S60 vibration at speed?
Didn't you have to modify the driveshaft once you installed the S60? Just thinking that if your pinion angle was off when you measured for driveshaft length then your driveshaft may be a contributing factor as well.
TECH Apprentice
Joined: Oct 2018
Posts: 336
Likes: 85
From: Glendale, AZ
Driveline can be changed by the yoke positions relative to each other. Does the S60 have a longer snout, I honestly dont know? Swapping to a shorter or longer transmission. Both can change the angles.
I just went through this on my lifted truck, shook like I was driving a paint shaker. Lifted it and changed to a 14b rear. Short wheelbase k5. Ended up having a cv joint at the t-case because of the angles involved, even with the angles matching they were just too acute with a typical u joint.
CV swap, it works... however the pinion angle would most likely need to come up substantially as once you have a cv joint in there, there's nothing to cancel out the vibrations on the pinion ujoint at all. So having the pinion at 0 deg would be important.
I just went through this on my lifted truck, shook like I was driving a paint shaker. Lifted it and changed to a 14b rear. Short wheelbase k5. Ended up having a cv joint at the t-case because of the angles involved, even with the angles matching they were just too acute with a typical u joint.
CV swap, it works... however the pinion angle would most likely need to come up substantially as once you have a cv joint in there, there's nothing to cancel out the vibrations on the pinion ujoint at all. So having the pinion at 0 deg would be important.
11 Second Club
Joined: Jan 2003
Posts: 1,000
Likes: 134
The S60 is longer than the 10 bolt. Putting a CV joint in a 4th gen is ridiculous. There's hundreds of S60's out there in 4th gens with a one piece driveshaft without any vibration. `The people with vibrations need to put their car on a 4 post lift with car on it's wheels in the driving position and get the the rear pinion pointing down several degrees relative to the chassis of the car. That's how mine is and it's perfect no vibes.
Jeff99 do you have the stock torque arm or an adjustable one? Im using the stock torque arm. Im using stock length tubular lower control arms, which my only adjustment is switching holes on the lca brackets to correct angles and I have an adjustable panhard bar to center the rear. Im thinking either the driveshaft is out of balance or maybe the ujoint isn't happy when I bolted it up. I don't want to bring the car upto those speeds and wreak havoc on the pinion etc.
I had no troubles cruising 120mph+ and roll racing with the stock 10bolt prior to install. Im sure id be on a tow truck home if I try that now.
I had no troubles cruising 120mph+ and roll racing with the stock 10bolt prior to install. Im sure id be on a tow truck home if I try that now.
Last edited by Jeff99; Jun 28, 2019 at 07:48 AM.
Thread Starter
Joined: Nov 2010
Posts: 808
Likes: 62
From: Toronto Ontario Canada
I got the complete rearend and driveshaft from mwc. The rearend swap is meant to be a direct bolt in using factory tq arm and lower control arms etc without issue. My driveshaft is 1pc chromoly with hd yoke and u-joints and pinion. When I first put the rear in,i had set it all back to factory ride height and set the lca's and panhard to stock length during initial break-in which would not have presented the vibration at lower speeds.
I did find the problem as I just put the car up on stands with the suspension loaded. rotated the driveshaft and spotted the tailend on the u-joint 1 side was not seated correctly. I removed the driveshaft,rotated it 180* and then slowly tightened it down making sure the joint fully mated. At the same time I installed my new trackbar and panhard bar relocation brackets, double checked everything was as good as can be and headed to the highway. I crept up to higher speeds and had a slight vibration much higher in the 125mph range. Much more tolerable. I know the angle isn't going to be perfect until an adjustable tq arm is put on but Now I know it wasn't a bad driveshaft or joints.
As I was doing a cool down,I ran into some friends and decided to play..hitting boost cut on a hot humid night in a turbocar royally sucks,Im loving the gearing in the s60 with 3:55. So now the next step is an adjustable torque arm to fully dial in the angles. And tone down my wastgate spring as its too high on the street.
I did find the problem as I just put the car up on stands with the suspension loaded. rotated the driveshaft and spotted the tailend on the u-joint 1 side was not seated correctly. I removed the driveshaft,rotated it 180* and then slowly tightened it down making sure the joint fully mated. At the same time I installed my new trackbar and panhard bar relocation brackets, double checked everything was as good as can be and headed to the highway. I crept up to higher speeds and had a slight vibration much higher in the 125mph range. Much more tolerable. I know the angle isn't going to be perfect until an adjustable tq arm is put on but Now I know it wasn't a bad driveshaft or joints.
As I was doing a cool down,I ran into some friends and decided to play..hitting boost cut on a hot humid night in a turbocar royally sucks,Im loving the gearing in the s60 with 3:55. So now the next step is an adjustable torque arm to fully dial in the angles. And tone down my wastgate spring as its too high on the street.
