result, if the part was taken off and put back on it didn't center itself the same. We have been doing some testing for some of the bigger NASCAR teams being were here in the Charlotte area and after checking them we were surprised to find they have a tool that sits into the pinion yoke to check run out (a funky ball looking thing), some pass and allot don't make it, in fact they match the shafts run out to the pinion yoke run out. After realizing the yokes would not work on the balancer we decided to use billet plates with flanges. It was a perfect match every time. The Camaro had the rubber drives (Guibo joints) from the factory and the one real nice thing about them is there is a pin in the middle, this pin is a precision 16mm part that is ground on center with all the internal bearing journals of the trans and diff shafts.
To put it clearly its a perfect point to pick up a center line so we make the plate to pick up the center line for both the CV mount and the flange mounts. This along with either of the shaft will produce a vibration free shaft, so if high speed is what your after (were talking over 200mph) the 2 piece could have one draw back but we have addresses it, the fact that anything with a slider will become unstable after 5000rpm (due to the play needed to slide). we have installed a set screw on the 2 piece system to be tightened after install to stop this instability. As for the single shaft we are using a high speed CV that has virtually no play and it is about the most stable thing we see in the balancer at high speed (right up to 9500rpm). Our single aluminum shaft is rated for about 200mph with a 3:54 rear gear, the higher the numeric number the lower the mph (a 3:73 gear will change it by about 400rpm so its a little lower) of coarse a carbon fiber shaft will spin about 25% higher (using a .89 safe factor) so there you have it, hope i didn't go to far.....
very informative post, specifically the excerpt from the Camaro forum - thanks for sharing!A Modern Day Driveshaft Education:
Why would anyone swap out an OEM design for an aftermarket design?
I had my concerns going with a single driveshaft over the 2 piece design so I tried to find reasons why Dodge used it in the Challenger and the Charger, but also Chrysler uses it in the Chrysler 300, etc. I was kinda shocked to learn it is also used in the Chevrolet Camaro, and the Ford Mustang, OK, Why?
Reasons, Not necessarily in order, Manufacturing cost (Mostly in the balancing of the mass produced OEM domestic driveshafts, which are balanced in the 3,000 to 4,000 rpm range.), Transmission to Differential alignment issues, Safer at high speeds regarding vibration and reaching critical speed problems, The ability to use smaller shaft diameters for shaft tunnel fitting convenience. Now not an official reason but it being used as a fuse, so it would fail before other more critical elements did, and it is cheaper to replace for the corporations to be liable for, much, much, cheaper to replace a driveshaft over a transmission or differential.
So as a cautious warning anyone with a new still well within factory warranty car, going to a single driveshaft with high horsepower capability probably will be all the excuse they need to completely void your warranty!
#1 Clearance, would it significantly clear the stock hanger center bearing mounts already factory installed in the driveshaft tunnel? Yes it clears those, no problem.
Would it clear the exhaust or would I have to modify it? My Magnaflow clears, no problem.
#2 Driveshaft diameter, why so large, the 4" Aluminum driveshaft is quite huge for a driveshaft diameter? I learned two new to me words, whipping effect, that is the critical speed at which the driveshaft can whip like a rope causing major failure. The larger the tube diameter the higher the critical speed whip out point and the Driveshaft Shop balances their dirveshafts at 9,500rpm. On the old traditional driveshafts the driveshaft was splined to fit the transmission output shaft, so there was in and out movement as the rear differential moved up and down with leaf springs. But at high critical speed if the whipping effect happens to the shaft, it can pull completely free from the transmission and that is a disaster if it falls down to the pavement. Thus the requirement of safety loops at the drag strip, to catch the driveshaft in just such a failure.
Now our Challengers are quite unique, in that we have a rear cradle that the differential is bolted to and remains static, the independent suspension of just the wheels moving up and down, changes the need for a splined driveshaft. So by going to a 4" diameter driveshaft seriously decreasing the point of critical whip out, CV joints can now be used on the driveshaft making the ride smoother and vibration free. I have no idea what the top speed capability of the single piece driveshaft actually is, some said 200mph, but I have zero intentions of sustained speeds over 100mph in my car period, so the failure point is irrelevant to me anyway.
#3 Performance, obviously there is no horsepower increase as it does not change what the engine was outputting before the swap, but there is less drive line resistance as it eliminates the center support bearing and a CV joint, so your rear end torque does increase. That shows up with easier rear tire spin and even less gas to get it happening, so there's that.
Where am I getting some of this information? Quote posted from 1/27/2011 and please keep in mind the Driveshaft Shop has made many design improvements since 2011.
This was quoted from the Driveshaft Shops thread post from the Camaro forums:> 2pc vs. 1pc driveshaft - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums - Camaro5.com