supersub

iTrader: (25)

WOW! Big time pucker there!Back end raise up when it bounced of the pavement?

LMSeven

iTrader: (3)

You should be extremely happy that drive shaft didn't hit his car

James B.

iTrader: (1)

I have 29" tires and 4.56:1 gears and have been to 130MPH (6800RPM) many times on each of the two custom-built driveshafts made by Inland Empire Driveline in Ontario CA. (Got mine years before their deal with Summit racing to build shafts for F-Bodys)
First one was aluminum. Light but developed slipyoke bind ("clunk") after a while. Second one was splined and steel. Twice the weighy and strength, but never binds and doesn't ring like aluminum shafts do.

AKlowriderZ71

iTrader: (22)

I've been looking all over and asking about these driveline's critical speed, and the only input I get is "I took my truck to 150 mph once, and I'm okay, so you shouldn't have any problems." Well, I guess I'm too damn picky for that. When a driveline does let go, it's always at a high speed, and can take out the bed, gas tank, exhaust, transmission/t-case, etc, and may cause a wreck. Does anybody have any real info on this??

dewmanshu

iTrader: (4)

You aren't googling hard enough then...like James B. posted, I have an Inland Empire Driveline in Ontario CA. Denny's Driveshaft is pretty common among the truck guys also. If you google "critical speed driveshaft" you should find wealth of knowledge, let alone on here as well.

svensk

Seems like most of the busted ones I've seen lately are the aluminum ones.

ZZebes

iTrader: (10)

Umm his is steel






And here is my input on the subject, for whta it's worth

Stock shafts are balanced to right around 100mph beyond that you pass the critical speed, especially with the Aluminum beer cans in the extended and crew cabs. the pic i posted is exactly what happened to him around 6k in 3rd at 130 plus the minute he let off the gas and the shaft didn't have torque holding it straight it started to wobble and at 6k rpms that wobble did bad stuff quick.

My truck had a REALLY bad critical speed vibration around 120 with my 77in aluminum stocker and though it never broke it is twisted like a candy cane

i think people neglect these driveshafts to much and don't start quoting mythbusters on me cause those conditions were less than 1k driveshaft rpms not the 6k we see much higher surface speeds on the shaft, close to 60mph on the shaft, thats alot of speed for a 3" diameter shaft now obviously the surface speed speeds up with the bigger shaft for example the stock aluminum one is ~5" at the biggest part so at 6k rpms that is around 90mph surface speed BUT the rotational and inertial strength of the shaft increases thus raising the critcal speed. BUT All of this is completely dependent on the length of the shaft and the material.

Damn my head hurts

Long story short the first mod for anyone should be a driveshaft and a loop but everyone neglects them

dlt76028

iTrader: (13)

yea thats probably what happen except i didnt let off the gas it went to shift into fourth and thats when she let go...

BTW i thought it was aluminum too cuz its really light.

trxmxzx

iTrader: (7)

wow scary stuff right there, Ive touched 140 (which was stupid) and lucked out, but I do have a 2 piece so.....anyone break those at highspeeds, how are the 2 piece ones for strength?

ZZebes

iTrader: (10)

Nope just really shitty steel lol