perfect.ta

Ok it a H/C 98 trans am m6 . I have been geting a bad vibration felt at +80 miles speed in the consol next to the shifter I tried almost every thing . Replaced the drive shaft wich was bent .and still its there . Change the engine and transmition mounts . No help . Replaced the clutch still there . Instaled a new ring and pinion set . No help replaced the rear axles . Still vibrates . I also replaced the factory tourque arm with a tunel type BMR amd overhauled the t-56 and still no help . And whats funny after changing all of thos I still dameged the rear drive shaft and the transmission mount . . Car runs smooth till the speed of 80 miles . Then sound vibration comes . I also knotesed that when I had the factory tourqe arm the shaft use to rub on the bar . I even changed the 2 tires and inspected the rims . But still I cant find a solution can any one suggest some thing els

Daniel Richards

iTrader: (1)

rear shocks, if the air in my Monroe Max Air shocks get to low they feel like an unbalanced tire, you could also try a different shop to balance your tires, I had a shop I used for over a decade but lately (after there big expansion) I was getting plagued with vibrations so I went to a different shop recommended by one of my mechanics and when he put the tires on his balancer 2 wheels where perfect and the other 2 where so far off they actually got closer to being in balance with the weights removed.

JRENIGAR

iTrader: (37)

Have you tried road force balancing the tires? I had this done and it actually cured on of my phantom vibrations.

Midnight02

iTrader: (8)

Wow, that's an extensive list of items replaced to try to solve this problem. Given all of that, I experienced a similar issue and it was a tire. Had then balanced multiple times and everything checked out fine. Finally said "screw it" and replaced the tires and I haven't had the problem since.

Daniel Richards

iTrader: (1)

I did front wheel bearings, steering rack, tie rod ends and brakes trying to track down the one I had and come to find it was the balance of the tires because the old shop now sucks (see my previous post) I still have some but I put the remaining on the 200k mile factory front decarbon shocks.

Daniel Richards

iTrader: (1)

just found out my local Ford dealership has one of the Hunter RF balancers, may have to look into that sometime (to see if the guys are well trained on it).

perfect.ta

I dont think its the wheels cause I even tried swaping wheels from my other trans am f body as well wich I am sure I don't have any problem with . But still the vibration is there . Checked the balance on those wheels to they are ok . And today I checked the sway bar condition and its ok .. . The vibration also seems to be felt hard when I let go of the axcelerator

TA_Freak

I had the same issue but at a lower speed. I swapped my poly transmission mount with a rubber mount to correct the issue. What's the history on this? Has it been this way since you've owned the car?

lees02WS6

iTrader: (5)

You verified your driveline angles are correct? Pinion and tailshaft are at equal angles?

perfect.ta

I had this car for a long time . This happend after I street raced a swapped 2jz gt33 skyline and we started from roll second gear . All went fine till 5th gear I smoked him 2 . And I was running on street tiers with forged rims . Tier size was 295/35 . After slowing down and leaving the street race I notesed this vib . And yeah I remesured the pinion angle with the drive shaft . But I didn't have a magnetic gauge so what am gona do today is replace the transmission mount again and instal the claim shell factory tourqe bar insted of the bmr loop type tunel tourqe arm . Just to make sure I have a correct pinion angle

98cherrySS

iTrader: (2)

Did you replace the tail shaft bushing during the overhaul? I had a vibration at 80 directly below the console shifter. Swapped the tail shaft bushing and no more vibes.

trans_am7935

iTrader: (15)

This also solve my vibration above 70mph. It makes a world of difference, GM does this from the factory on all Corvettes, the ZL1 and Z28. Once you pass the 245 mark on a tire width, it is recommended by GM to do this as it is the best balance you can get. You have to ask the shop to do it though or they wont, even if they have the machine.

97FormulaWS-6

iTrader: (1)

What did you replace the driveshaft with? The LS1 F-body aluminum shafts have a natural frequency harmonic around that speed; might want to look into an upgraded shaft from Denny's or similar.

(The harmonics I was told by Denny when I bought my Nitrous Ready shaft from him. Shot the **** for probably an hour when I picked up my DS)