Rebalance old driveshaft or get an aluminum

[FrdMustangCpe]

ive had this driveshaft vibrating for about 2 months now and im either going to rebalance the old one or get an alum off of ebay

Rebalance: $55-$75 And still uses the stock d/s
Aluminum: Off of ebay $110-$150 New but more money

Would rebalancing a old d/s be worth it or would it go outta balance and possibly have the u-joints go out. Right now the u-joints are good, but still 17 years old. Should i just suck it up and get an alum .

The vibration is after 2500 seems to be in any gear but first. Has caused the h-pipe to muffler bolts to back out, almost costing me to loose my mufflers on the road. The lame mechanic the swapped my t-5 awhile back drove it today and said he thinks its the tranny, but this guy is lame. i brought it in there and told him there was a vibration after 2500 rpm. this clown puts the car in the air, calls me and tells me the d/s looks good...w/o driving it at all. its not gonna vibrate while its sittin there.

So pretty much i need to know if rebalancing the old one would be a waste or time/money

thanx
-Mike

 

[TheDevil]

Get the aluminum DS, if your gonna pay to ballance your old driveshaft pay a little more and get a better FMS aluminum unit with nice new u joints and ballanced to 6000 RPM.

 

[colemanitis]

Another vote for new aluminum. My stock driveshaft had a horrible vibration until I replaced it with a FMS aluminum driveshaft.

 

[battyice]

When did this vibration start? Was it after a transmission or rear gear swap? If that is the case, most likely you can "index" your driveshaft differently and reduce the vibration.

When your car was originally assembled, the drivetrain was balanced as a unit: the pinion, yoke, and driveshaft were all balanced together. Changing any of these components will throw off the factory balance.

You would be suprized at how much driveshaft vibration can be eliminated simply by unbolting the rear yoke, spinning the driveshaft 60 degrees, and rebolting it for a test drive. You may have to do this several times to find the best combination, but the difference should be noticeable.

If your car has been driving perfectly and all of a sudden got a vibration, disregard the steps above; they only apply if the vibration began after the driveshaft was reinstalled due to a gear/tranny swap. It is possible your driveshaft threw a weight and is now severely out of balance.

 

[FrdMustangCpe]

When did this vibration start?

well i hate to say i dont really know...when i first bought the car, i was just learning how to drive a stick, i wasnt really running it at all. about a week and a half later it starts grinding gears. turns out it was a 4cyl tranny. so we got a t-5 from stangparts.com they put it in there, thats when i got more comfortable with the car and i noticed it...o yea the gears came w/the car. i have roatated it twice. however there are 8 holes on the rear end. four are raised and four are kinda sunk down. im your not sure what im talking about lemme know. the d/s was bolted on the raised holes so thats how i rotated it, can it be bolted on the lower ones? i dont think the bolts are really long enough.

i wish i could find a store that still sold the alums for 160, but they are all 250 or whatever now, now i have to resort to ebay.

also since i rotated it and i didnt remove it, does the front yoke just slide out?..dumb question i kno.

so as i see it now
Rebalance: 0
Aluminum: 2

thanx...keep em comin

 

[battyice]

Another question: Have you checked to see if either if your u-joints are binding? A bad u-joint can cause horrible vibrations.

 

[FrdMustangCpe]

how would i do that? would that shop that i took it to today look at it?

and wouldnt that be at all rpms and not just above 2500?

 

[dromeda]

I'd definitely go with an all new FMS aluminum one. If one of those u-joints fails, your car is in for a world of hurt.

 

[battyice]

A vibration from bad u-joints is most noticeable under load (or acceleration, as the case may be). My mustang used to have a nasty viration whenever I would punch it in 2nd or 3rd. I replaced both u-joints and it's been great since.

The u-joints themselves are pretty cheap, I would change them and see if your problem goes away. If you change them and it still persists, you're out like $25. If you just want to check them you can remove your driveshaft and swivel the yokes around to see if the u-joints bind at all.

Or...you could just purchase the aluminum d/s and eliminate all the guess work since most of them come with new u-joints anyways.

 

[FrdMustangCpe]

Or...you could just purchase the aluminum d/s and eliminate all the guess work since most of them come with new u-joints anyways.

thats kinda what im thinkin. now that you mentioned binding, i was thinking that the sound is coming from the rear u-joint, then you can feel it throught the shifter. i will take it off tomorrow, rotate it again and check for binding. also any clue about which holes the bolts should go into? the raised or sunk down ones?

thanx
-Mike

 

[Daggar]

You can't go wrong with a "new" aluminum DS complete with "new" U-joints. If you're buying from ebay then do what you can to not buy someone elses hedache. It's a rather inexpensive investment and I'll wager that you'll end up doing it in the end anyway.

 

[FrdMustangCpe]

Ebay auction for a ebay 'store' $125
Anotherone $200
or 260 from jegs/summit

how bad could i got wrong with the first one?

 

[FrdMustangCpe]

bump

 

[jpctln]

That $125 one doesn't look like an FRPP driveshaft...I don't know if that means it's better or worse, but I'd take a guess that FRPP is better quality. I've been looking into getting one of these too.