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Discussion Starter #1
Anyone have this happen? It is the yoke on the rear of the driveshaft. When flexed it will just come in contact with the fuel tank.

I have a 1350 JE Reel driveshaft back there and had not noticed it with the 13010. But at the same time I switched lifts to my Poly lift.
I am wondering if I really need an adjustable rear trac bar.
It seems that my axle is 3/4 over on the passenger side at rest and maybe that 3/8" is the clearance needed to clear the fuel tank. I am not sure. Never had this happen on this before.
It does not seem to be rubbing much but it could be that the rubbing is stopping to to shift more.
I wheeled with this lift once on a night run and noticed no problems like this. Almost seems as if it just started on my last offroad outing. But it does sound like when you grab an inner fender well with your tire so it might have been i was thinking that is what it was on its shake down run.

anyone ever run in to this? Any ideas?

I did check that both rear arms were the same length and the axle was not angled to one side or the other.
 

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Phil had this problem with the rear drive shaft rubbing his Rock Hard Gas Tank Skid. Can you trim or use a BFH to give you more clearance? Also, are you using a rear axle mounted track bar relocation bracket? The higher roll center will cause the axle to shift more in the direction of the axle track bar mount when, in this case of the rear driver's side stuffed and passenger side drooped. This would swing the opposite way of the fuel tank though.

First, I think you need to center your axle. You have a couple of options. You can either use an adjustable track bar or an axle mounted relocation bracket. I have the Teraflex in the rear and it has 3 or 4 different holes to mount the track bar in for adjustment if you don't have an adjustable bar. I'm not sure about the Poly one. I have theirs in front, but there's only one place to mount the track bar. I'm also using adjustable bars though.

If you center your axle and it's still rubbing see if you can create some clearance by cutting or wacking.

On another note, if you haven't done so yet, definitely get axle mounted track bar brackets front and rear. You will be amazed how much better it drives when you raise the roll center. I've had the Poly one in front for a while, but I just installed the Teraflex one in the rear. They gave it to me free, because when I bought my lift they were using a frame drop bracket and changed the design. I noticed a big improvement when I installed the front, but nothing like adding the one in the rear. Body roll is all but gone in the corners on the road. I'm sure it will help offroad in off camber situations to.

Also using a relocation bracket will level your track bar out and the axle should swing as dramatically when compressed or drooped. Helps with bump steer too.
 

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Discussion Starter #3
I have a full Poly Synergy III kit.

I have an axle mounted poly rear bracket.

I am thinking adding an adjustable rear trac bar would give me the clearance i will need to center it up and not rub.

To be honest I have the stock skid on the gas tank and it has no room for "clearance" If I got an aftermarket skid this may become worse.
 

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I have a full Poly Synergy III kit.

I have an axle mounted poly rear bracket.

I am thinking adding an adjustable rear trac bar would give me the clearance i will need to center it up and not rub.

To be honest I have the stock skid on the gas tank and it has no room for "clearance" If I got an aftermarket skid this may become worse.

If you're of by 3/4", that's a bunch. I think an adjustable bar will take care of you.
 

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Discussion Starter #5
If you're of by 3/4", that's a bunch. I think an adjustable bar will take care of you.
i agree, but split the difference thats only 3/8" more clearence
 

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Give Poly Performance a call. They are the experts...
 

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I have a 4.5" Poly lift and 1310OE drive shaft and it rubbed hard on my RockHard4x4 gas tank skid. I have an adjustable track bar and my axle is centered. I first clearanced the RH4x4 skid where it rubbed but that didn't help much. I ended up extending the rear bump stops which seems to have solved the problem. This obviously reduces up travel a little, but doesn't really effect down travel or overall flex.
 

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Discussion Starter #8
I have a 4.5" Poly lift and 1310OE drive shaft and it rubbed hard on my RockHard4x4 gas tank skid. I have an adjustable track bar and my axle is centered. I first clearanced the RH4x4 skid where it rubbed but that didn't help much. I ended up extending the rear bump stops which seems to have solved the problem. This obviously reduces up travel a little, but doesn't really effect down travel or overall flex.
what part of the tank was it rubbing on? Mine is not centered as of yet but I am not sure it will fix the problem. It appears to rub lightly on the tank but that may not be the case once i move it over I do not know how much pressure is on the tank. It is rubbing at the bottom 3" of the side of the tank.
ill order an adjustable trac bar and see if that solves the issue. If not then Ill go the next route.
 

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what part of the tank was it rubbing on? Mine is not centered as of yet but I am not sure it will fix the problem. It appears to rub lightly on the tank but that may not be the case once i move it over I do not know how much pressure is on the tank. It is rubbing at the bottom 3" of the side of the tank.
ill order an adjustable trac bar and see if that solves the issue. If not then Ill go the next route.
Mine was rubbing in the same place, but I have a RH4x4 skid plate which obviously exaggerates the issue. I would definitely see how you do by centering the axle before trying anything else.
 

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I’m having the same issue with the pinion flange rubbing on the stock gas tank skid. It is rubbing hard, to the point I am afraid anymore and it will go through the skid and into the tank. Build as follows.
Teraflex 4” lift with 8 flex arms.
Tom Woods 1310 drive shafts with pinion flanges.
JKS adjustable rear track bar, axle is centered to within 1/16”.
Track bar frame end mounted in the stock location and reinforced.
Track bar axle end relocated up about 3-4” in custom bracket.
So what have you guys done to solve this problem? I hate to have to extend the bump stops but if that is the only solution I guess that is better than a hole in the tank. Phil, how much did you extend yours? Or have you come up with a better solution? Any way to move the gas tank over? Any way to modify the tank? Or an aftermarket tank? What about flipping the track bar mounts, frame mount driver, axle mount passenger. Would that make the axle swing away from the tank instead of into it? How would that affect the suspension and handling?
Any help would be greatly appreciated, thanks guys.
 

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I'm also working to resolve this. Are you using front and rear sway bars while you are flexing and hitting tank Bugeater?
 

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Mine does this and the axle is perfectly centered. I have Woods shafts and it snaps off the zerk on the rear u-joint. It's worse with upgraded skids. I had a Rockhard on there (overlaying thes tock skid) and cut a piece out for clearance. I now have a Poly skid on there and it's hitting it just a bit. I tried a flat surface zerk, which is OK but the yoke still contacts it a bit.
 

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Phil, how much did you extend yours?
I'm running King bumps right now so can't say for sure, but I did extend the rear bump stops quite a bit to get rid of the problem.

Or have you come up with a better solution?
When I had a frame drop bracket instead of an axle rasied bracket I don't recall having the problem. Not the best solution from a geometry point of view, but may be worth trying.

Any way to move the gas tank over?
No.

Any way to modify the tank?
No.

Or an aftermarket tank?
Genright offer a tank that fits up at the rear (like a TJ tank). I believe you can use a 2005+ TJ tank in the same location and retain all the EVAP stuff. A fuel cell in the trunk.

What about flipping the track bar mounts, frame mount driver, axle mount passenger.
You want your track bars opposing each other, so if you did that to the rear you'd have to swap the front, which would be way more work than it is worth.
 

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Same problem. No way could I put on an aftermarket gas skid if i chose.

Tom Woods 1310 driveshaft
TF 4" lift
- bumpstop extensions removed
- swaybar links moved to outside
TF rear trackbar with TF raised axle side bracket

Assuming my eyeballs and measurement technique are spot on, my axle is 1/16" to passenger. As of now I'm hoping I've carved enough out of the skid that, I'm "clear". This thread did just inspire me to paint the contact area to see the contact severity remaining after next flexy trip.

 

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That can't be good on the pinion bearing.
 
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