i just got my 88 iroc back on the road last month, with a new motor and all. everything seems good but today i ran it up to around 130 and i thought it was going to fall apart it started around 100 and got worse any ideas, it feels like it it in the drive line. it has a new 700 trans alu drive shaft new u joints the rear has not been touched yet it is a b/w with 120,000 on it. o yeah and its got 4 brand new tires on it thas are balanced on a computer balancer. thanks

ben

 

Well i assume it didnt shake before all the new stuff?
Is'nt 130 speeding?
Joking aside if it was ok before, and its a new motor, obviously the converter bolts are tight, and all the bellhousing bolts, to engine block are tight. Same goes for the gearbox and engine mountings.
You could try turning the proshaft around 180 degrees, that can help plenty if its body shake, just to see if its better or worse.
Definately check the u-joints are tight, i dont think wheel balance is an issue as you cant drive through the vibes, as they get worse it seems.
If it was loose wheel nuts you would feel it long before.
As i said earlier if the car was fine before all the mods, it has to be something thats been added.

 

what do you meen turing the shaft 180, taking it out of the trans and turning it, or at the u joint????

 

unbolt your drive-shaft from the rear end and spin it 180 degrees and reatach the drive -shaft.

later and

GB

rick

 

ok cool ill try that. has any one had a problem like this with one of these 1LE shafts