nseoi

I know this has been posted a few times and people give a few different possibilities but i just wanted to narrow it down.

when i go 80mph+ (the faster the worse it gets, like 100+mph is crazy) the car starts to shake. some people have said that it could as simple as an unbalanced wheel but it seems WAY too strong for that. the other thing i noticed is that what shakes the worst is the shifter handle, like if the whole drivetrain is causing this. it occurs just as bad in gear or in neutral so i think that will eliminate the engine and the engine mounts (both the engine and engine mounts are new anyway).
so can i just go to a mechanic and ask him to look at my driveshaft and u joints for problems?

mjr46

sure do what you feel necessary.... but have the wheels spin balanced to check for any irregularities in the tire and or rim. on a spin balancer you can also check rim run out at least on mine you can. I'd have the tires balanced to the nearest gram...most balance is ounces in a round off mode but you can set the balancer up to grams usually and eliminate the round off mode which will tell you exactlly where the wheels are at

nseoi

ah nice tip with the grams, ill keep that in mind since im getting new tires soon too

mattdel

good luck finding someone with a gram balancer. i've only heard of them. never once seen one in person. they just aren't in high demand, and really, balancing that close isn't necessary unless you are over 120mph alot.
your wheels/tires may be out of balance, regardless, but it shouldn't take a gram balancer to fix them.

mjr46

Trust me when you work on a lot of BMW'S and mercedes benz Owners of those cars are quite finicky..the slightest vibration at any speed and they want it gone......I've had to balance many tires on those types of cars that way to remove the most minute of vibrations and do it in a non-round off mode. But then again those types of cars are luxury cars whose ride quiality is much more sensitive then that of a mustang . Most digital balancers have the grams option mine is fairly new and I can select from grams to ounces. true you shouldn't have to balance in grams to fix a big vibration problem just allows better ride quality through a broader mph range

hayden

mine is almost the same way... if im going 80+ and let off the gas mine kinda vibrates not really a shake though, but as long as i keep my foot on the gas it doesnt do it, only when i let off

nseoi

ok got back from the mechanic, my Ujoint is near ready to blow up. i just picked up a new ford racing aluminum driveshaft with all the goodies and will put it on tomorrow, let you guys know how it goes then

nseoi

ok i calculated my budget and cant afford the $40 to put it on before friday.
I have replaced a driveshaft before but never a new one.
questions:
do i have to add any grease to the ujoints or anything? i was told i need locktight for the driveshaft bolts, is this true?
and is there anyway to prevent the transmission for spewing all the fluid when i take out the yolk?
thanks

mjr46

if you jack the back up and place stands underneath it'll tilt all the fluid forward........then you'll needa 12mm 12 point wrench to remove the bolts and use blue loctite to put them back in ...it shouldnt take you more then 15 20 minutes to do the whole job....make sure the trans output shaft seal isn't leaking if so nows the time to replace it.....good luck I don't think the ford racing driveshaft has greasable joints I think they are sealed...I could be wrong but if they are non-greaseable then just assemble and go.

nseoi

cool, hopefully all goes well tonight, will be working with a flashlight