SOA rear Driveshaft vibrations

[Vanilla Gorilla]

Vehicle is a 1984 FJ 60 with stock motor and 4spd trans & Tcase. The SOA was done by the previous owner who is a competent welder etc. It has Chevy 63's in the rear (track bar to come) and some OME DAKAR springs upfront with extended sway bars on 35's. I am experiencing a LOT of 2nd and 3rd gear vibrations but vibrations at all speeds.The output shaft is tight and appears to be straight, as well as pinion flange. All vibrations goes away when the rear driveshaft is removed and ran in 4HI. I measured the rear pinion angle at +1 degree and transfer case output at -8 degrees. Currently a stock shaft is in place with no dents etc. Looking for recommendations as to the most cost effective fix. Any experience using a IFS front driveshaft and take the double cardon and multi drilled flange or am I better off just having a CV shaft built.

Thanks for the information.

 

[gnob]

The ifs DC needs to be clearanced. The 84-85 doesn't.

That being said, both my dl are mod'd IFS DCs built by High Angle in Paradise cal.

 

[2ndGenToyotaFan]

Maybe have the shaft checked for balance?

+1 to -8 decrees sounds like 9 degrees difference, that could also be a problem. Ideally you want the to flanges to be at the same angle.I know they make angled shims to correct leaf spring-axle issues.

Could it be that the stock shaft is just a hair too short to engage the splined area enough for a solid shaft, and it's flopping around a bit?

How are the U-Joints doing? If they are going bad it could be a cause as well...

Good luck!

 

[jamister1]

If you're local run it by walker driveline, he can glance at it still in the truck and tell you what it needs.

 

[Andersej]

9 Degree difference seems too excessive to me, I ran into some s*** Napa U joints here recently that I had to replace even though I just replaced them....