Installed Shaftmaster Aluminum Driveshaft, Serious Vibration Problem

[COYO TT]

Ive had my shaftmasters up to 130-140mph and is like a dream

 

[Rob72]

You'd better watch out for those eastern shore coppers. Those guys show no mercy.

 

[RLF9409]

They got back to me with what was wrong with it. They installed it on their balancer and checked the runnout and balance. Their not quite sure how it happened but the runnout at the trans. end was excessive causing an imbalance issue even at low rpm's which is very unusual. These things happen, there customer service is excellant.

Are you referring to your shaftmaster DS or your new one?

I have a minor vib starting at 90+. It is minor but noticeable, shaftmaster as well. put in a Adj UCA and it helped a little.
I'm in Germany so getting it balanced right now is out of the question. I'll have to wait until I get back in the states this summer. Of course I won't be able to drive it at 100 mph legally anymore

 

[levelbelow2000]

Are you referring to your shaftmaster DS or your new one?

I have a minor vib starting at 90+. It is minor but noticeable, shaftmaster as well. put in a Adj UCA and it helped a little.
I'm in Germany so getting it balanced right now is out of the question. I'll have to wait until I get back in the states this summer. Of course I won't be able to drive it at 100 mph legally anymore

my shaftmasters one. Im rocking the stock one now

 

[wbt]

Installed mine this weekend and it is smooth as a baby's butt. Also installed the RAM 9.5" dual disc clutch with alum/flywheel. Very pleased with all the new parts.

 

[908ssp]

I got my PST drive shaft today. I'll get pictures soon the thing is amazingly light. With only a universal joint at one end and CV joint at the other it does away with the huge heavy sloppy sliding joint. Very cool.

 

[wbt]

I got my PST drive shaft today. I'll get pictures soon the thing is amazingly light. With only a universal joint at one end and CV joint at the other it does away with the huge heavy sloppy sliding joint. Very cool.

If the slip yoke was the issue then everyone would be returning their Shaftmasters D/S and they would go out of business.....

By your account, a hard launch at the strip will cause an issue every time. This is simply not the case. Those who had a vibration problem posted that it was due to the shaft being out of round and Shaftmasters agreed to send them a replacement unit.

The slip yoke design is much stronger than the CV joint and less prone to failure. Guess where the stock D/S breaks....at the CV joint.

In the manufacturing business shit happens. Sounds like Shaftmaster's customer service stepped up and did all they could to ensure the consumer was happy. Can't ask for more.

 

[908ssp]

A true one piece drive shaft. No slip joint or adapter plate.

 

[wbt]

A true one piece drive shaft. No slip joint or adapter plate.

....and the Shaftmasters uses no adapter plates. What is the point of this post?

 

[kdanner]

A true one piece drive shaft. No slip joint or adapter plate.

The slip is in the CV joint. If there was no slip joint the suspension couldn't move.

 

[908ssp]

Right so the PST shaft has a CV joint which by its very design has some length change and an universal or carden joint. Other driveshafts have two carden joints and a slip joint which if there is any slop in in it causes the whole shaft to wobble causing vibration. Plus universal joints are very sensitive to alignment. CV joints don't have that problem they don't need to be aligned as they are constant velocity joints by virtue of their design. Look I don't sell driveshafts you want to buy 100 year old technology and read almost every day about vibration issues fine with me.

 

[wbt]

Right so the PST shaft has a CV joint which by its very design has some length change and an universal or carden joint. Other driveshafts have two carden joints and a slip joint which if there is any slop in in it causes the whole shaft to wobble causing vibration. Plus universal joints are very sensitive to alignment. CV joints don't have that problem they don't need to be aligned as they are constant velocity joints by virtue of their design. Look I don't sell driveshafts you want to buy 100 year old technology and read almost every day about vibration issues fine with me.

You want to run something that is more prone to break then that is cool too.

As mentioned, the issue was noted to be with run out. Had NOTHING to do with the slip yoke. In fact, when I installed mine, it was extremely tight on tolerance. There was 0 wobble except in the u-joints where there is supposed to be movement.

Any other insightful wisdom?

Shaftmasters makes a great product. There was a manufacturing issue and they took care of their paying customers in the manner they wished.

 

[kdanner]

Right so the PST shaft has a CV joint which by its very design has some length change and an universal or carden joint. Other driveshafts have two carden joints and a slip joint which if there is any slop in in it causes the whole shaft to wobble causing vibration. Plus universal joints are very sensitive to alignment. CV joints don't have that problem they don't need to be aligned as they are constant velocity joints by virtue of their design. Look I don't sell driveshafts you want to buy 100 year old technology and read almost every day about vibration issues fine with me.

I see a U-joint on the other end, so I guess you bought 100 year old technology too.

 

[cobra mike]

I don't have a shaftmasters, but another companys 4 inch shaft, put it in got it up to 110 and smooth as butter, put the car on the dyno, feels like its going to shake the car apart, now on the road it feels like its vibrating, mine you have to change the flange, so im going to send it back to be checked soon..

 

[BMR Tech]

The never ending driveshaft saga.

That reminds me, I have a carbon fiber D/S right here next to my desk, never used on a car. If someone is interested in it, shoot me a PM

 

[KJGT]

A properly sized CV can be plenty strong, its advantage is it can work bind-free at greater angles - something a cros type u-joint can not do.

As far as the slip joint, any car with regular slip joint in the trans taihousing has play, especially after a lot of miles when the bushing wears and you dont hear about then vibrating. If the slip joint is on either end I dont see an issue, if you put it right in the middle thats a different story. IMO its the angle thats causing the vibration and thats why Ford went a two piece. Some people dont feel it, stock bushings absorb a lot, slight pinion angles, different rear gears (a driveshaft is turning a lot faster at 70mph with a 4.10 than a 3.15), different tires/wheels that may be balanced wrong etc.

I will probably do a steel PST in the future, I'm waiting to see how DSS's new CV joint shaft works out as well. But I may try a shadtmaser, hard to beat the price and since its a no hassle return if it doesnt work out then why not..

 

[MikeVistaBlue06]

Two things to check:

1. Did they align it with the marks on the rearend flange and the driveshaft? There should be a line on the driveshaft that will align with a mark on the rear end flange.

2. Where is the slip joint? If it is at the transmission, turn it around and put the slip joint at the rear end.

You can also opt for sending it back and getting one from Dynotech. I installed one not long ago and it is as smooth as a baby's ass. The slip joint on mine is at the rear end too.

HTH

Mike

 

[cyclerick]

I've also had my shaftmaster up to 140mph without any vibration

 

[wbt]

Two things to check:

1. Did they align it with the marks on the rearend flange and the driveshaft? There should be a line on the driveshaft that will align with a mark on the rear end flange.

2. Where is the slip joint? If it is at the transmission, turn it around and put the slip joint at the rear end.

You can also opt for sending it back and getting one from Dynotech. I installed one not long ago and it is as smooth as a baby's ass. The slip joint on mine is at the rear end too.

HTH

Mike

With this driveshaft the slip joint is at the trans side. There is no way to reverse it to fit as each end is a different flange mount. Also, the shaft is balanced and it does not need to be positioned in any particular way when installed. I.E. alignment marks, etc..

Love your avatar BTW.

 

[teal1993cobra]

Bad Vibration

I know I'm late to pitch in on this, but I have a Shaftmasters 3.5". I have solid bushings and it begins to vibrate pretty violently at 120mph on the road course. I just took it to the local driveshaft shop, balanced and it works perfect now. Hate that I had to do this, but I guess I didn't want to mess with rotating and trying to figure it out next race. I recommend taking it to a local shop before you spend hours and hours rotating, driving, repeat, ..... I didn't ask, but I'm sure Shaftmasters would have refunded my cost at the local shop, they seemed very nice on the phone.