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Driveshaft hitting exhaust downpipe

sportsguy

NAXJA Forum User
Here's the scoop:

1989 MJ - 5" in front, 6" in back

Last time out the grease nipple on the ds slip yoke ripped a hole in my rusty ol' downpipe.

This time, the grease nipple lost, the downpipe survived, but in addition to the nipple hitting, this time the u-joint ears (DS end) put a mighty dent into the downpipe too.

Static, the clearance is roughly 1 1/2" between the ds and downpipe.

(For those who may not know, the downpipe comes from the mainfold, down, then turns back (runs parallel to the ground for a bit), then crosses towards the pass side of the truck.)

The grease nipple is hitting the flat (parallel to the ground) part, while the u-joint ears hit the section just before this (and the bend) coming down from the manifold.

What's the solution?

Happy to provide any missing details.
 
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sounds like your front end is walking when flexing. Mine did the same only it hit my skid plate and I wasn't too worried about it. Check all your bushings/joints for play. Other than that, I don't know what esle to tell you.
 
i had to take a grinder to the flange on mine, as that is where my DS was making contact...
 
XJ Adjustable Track Bar ..$129.00

Made from solid stock for XJ's lifted

2 to 4.5 Inches

4inch_trackbar.JPG


Perhaps I'm over 4.5" up front and it's causing the front end to walk a smidge?
 
Bumpstops my friend - your axle moves to one side while flexing, think about it for a little bit - There is a link from the axle to the frame and the axle pivots around the ends of that link -
when flexing up the left tire - the right end drops and the axle moves to the passenger side...
At least that is all that i can deduce about my problem...
 
The down pipe on my STOCK Comanche has a big ole dent in it near the manifold mount flange...this was from running over a curb...guess I'll add bumpstop..
 
I had this problem due to DW after I first installed my lift. Took a while to solve the DW problem but in the mean time, the pinion on the front axle tore a big 'ol hole in the down pipe every time the axle danced. This is how I fixed that particular problem:

IMG_0003.sized.jpg
 
xtremewlr said:
I had this problem due to DW after I first installed my lift. Took a while to solve the DW problem but in the mean time, the pinion on the front axle tore a big 'ol hole in the down pipe every time the axle danced. This is how I fixed that particular problem:

IMG_0003.sized.jpg

Now THAT is a solution I can really like! Thanks a bazillion, man. :)
 
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