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Old 07-14-2006, 09:40 PM
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Default Uh Oh!

Now that I am lowered I can feel a vibration or (light grinding), at certain rpm's when accelerating, coming from what feels like the rear end?
I talked with the Install shop and the mechanic said that some vibration is normal for "the trucks" after lowering. I have a one-piece aluminum driveshaft if that makes any difference?
For a 2/3 drop i sure feel like it got real low.
Any problem?
Normal?
What should i do?
Old 07-14-2006, 09:48 PM
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Not so sure that I'd consider that vibration "normal", and more than likely it can be remedied. You might just need to correct the pinion angle of the rear differential...you can buy pinion angle shims fairly cheaply. I know Summit sells them at a good price, and some of our sponsors may have them also. 4* shims seem to be the most common ones that people use.

I lucked out when I lowered mine...I actually had a vibration from 60-75ish that went away after I lowered the truck. I thought I was gonna have to get the driveshaft balanced (which I was gonna have done when I eventually did the 6.0/65E swap), but actually got lucky for a change
Old 07-14-2006, 10:46 PM
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Pinion angle is what it is. DC Justin was kind o'nuff to guide me installing my SS Cluster and verified it. The Vibration is very noticable when the driveshaft is under torque.

Stupid question: Who would specialize in setting a propper pinion angle? Is that somthing an alignment shop can do??
Old 07-14-2006, 11:24 PM
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Bill - There are a couple ways to fix the problem if it is the pinion angle.

You can but the pinion angle shims, in either 2 or 4 degree sizes. If I were to go this route, I would just add the 4 degree shims and go from there. I have 4 degree shims in my truck. I did it to angle the rear end more to the ground so I could possibly get more traction.

I also have a carrier relocator braket made by DJM. Not sure if it will work with a 4wd or 1 piece driveshaft, but it also helps with pinion angle by raising the carrier bearing up higher. You actually probably dont have a carrier bearing with a 1 piece driveshaft.

These are just some suggestions.
Old 07-14-2006, 11:27 PM
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Did some research, you cant use the relocator bracket, only for 2 piece driveshafts.

Here is the link to the shims. I would go 6 degrees. The more you can get the rear end to face downward, the better trastion you are going to get in 2wd.

http://www.djmsuspension.com/Product...ype/Shocks.htm
Old 07-15-2006, 12:10 AM
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Thanks Jason! I'm going to have to find someone locally to get this done. I dont have the time, tools or temperance to do it myself .
Old 07-15-2006, 12:20 AM
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Originally Posted by trever1t
Thanks Jason! I'm going to have to find someone locally to get this done. I dont have the time, tools or temperance to do it myself .
Get the shims and I'll bring my jack, stands (if I can find them) and tools on over and we can swap them in and remove those 0* shims you have in there right now. They seriously look flat, like a 1/8" lifting block...

Edit: I didn't think of it when I was over there, but take it for a spin in 4wd too, to see if you notice anything there as well.
Old 07-15-2006, 12:23 AM
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I need to get this done before friday next week. Do you think I can pick up shims locally?
Old 07-15-2006, 01:04 AM
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check this out
http://www.rosslertrans.com/Tips/Pinon.htm
Old 07-15-2006, 11:48 AM
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call up whichever company you bought the drop kit from and see if they know. im sure your not the first to experience this.



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