driveshaft make my car not safe to drive highway speeds?
 

hey guys im hearing alot of driveshafts snapping at higher speeds and its kinda making me nervous. im wondering it this only happens when people take the govener out of the car. will my car rev limiter or govener what ever the thing is called that makes you not go faster after a certain point kick in before i have to worry about it?

Highway speed isn't the issue. The guy who had the issue took the speed governor off his car, ran it up to 135 mph; I haven't heard of it being an issue across the board for the 3.7. How many times do you plan to run that fast? Even at the drag strip you won't hit that speed in a 1/4 mile.

+1

The issue seems to be in excess of 120, maybe 125 MPH.

Not to point out the obvious, but if someone has a higher ratio gear installed this speed limit will need to be lowered significantly.
The "speed limit" is really the RPM limit of the drive shaft, in other words it is the rotational speed when the natural frequency of the tubing is reached = splooey!

What rear gear is standard on a 6er?

Standard rear gear on the 3.7Ls is 2.73. 3.31 is a factory option and also comes as part of the Performance Package.

2.73 stock

3.31 on PP, most of the time, countries may vary.. :)

This whole DS thing is blown out of proportion, but it is what it is...

To OP: Please try the to use search on this topic as you will find there are lots of good threads on this with alot of information for you to follow up on if you really want the nitty gritty; the causes of the 'few' DS failure issues discussed by actual DS manufacturers (Shaftmasters) seem to be around issues on modded cars on a dyno, where heat issues are highly suspect; The one guy who 'just so happened' to capture his DS exploding on camera on a 135 roll.. Makes you wonder about his treatment of the car. Interesting timing, in my opinion.

There are numerous guys here that take these v6's out to the dragstrip with bolt-ons and still have the OEM shaft - no issues.. If you're worried about a DS exploding if you happen to get above 125 (118 is the governed limit btw...).. Get a yaris so you don't have to worry about going twice above the speed limit in the first place. Or don't put so much faith in a youtube video. Or, if you are modding this car for enjoyment - move that DS higher to the top of your list, especially if you're going to go FI or do taller gears any time soon.

To Op's original Q: Yes, when you are doing near twice the speed limit, your governer (@118) will kick in and keep your car out of any DS danger. If it doesn't, I'm sure you can take it up with Ford once you explain what you were doing @118.. :) (Try to have a dragstrip slip handy for that one)

I wouldn't be so quick to say "as long as its kept under the limiter your d/s will be ok". American Muscle was cruising down the highway, 75-80mph when theirs let go.

But what Jayvee is saying for the most part is right on OP. I dont personally think theres anything you can do to prevent the d/s from exploding. Its of my opinion that its based on the integrity of the particular part your car gets, not so much the treatment the car gets.

Example: My car has 60+ passes on it, lots of street runs, LOTS of wot runs in general, 135mph during a run against a srt10 ram, 142mph on the 3 dyno pulls, all on the stocker driveshaft.

Duplicate

Let's play with a couple numbers and compare.

Governor set at 118MPH according to above post.
Axle ratio standard = 2.73 according to above.
Optional ratio = 3.31 according to above.

Is the speed governor set to a lower speed because of the higher gear ratio?

What size tires was the car sold with?

With these numbers we can figure a few things out.

Lets get the facts straight.....heres the real information

http://v6mustangperformance.com/tips...shaft-failure/

http://v6mustangperformance.com/news...haft-failures/

http://v6mustangperformance.com/news...sues-resolved/

http://v6mustangperformance.com/news...-transmission/