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8.8 with UMI adjustable torque arm problems

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Old 04-13-2020, 12:32 PM
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8.8 with UMI adjustable torque arm problems

I am having issues when trying to finish my 8.8 install that the UMI adjustable torque arm is hitting the trans tunnel and doesn't allow the rear to completely go to ride height. I am considering cutting the rear

mount to be able to use the second set of holes pre drilled from UMI to bring it inboard some. Has anyone else had issues when combining an aftermarket rear with an aftermarket torque arm
Old 04-13-2020, 03:10 PM
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Re: 8.8 with UMI adjustable torque arm problems

UMI replied and said the inner bolts are for those situations where the arm sits to far outside and needs to be moved inward. going to cut off the outer bolt section and modify it to use the inner bolts

Old 04-13-2020, 06:13 PM
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Re: 8.8 with UMI adjustable torque arm problems

Finally is that with the outer holes machined off and contour matching original it fits tight and perfectly. Shout out to UMI for there quick reply and great parts. Guess other than the obvious would be to include the details of the extra bolt holes in the brochure they send in the kit but still kind of

obvious when you really look at it compared to the factory arm
Old 04-17-2020, 06:39 AM
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Re: 8.8 with UMI adjustable torque arm problems

When dealing with aftermarket parts, modification is common. The 8.8 is a recent offering and I'm sure wasnt tested during development like the more common 9", 12 bolt and s60.
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Old 04-18-2020, 06:11 AM
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Re: 8.8 with UMI adjustable torque arm problems

Was your rear end centered and do you have an adjustable panhard bar? Chances are thats your problem

Originally Posted by 85Z28NOS
I am having issues when trying to finish my 8.8 install that the UMI adjustable torque arm is hitting the trans tunnel and doesn't allow the rear to completely go to ride height. I am considering cutting the rear

mount to be able to use the second set of holes pre drilled from UMI to bring it inboard some. Has anyone else had issues when combining an aftermarket rear with an aftermarket torque arm
Old 04-21-2020, 01:04 PM
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Re: 8.8 with UMI adjustable torque arm problems

If you measure the distance from center line of the pinion to the center of the bolt holes this can tell you how far the TQ has shifted to the drivers side. I can provide this measurement if need be. This is a common issue with most aftermarket rear differentials. I had similar issues when I installed the 8.8 I built with a modified Hiltsy mount. I did however adapt it to fit an SN95 housing since it was the correct width and the pinion was centered. I did end up masaging the floor some on my car since the TQ i had was rubbing with the factory rear. I have the Global West Track Link.
Old 04-21-2020, 02:08 PM
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Re: 8.8 with UMI adjustable torque arm problems

I know I am not using either piece that you are. I too had to modify my founders mount to fit my ford 9 inch by cutting the mount to move to the most outter holes to move the mount inward to clear the tunnel.
Old 05-09-2020, 09:21 AM
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Re: 8.8 with UMI adjustable torque arm problems

Most everyone I talked to with aftermarket rear ends have had to cut the mount to clear as UMI recommended. Once I did this and adjusted my panhard bar to center the rear again I didn't have any more fitment issues

Last edited by 85Z28NOS; 05-09-2020 at 09:22 AM. Reason: spelling correction
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