Driveline vibration. HELP! (long)
Thread Starter
TECH Apprentice
Joined: Nov 2001
Posts: 387
Likes: 0
From: Casselberry, FL.
Driveline vibration. HELP! (long) I have a driveline vibration that is driving me insane. Let's start from the beginning. I have a 99 TA A4. For almost two years I ran a SY3500 with no problems. In November I installed a Thunder 224 cam and LS6 intake. With these new mods I felt that I needed a bigger harder hitting converter so I bought a TP4400. I installed the converter and immediatly noticed a driveline "shutter" at around 40-44 mph. I first thought that there was a problem with the converter so I called Mike and he suggested that I put a stock MAF on the car. I did and it did nothing to correct the problem. He also suggested that the torque arm might not be at the right angle. I had the angle checked and it was about 3 degrees off. In the mean time I switched over to a PI3200 due to driving the car for sales everyday. I then ordered the BMR adjustable torque arm. I installed the arm and had Mike Norris adjust it for me to -2. The shutter is still there. <img src="gr_images/icons/mad.gif" border="0"> I have had a 4-wheel alignment done, a wheel balancing, and I have tried a different driveshaft all with the same results. Shutter. <img src="gr_sad.gif" border="0">
This problem occurs when I let off the gas and the car is coasting at around 40-44mph. It feels as though something is tugging against the car. The car runs awsome and I hear no noise what so ever. I didn't think it was a problem with the tranny because it is more speed related than RPM related.
Anybody have any suggestions. Please...
Jim
<img src="images/icons/confused.gif" border="0"> <img src="gr_images/icons/mad.gif" border="0"> <img src="gr_sad.gif" border="0"> <img src="graemlins/gr_cry.gif" border="0" alt="[whiner]" /> <img src="graemlins/gr_barf.gif" border="0" alt="[barf]" />
This problem occurs when I let off the gas and the car is coasting at around 40-44mph. It feels as though something is tugging against the car. The car runs awsome and I hear no noise what so ever. I didn't think it was a problem with the tranny because it is more speed related than RPM related.
Anybody have any suggestions. Please...
Jim
<img src="images/icons/confused.gif" border="0"> <img src="gr_images/icons/mad.gif" border="0"> <img src="gr_sad.gif" border="0"> <img src="graemlins/gr_cry.gif" border="0" alt="[whiner]" /> <img src="graemlins/gr_barf.gif" border="0" alt="[barf]" />
TECH Addict
Joined: Jan 2002
Posts: 2,950
Likes: 0
From: Magee MS
Re: Driveline vibration. HELP! (long) I am not sure what your problem could be but I have something of the same kind of problem..... When I go down the road I feel a vibration that seems to be comming from the tranny mount.... I looked at the mount and it seemed to be ok..... Im thinking that it could be the torque arm..... I'm going to order a new mount from Thunder Racing ,when I find my credit card, and put it on at school(im takin auto mechanics and we have a rack) and maybe try to tighten some of the bolts..... if this doesn't stop that problem I dont know what I'm going to do..... I am also going to change my U-joints... I think I might have discovered a new vibration this morning which feels like a tire...... I guess thats what I get for letting the car sit for 6 months without a transmission(you may slap me now)
Josh S.
Josh S.
"All Motor 9 Second club member"
iTrader: (60)
Joined: Nov 2001
Posts: 3,235
Likes: 2
From: On the Bumper!
Re: Driveline vibration. HELP! (long) I would have to say it's the adjustment of the Torque arm.I had mine set wrong when I first installed the TA and it did exactly like you describe. There has been quite a bit of question over the proper way to adjust.If the DS is +3 (that is 3 deg. front of the shaft pointing UP), the you need to subtract 2 degress from that and that is what your differential angle should be, which is +1. If you line them up in a straight line this will tell you if that is what's causing the vibration, but it won't help your traction until you bring the pinion angle down 2 degrees. Also , if you have a poly trans mount it will magnify any and all vibrations that you didn't know existed.It will rattle your teeth out.It's the price we pay for performance, Good luck.
