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Pinion Shims (again) for nnbs 4/7

6368 Views 31 Replies 7 Participants Last post by  nox
I know I keep asking this same question, but I can't find anything through the search.

Where can I get shims that will work with my Beltech flip kit? I got a set of ground force shims but I can't get the axle saddles to seat on the pin with them on. I still get a slight vibration but I think it may be my paranoia kicking in as both my wife and a good buddy of mine say they don't notice anything.

Do other people with nnbs 4/7s use shims or trans spacers? Right now I have neither installed. The trans points down ~ 5* and the pinion is roughly 0, maybe down 1*. Operating angles are 2-3* at both ends. I removed the trans spacer that came with my it because the vibe was worse with it in, although it did get my angles closer.

Thanks in advance.
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767 Posts
You probably need a longer leaf spring pin. Then grind it down so it goes through the shim, then engages the flip kit brackets. If you have an ext. cab, you can adjust your bearing carrier. You said your working angles are 2 to 3 degrees, Is your driveline pointing down or up? Finallly, are you trying to raise the pinion or lower it?
 

· rox
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240 Posts
Discussion Starter · #3 ·
Ds is pointed down towards the rear. My thought was to raise both the pinion yoke and the trans yoke to get the angles closer to being on the same plane.

So do I need to flip the pin back to stock? Right now the pin is reversed with the threads pointed downward.

Nnbs has a one piece driveshaft, no carrier bearing to mess with.
 

· rox
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240 Posts
Discussion Starter · #8 ·
pics of what? I put the shim in with the high end in the front and it raises the axle saddle enough that it doesn't make good contact with the leaf pin. I don't know how I could get a pic of that.
 

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Ds is pointed down towards the rear. My thought was to raise both the pinion yoke and the trans yoke to get the angles closer to being on the same plane.

So do I need to flip the pin back to stock? Right now the pin is reversed with the threads pointed downward.

Nnbs has a one piece driveshaft, no carrier bearing to mess with.
you want both angles pointing down towards the center of the truck. trans about -3* pointing down towards the rear end and the rear end 0-3* pointing down towards the transmission. under acceleration the pinion will ride up the ring and set the angles about perfect.
 

· rox
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240 Posts
Discussion Starter · #15 ·
rear yoke is at 0 or -1* (points down towards the front wheels)
trans is at -5* (points down towards rear wheels)
shaft is at -7* (down towards rear wheels)
 

· rox
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240 Posts
Discussion Starter · #19 ·
do you have measurements on what your angles are though? Mathematically, putting them in like you did would make my truck worse. Could be from the different brands of flip kits or who knows...
 

· I don't have a truck
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19,163 Posts
I just figured that lowering should make the driveline flatter than stock right? So fat to the back would point the angle down more, making it more of an angle?

Idk.... But it worked for me.
 
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