I had that happen to me with the one piece aluminum DS was on the freeway had a M5 fly by me so I thought I'd see if I could keep up with him next thing I know I heard a big boom thought it was a blow out lucky I was near a exit got off and truck wouldn't move look under the truck and DS was gone tranny fluid everywhere...now I dont go over 100mph until I can get one built... Lucky it was still under warranty... is ur truck under warranty? they'll fix it....

 

that sucks man. hopefully they can help you out and get you on the road soon.

 

The drive shaft on my truck is a one piece aluminum shaft. If any of you live within distance of High Speed Performance, I suggest you check there shop out. The guy has been doing performance kits on cars/trucks for about 30yrs. Very nice and smart guy to work with. Some of the cars he had in his shop yesterday were a 1971 all maching number 1971 Chevelle SS, 1971 Maverick, 1970 Challenger R/T SE Hemi, just to name a few. I am waiting on a quote from Mike on the tranny, exhaust, and after market drive shaft. I will let you all no the estimated damage cost when I hear from him today.

 

Sorry to hear that man. Precisely the reason I do my dyno tuning in 2nd gear. Have only done one in 3rd. Will put out lower numbers for the 2nd gear customers, but the risk of snapping is not there.

 

It doesnt matter how fast your wheels are spinning(speedo reading), it depends how fast your driveshaft is spinning. Your 4.10's are making the shaft spin faster at the same speed than 3.42's are, which means you are MORE prone to throw a shaft with 4.10's than 3.42 gears(on the street).

On the dyno in 3rd gear, 6000 engine rpm is 6000 driveshaft rpm, no matter what gears you have in the rear. Your tires are less likely to delaminate, but your driveshaft isnt protected from damage.

These trucks are ENGINEERED to never see over 98mph. Which is about 4500 rpm in 3rd(1;1) with 4.10's and 30"tires. (4.10s are the worst case secenario from GM in a 1/2 ton truck from the factory) Some guys are pushing to 6900-7000rpm. No wonder shafts let go sometimes.
This is why I run a custom shaft.

driveshaft loops help keep the under truck carnage to a minimum when these shafts let go.

peace
Hog

 

I am planning on replacing the stock driveshaft with a custom aluminum shaft and heavy duty U-joints. As far as installing a driveshaft loop, if it does decide to snap again, I don't want to loose the tranny. At least with a loop it should keep the shaft from hoping around and tearing up the bottom of my truck. I had my truck turning 6600rpms before I installed the supercharger; that is why I decided to go with a dyno tune so I can see where the truck peaks out hp wise. There is no reason for turning that kink of rpms, if my truck is producing peak hp at let's say around maybe 6200-6300rpms.

 

Click the link in my sig. I know how you feel....

 

Get a steel shaft, not aluminum. Steel has a higher critical speed than aluminum and should stand up to higher speeds. There was a whole thread about driveshaft failures and what causes them, maybe someone can dig it up.

 

Damn, that is exactly the same path my truck took. It sounded just like yours and then wamm!!!!. Scared the **** out of me at first. luckily all it took with it was the tranny and exhaust. The underbody wasn't touched to bad, could have been worst I guess. I am hoping to get my truck back together in the next week or so. Garage seems lonely without it

 

Here is how I fixed mine...3.5" OD Aluminum