FarmerBeau

iTrader: (2)

JK, whats your driveshaft made out of? Mines shitty AL and i must say, my wiener weighs more than it does. I think its like 22 guage. Will a stock steel driveshaft from another style truck fit ours? Oh yea, its a single piece. Hmmmmm?

I want something i know isnt gonna grenade without spending a fortune.

agreif

iTrader: (4)

Ahh, yes. I was pulling away from rice the other day (not as fast as I would have liked to) and only wanted to push it to about 95 before I let off to prevent another explosion. When calling the reputable DS makers (Inland Empire, Denny's, a place in MI) they all told me a steel DS 72" long like ours are would be worse for critical speed, which is what causes these to let go at high speeds.

No one I talked to could make another 5" AL driveshaft, best was a place in texas that was 5" and then necked down to 4" closer to the joints, which will lower the critical speed.

Some people can get the AL high speed balanced, but I know a lot of places can't/don't want to high speed balance the AL because of the welding. I read something on here a couple days about about a carbon fiber, still not sure about that.

All this being said, the critical speed for my DS is calculated to be 6200RPM, and mine gave out at 5000. So a BIG piece of this is how well it's balanced. here are the options I think.
1) Stock AL - high speed balanced and DS loops
2) Carbon Fiber - high speed balance
3) Create a frame support that will allow you to support the bearing in a 2 shaft design like the extended cabs.

FarmerBeau

iTrader: (2)

I work as a welder so the only thing that would worry me would be making sure a two piece was perfectly in line. Are the stock two piece for the excab the same size. It seems like the a built driveshaft is the way to go.

negativeswitches

iTrader: (15)

x cabs are about 1' longer

nonnieselman

iTrader: (10)

At what speeds are the DS letting go?? Ive had my truck up to 138 and it felt fine, but thats the first and only time. i think it was 5500or 5600rpms in 3rd..

agreif

iTrader: (4)

Mine let go at 5000RPM (124 for my gearing), but I know others have had them let go lower. It depends what year EC you have too, some have 2 piece (ok) and some have the single long driveshaft.

silver-mod-o

iTrader: (15)

my two piece had been fine... not even any high speed vibes... (not even around 140+)

FarmerBeau

iTrader: (2)

I never go rediculously fast. I will rarely go over 100 anywhere on the street or highway so im not worried about it letting go there. I am however worried about sticking my bitch on a dyno. I think that driveshaft will grenade fast!

nonnieselman

iTrader: (10)

so some ECs are ok for that high DS speeds? Because im goin to 4.10s soon, and i know its goin to be spinning even higher speeds? i have 29" tires.

FarmerBeau

iTrader: (2)

I am going with the same rear and my tires are the same size so i thnk a thrid gear dyno pull is out of the question.