ok, i'll rotate it 180 & then drag the driveshaft to a shop regardless. i preloaded the bearings to about 20 in lbs.

 

Driveshaft for sure! Hope you have better luck with your aluminum unit than I did with my steel one. Finally had to get a heavier gauge bigger diameter one made that was high speed balanced. The factory one came out at about 90 after the 4.10's and did $1700 worth of damage! Don't run it very fast until youve gotten it balanced.

 

Thanks for the heads up fast...that's my sweet spot. Around 90 its at it's worst. Im thinking im gna have to change to a steel shaft. Cant find anyone in town that can balance AND weld an alum shaft... WTF?

 

Update: None of the "drive train/drive shaft" shops here in Odessa could do a balance over 2,000RPM much less do any kind of Alum welding. Sending it to Drive Shafts Unlimited in San Antonio. Hopefully this will fix the problem.

 

Good deal.

 

your driveshaft is about to let go.

 

Just call driveshaft specialist and have them build you a real driveshaft

 

More than likely, that truck had 3.73s stock. There is no reason why that shaft shouldn't be able to handle 4.10s at 85mph. I have seen people drop the shafts when taking them out, and put a kink in the tubing. I've also seen the yokes damaged by improperly changing the u joints.

 

This truck has the gu5 code in the glove box. So according iamkeniff that's 3.23's... I would say that's a fairly significant jump in gear ratio. Had the drive shaft supported by a jack stand when we did the gear swap...stock u-joints. I'm gna have Nelson's Performance in San Antonio build me a drive shaft we I get the extra $$. Until then, just gna have it high speed balanced. Also got Corevette Servo on the way. Anybody have some good advice on best tranny for a future swap?

 

Performabuilt or finish line. Look to the right. I will be getting mine from one of them.