Whats better then the aluminum D.S.

[willys1]

I have the alu. DS,its alot better then the stock one(alot less vibration) but I still get drivetrain vibration under hard excelleration.What would be the next step up? I see ads for chromemolly DS's,but are they better?

 

[raph130]

*

 

[willys1]

you shouldn't be having vibration even with a stock driveshaft *if its rotated correctly* and aftermarket gears. i would check your transmission mount, and the d/s bolts and check if the pinion nut is loose or not. unbalanced tires can cause vibration also. there are 4 driveshaft positions.

When I put gears in,the vibration was really bad at high speeds.The alu. ds helped out alot.But there is still vibration.I'LL check that stuff,but the car has low miles on it.Maybe the mount is dry rotted,but I doupt it.

 

[cevtv]

Check your harmonic balancer.........the stock ones suck!

 

[SlowGT]

If the vibration started after you put in gears, I'd be having a good hard look at the pinion nut. Don't be too surprised if it needs to be tightened up.

 

[HISSIN50]

rather than look into moly or CF shafts, i would address the problem. a driveline shop should be able to dynamically balance the moving drivetrain (put it on a lift and balance the entire rotating assembly). that is the route i would take.

good luck.

 

[willys1]

Check your harmonic balancer.........the stock ones suck!

The stock one does s@ck I just put a new one on and it runs so much smoother!! Hissin50,thats a great idea,but what exactly is a driveline shop??

 

[89MustangGX]

It's pretty common to have a vibration after a gear change because the ds is now spinning a lot faster, and most of us never spun it that fast before.

If the Aluminum ds didn't fix the problem and it wasn't there before gears, I would definitely look for a problem in the rear and not the ds.

 

[willys1]

Im putting my 373's back in (January) so I will check it then!! Thanks

 

[HISSIN50]

Hissin50,thats a great idea,but what exactly is a driveline shop??

check the phone book. often the shops do driveline repairs (after frame work) or work on big rigs (those DS's take a beating). some people have had a hard time finding one. if you cant find one, call some places and ask if they know of a shop that can do dynamic driveline balancing.

also, Adam had a good point about possible issues inside the pumpkin.

 

[87'GTstang]

also, Adam had a good point about possible issues inside the pumpkin.

In respect to gear install, if it vibrates under hard acceleration then it could very well be that something isn't tightened down, the pinion preload isn't correct or even the pinion nut isn't tight enough. I would have to point fingers at the gear installation.

 

[willys1]

check the phone book. often the shops do driveline repairs (after frame work) or work on big rigs (those DS's take a beating). some people have had a hard time finding one. if you cant find one, call some places and ask if they know of a shop that can do dynamic driveline balancing.

also, Adam had a good point about possible issues inside the pumpkin.

ok,theres actually a few big rig shops in my area.

 

[BlackFox5.0]

Try rotating the DS 180* on the rear end. That solved it for me, twice.

 

[willys1]

The guy that installed my gears has been doing tranny's for 40 years,he has 3 race cars and has been racing here at my local track since the 60's.He used to be in the staging lanes with Don Garlit.When Garlit broke the record for the first person to break the 200mph bearier,he did it at this track(just a little trivia) So I have all the confidence in the world with his work.But I will have it checked

 

[willys1]

Try rotating the DS 180* on the rear end. That solved it for me, twice.

The whole unit,or just the u-joints?

 

[BlackFox5.0]

The whole unit,or just the u-joints?

Unbolt the DS from the rear end, spin the wheels, till the DS mounting surface spins 180* and re bolt the DS back on. Then test drive.