Something went bad

Nathan Stanfield

TJ Enthusiast
Joined
Feb 6, 2018
Messages
103
Location
Wichita, KS
I finally got my front Dana 30 HP that someone gave me done and put on the TJ last night. A few months ago I swapped the rear for a Ford 8.8, SYE, and rear custom drive shaft.
Today we set out to take it for a test and look at the damage caused by yesterday’s tornado.
Everything seemed normal at first, then we drove 5 miles on a dirt road, then we turned onto a paved road and everything went to hell.
The Jeep vibrated so much that I felt like I was on a massage table. This continued till I got home and smelled the familiar stink of ATF. I climbed under and saw that ATF was leaking out of the seal around the output shaft. Not much but enough to tell me somethings up.
The front drive shaft has over 120k miles on it and has been the possible source of strange sounds lately. (Angry sparrows but not all the time)
I pulled it off and went for a drive. All the way up to 70 mph on the highway the Jeep drove smooth as a Cadillac. I never went any faster than that.

I’m going to guess that the front drive shaft is done for, but do you guys think tha I might have messed something else up from all the vibrations? I cleaned up the ATF and so far nothing else has leaked out.

Once it started shaking I was driving home no matter if I wanted to or not because I was out in the middle of nowhere, so probably did about 80 miles with it shaking.
Now I want a Yukon spin free kit even more.
Thoughts?

Thanks!!
 
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How was the front shaft length when on the ground? Generally the stock shaft is too long when swapping in a HP 30.
 
How was the front shaft length when on the ground? Generally the stock shaft is too long when swapping in a HP 30.

The length seemed fine to me when I put it on.
I have a 3.5 inch lift so I figured the HP would put everything right about where it should be.
From looking at it I thought I might need to bring the pinion angle down a bit, but when I got it home and put the gauge on it showed to be less than 1degree difference in pinion/shaft angle.
I will probably just measure everything and then call up the local drive shaft shop this week and have them make me a new one.