Vibration Problem, possible cause Pinion?
Ok alignment in the horizontal plane has been done and is spot on, and let me tell you the vibration has gone down a lot it's like driving a different car the mirrors are still where as before because of more vibration you could only see a blur when looking at the mirrors, although the vibration has decreased it is still there, I haven't measured runout at the rear of the driveshaft after the Horizontal alignment I will do that soon to see if there is change, I have one question for the people that own torque arm relocation cross members because approaching 110 mph I can feel vibration not terrible but noticeable, my question to the people that own torque arm relocation brackets, do you experience vibration at 110mph+ speeds I thought that maybe because the torque arm is now connected to the cross member that it is transmitting these vibes, your input would greatly be appreciated please let me know what speeds you have been to and what it feels like.
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Ok latest update after I fixed the horizontal alignment of the pinion as I have said vibes significantly went down and I just checked the runout numbers at the rear of the driveshaft close to the pinion runout has gone from 0.040 thous to 0.012 thous so I knew that the left over vibration is not from the driveshaft or pinion, I checked runout of the left axle shaft and came up with no more then 0.020 now the right one on the other hand has got 0.100 checked only horizontaly not even vertically I ran it in first gear with the rear jacked up I could visibly see the the right wheel and rim move around, the wheels and rims are not at fault because I had the front set swapped out with the rear, two years of chasing this vibe went through two expensive driveshafts, many sleepless nights all because of a bent axle after I bought a used differential, I wish I could go back in time and tell myself STOP! It's the right axle, what a coincidence though Darthv8r me and you both got to the source of the issue around the same town and we both have Trans Am!
Want another coincidence? My right axle tube is bent up at a 2 degree angle, but my left is level. In an earlier post I had asked if this could cause vibration, but nobody answered. I guess you just did. Right side axle to boot.
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hahahaha that's crazy, Yes life can work in mysterious ways I don't think it's a coincedence though that our paths crossed, your previous post actually gave me the idea that since I have solved the shaft runout then it's must something to do with the wheel assembly.
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Ok it turned out not to be a bad axle shaft and since nobody gave me an answer on if they are feeling vibes with torque arm relocation kits even at perfect pinion angles, I have tested it myself I set up the absolutely best pinion angle there is to set up and thrust alignment was spot on, with the rear on jack stands I got a freind to get it to the RPM where I felt vibes went underneath and the driveshaft was spinning absolutely beatifuly no wobble no whipping nothing, I then put my hand on the torque arm and guess what? I felt vibes and those vibes well go into the cabin because the torque arm is sitting on the crossmember so it doesn't matter what pinion angle you use or what driveshaft you use if your torque arm is not sitting on the transmission you will get vibes in your cabin if you say aren't getting them then you are just lying to yourself and will put people on a wild chase, point of the matter: If you are going to use a torque arm relocation bracket no matter what brand you use or how you set it up you will GET VIBES past through in to your cabin by the torque arm mounted on the crossmember for the people that own M6 cars this well be felt at the end of the 3 gear rpm range, end of fourth gear rpm range, 5th gear past 3000 rpm and 6th Gear 2000 rpm and don't be fooled by the major companies claiming a vibration free ride because of total pinion angle adjustablity control because that is just total bull, trust me take it from someone that has been through 2 good driveshafts, a million pinion angles, a BMR short torque arm kit, a custom made torque arm relocation crossmember and through many hours of trial and error.
