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Dynotech Driveshaft Installation

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I would rate this installation at a 5 out of 10 for difficulty.
Tools needed:
1) 12mm 12point closed end wrench or socket with ratchet
2) 8mm hex (allen) wrench or ratchet bit with ball end 8mm hex
3) 10mm closed end wrench or socket with ratchet
4) 13mm socket with extension and ratchet
5) pry bar or large flat blade screwdriver
6) 4x ramps with built in wheel chocks (or equivilant)
7) angle finder (digital is preferred)
8) whatever tools are required to remove your exhaust (they vary with BOSS or GT stock and aftermarket exhaust systems)

STEP 1: elevate vehicle
you want to gain as much room as possible to work under the car safely. it is also important not to unload the rear suspension to accomplish this. i used a combination of 2 ramps and 2 cinder blocks. both are 7.5" high. the front should go up first, since a jack will not fit under the car up front with the rear already elevated. you can drive the front wheels up the ramps or jack it up (unloading the front suspension is not critical). set the chock to make sure the car will not roll off of your platform. now jack up the rear end from the rear axle pumkin. this prevents the rear suspension from unloading. place your platforms under the rear tires or place jack stands under each end of the axle tubes. set the rear of the car down on the platforms or jack stands. set the parking brake. if you used platforms under the rear tires, keep the jack under the pumpkin without pressure. you will need it later. your car should now look like this:

20130315152656.jpg


STEP 2: lower the exhaust
at a minimum, lower the front end of the exhaust and let it pivot down to gain somewhat obstructed access to the driveshaft. if you want clear access, remove the pipes between the cats and the over axle pipes. i chose to lower just the front. it was cumbersome, but worked.

20130315153312.jpg


STEP 3: remove the factory 2-piece driveshaft
i cant say what is the best order, but i chose to unbolt the the front, then the rear, then the center. any order you do it in, take care not to drop it when removing...there's even a sticker on the shaft that says "scrap if dropped"!

using the 12mm 12-point wrench, remove the 4 bolts securing the front of the driveshaft to the transmission flange. you will need to rotate the driveshaft 180 degrees to gain access to all the bolts. when you need to rotate, jack the pumpkin up off the platform to allow the wheels to turn. disengage the parking brake and place the transmission in neutral. rotate the driveshaft 180 degrees. reengage the parking brake and lower the pumpkin back onto the platform. mark the flange where one of the u-joint bearings sits in the yoke. for the best balance, you will want to match the position of the stock yoke with the dynotech yoke. it is a good practice to permanantly mark both the flanges and factory driveshaft, so that if you decide to return to stock someday, you can put the factory driveshaft back in the exact location.

20130315153303.jpg

20130315154535.jpg



using the 10mm wrench, remove the 6 bolts securing the rear of the driveshaft to the axle pinion flange. the driveshaft will have to be rotated the same as the front procedure to remove all 6 bolts. to save time, remove the 2 front bolts and the 3 rear bolts, then rotate the driveshaft and remove the last 2 front and 3 rear bolts.

20130315153954.jpg


using the 13mm socket, extension and ratchet, remove the 2 bolts securing the center bearing to the body.

20130315154008.jpg



using a pry bar or large flat blade screwdriver, pry the front joke from the flange and the cv from the pinion flange.

20130315154718.jpg



20130315155029.jpg


now carefully remove the driveshaft without letting the tube impact anything. with the exhaust removed, it can come straight down. with the front of the exhaust lowered, it must be lowered onto the exhaust and brought forward to be removed.

20130315155524.jpg


STEP 4: checking and setting angles
with a properly balanced driveshaft, vibrations come only from flange angles that are out of the tolerance of the driveshaft joints. the Dynotech driveshaft can operate with as much as 5 degrees of misalignment, but all double universal driveshafts will sacrifice longevity if the input and output are not parallel within 3 degrees. don't worry, this is not hard to accomplish.

first, you need to know what your angles are. place the angle finder on a flat surface of the transmission flange. record the angle. repeat for the axle pinion flange.

20130315162455.jpg


20130315162530.jpg


the trans should be angled down towards the rear. the pinion should be angled up towards the front or at zero. lets say the trans is at 3 degrees down and the pinion is at 3 degrees up. this makes the centerlines parallel to eachother. this is the perfect scenario for the driveshaft...except for the fact that under accelleration, the rear end twists up about 2 degrees(cw, if viewed from the driver side of the car). since the highest loads on the driveshaft are seen under accelleration, the ideal drivetrain angle places the centerlines in parallel then, not at rest. to accomplish this, we want to set our prevoiusly measured 3 degrees up on the pinion to 1 degree up. this will make our angle 3 degrees up under accelleration. for the info used above, this is what it should look like:

desiredpinionangle.jpg



if you have adjustable aftermarket trailing arms in the rear, make adjustments until you get the number you need. if you have stock trailing arms with no adjustment, you need to make a judgement call on additional parts. if your angles are within 3 degrees of optimum, you will be fine. if not, you really want to consider aftermarket upper or lower arms with adjustability to get your angles within tolerance.

STEP 5: installing the Dynotech driveshaft
using the 8mm hex wrench, the 2 sheer bolts must be installed in the pinion flange with locktite and torqued to 25ft/lbs. they are to be located 180 degrees from eachother. for the easiest access, place them horizontal as shown.

20130315160425.jpg


compress the driveshaft before bringing it under the car. the slip joint is VERY tight and is difficult to do under the vehicle. carefully bring the driveshaft into the transmission tunnel (do not allow the tube to impact anything) and attach the billet aluminum yoke to the pinion flange wit hteh 2 blind holes engaging with the 2 previously installed sheer bolts. install the 4 bolts with the 8mm hex wrench. a ball end wrench may be required. a ball end bit with a ratchet is the best way. tighten the 4 bolts to 25ft/lbs. the driveshaft rotating procedure from STEP 3 will have to be implemented to get all 4 bolts tightened. next, bring the front of the driveshaft up to the transmission flange. the driveshaft may need to be further comressed or extended to get it to seat on the flange landing. get it to fully seat on the flange and rotate the transmission flange until the mark made in STEP 3 lines up with the u-joint bearing in the yoke (the same position as the original driveshaft). install the original 4 bolts with locktite and torque to the manufacturer's specs (i don't know what this is...i tighten until i grunt). again, the driveshaft needs to be rotated to gain access to all 4 bolts.

DOUBLE CHECK ALL 8 BOLTS ARE TORQUED PROPERLY!!

STEP 6: button it up and drop it down
reverse your exhaust disassembly procedure. before tightening everything back up, make sure your mufflers didn't shift (mine did and rattled until i figured out they shifted back and hit my trailer hitch crossbar). bring the car back down to terra firma.

STEP 7: test drive
you know the drill. do your thing. you will immediately notice less clunking and a more direct link feeling. you will also notice livlier accelleration from a stop. if you already had an adjustable upper arm, the noise level has not changed much. if you installed one with the driveshaft, you will notice gear noise. don't panic...its normal and due to the tighter bushings (or sherical bearings) in the armarm, not the driveshaft. you may experience vibrations you didn't remember before. don't worry...they were there all along. you just weren't concentrating on them before. if the driveshaft was having an issue with balance or engle misalignment, it would rattle the fillings out of your teeth.

i have one issue that drives me nuts. when coasting in a state of equilibrium (engine isn't slowing down or accellerating the car), there is a terrible rattling noise. i found out that the rear gears have way too much backlash and the driveshaft is allowed around 5-10 degrees of rotation without moving the wheels. this slop is causing my rattling. with the stock driveshaft, it had so much slop in itself, that i guess it all acted as an isolator from the gear slop? i am going to have it corrected asap. i wanted to include this info in case someone else experienced this rattling after a 1-piece install.
 
Nice writeup! I don't know how critical this is, but I would maybe mark the location of the original driveshaft flanges, in case you need/want to replace the OEM driveshaft in the future, it will be all nice and balanced like it came from the factory.

Again, not sure if it matters, but it something I have always done on my quattros.
 

Justin

Save the dawn for your dishes!!!
I did the install with the axle in full droop. I used the parking brake to keep the shaft from spinning while I removed the bolts then released it to turn it a little more to get to the next one then pulled the ebrake again.
 

TMSBOSS

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Justin said:
I did the install with the axle in full droop. I used the parking brake to keep the shaft from spinning while I removed the bolts then released it to turn it a little more to get to the next one then pulled the ebrake again.

Same here.

I placed jack stands under the body at jack points. This allowed the rear axle to hang at full extension. The shaft then came out without dropping the exhaust. A little tight going back in. No worries with the exhaust, it stayed connected.
 

Justin

Save the dawn for your dishes!!!
pufferfish said:
you missed the point of not unloading the rear suspension ???
no I get it was for checking pinion angle. Just saying its easier to remove and install with the axle in droop. I didnt even check the angle when I installed mine as the car isnt lowered. I check the pinion angle to the driveshaft angle after I installed the steeda adjustable UCA and Bracket. mine is dailed in right at a -2. I checked it with the car on ramps in the rear only.


The more you get away from having all solid mounting points the more the rearend is going to try and rotate upward during launch. Therefore the more angle you must start with to prevent the angle from becoming positive (+). The idea is that when the rearend rotates you want the angle between the driveshaft and the pinion would be 0.

Long story short there is more than one way to skin a cat
 

pufferfish

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Justin said:
no I get it was for checking pinion angle. Just saying its easier to remove and install with the axle in droop. I didnt even check the angle when I installed mine as the car isnt lowered. I check the pinion angle to the driveshaft angle after I installed the steeda adjustable UCA and Bracket. mine is dailed in right at a -2. I checked it with the car on ramps in the rear only.

Long story short there is more than one way to skin a cat

^THIS^ is what people need to know when they are looking at instructions. you did have to go back up with a loaded suspension to check your angles. i agree, there are other ways to do it, but unless you are clear on your procedure to get from A to B, those looking for answers just assume they can swap one step for another.
 

Justin

Save the dawn for your dishes!!!
My thought is if you are at stock ride height I dont see a need to check pinion angle. It should be good to go. Now if you lower your car you should check it after you lower it one piece driveshaft or not.
 

TMSBOSS

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pufferfish said:
you missed the point of not unloading the rear suspension ???

Not at all.

The suspension only has to be loaded when checking the angle and gap.

You do not need it in the way when removing and installing the shaft.

The exhaust can stay in place and the angle measured. Just jack up the axle.

I prefer not disconnecting exhaust when not needed. That's the point.
 

pufferfish

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just an update for how it works. i was at the track this weekend and topped out my 160 speedo (its a GT) and zero vibration. all fillings still in tact! the gear backlash is another story. that will need to be fixed before the next track event. that point between accelleration and decelleration sounded like a giant meat grinder!

that was the top of 5th (1:1), so about 7400rpm on the driveshaft.

so, with simple hand tools and and proper technique, these shafts are ready for some serious speed!
 

steveespo

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pufferfish said:
just an update for how it works. i was at the track this weekend and topped out my 160 speedo (its a GT) and zero vibration. all fillings still in tact! the gear backlash is another story. that will need to be fixed before the next track event. that point between accelleration and decelleration sounded like a giant meat grinder!

that was the top of 5th (1:1), so about 7400rpm on the driveshaft.

so, with simple hand tools and and proper technique, these shafts are ready for some serious speed!
Where did you run this weekend? 160 is going pretty fast on any of the road courses I know.
Steve
 

pufferfish

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at VIR back straight, but i dont think i actually got to 160, just the speedo read that. my new race tires are smaller than my street tires, so the speedo was off. it was probably more like 155. that said, if i had more confidence i could whoah her down at the end, i could have shifted into 6th and gained more speed. my exit speed at oaktree is so much faster with the hoosiers and i have the grip to acellerate sooner. and i am certain that driveshaft gaind me a couple of mph too. i breathed off throttle before i crested the hill.
 
Finally got my Dynotech DS installed. Went in with no issues. It's a super high quality piece, and my initial road test on the interstate yielded no vibrations or anything unusual. Runs smooth as silk.

The instructions provided in this thread were very helpful. I found, however, that my stock DS came out and the Dynotech went in without either loosening the exhaust or letting the rear axle hang. Getting the old one out was a bit tight, but working gingerly and a letting loose few well timed swear words helped it slide right out the back.

Also installed a Stiffler DS safety loop while I was under the car had everything apart. It's a high quality heavy duty safety loop... fairly easy to install, although you have to remove the 3 trans mount bolts (and support the trans with a jack) to install it. Not hard and it looks like it belongs there.
 
Installed mine after UPS finally managed to find and deliver it. Tested to 145 MPH and it is smooth as silk. Many thanks to Pufferfish for setting this up.
 

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