What is the max rpm on the aluminum driveshafts? I saw a post that said something along the lines of "most dyno shops wont dyno something w/ an aluminum driveshaft in 3rd bc it will blow up at 130". well, the speed will change dependent on gears and tire sizes so am i at risk? 35's w/ 4.56's. Cruise at 80 a lot... sometimes hit 100ish just messing around on the highway going out of town.

 

There is no speed at witch it will blow up. There are a TON of variables that go into DS problems. Just search and you will find all you need to know and some fun vids of shafts blowing up on dynos

 

good point, didnt think that through all the way lol.

 

it doesnt pop at 130

i know cause i've run all the way to 140 on the button more than a few times and i;m still here.

Knocks on wood

 

i depends on how much of a bind it is put in!!!!! as for when its gonna break

 

my truck went to 160ish i think it was on the dyno and it was fine. the speed was per hpt log.

 

It's 95% dependant on the driveshaft length. All the guys that have had it last past 130+ don't have the 72" long driveshaft, which is what most blown ones here have been. The long ones have a low resonance frequency, so they bust much earlier than the shorter ones. Technically, a perfectly balanced 72" should go to 6100, but the factory isn't going to spend the extra money to do that for the 1% of us that override the speed limiter and go faster than that (https://www.performancetrucks.net/fo...d.php?t=364990).

 

I had a 83 inch drive shaft and had it up to 150 +/-. I would not recommend that ever because the rear end starts to shift and I ended up knocking the drive shaft on a crossmember. Fortunetly I did not break it but I'm sure if I were to even get close to that speed again I would grenade the thing. Mine started to vibrate at about 115.

 

83" one piece? what kind of vehicle?

 

Or 82" not sure...it's the CC in my sig.