How high can i go with cranking and rear blocks?

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99GMC

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Indexed keys will allow you to crank more, but it's still going to ride like crap. A crossmember-drop lift is the next true stage up that will preserve a good ride.


I got under there today and the torsion keys are cranked with a 1/4" thread showing.

Will the crossmember-drop lift give me 1 more inch?
 

mdiacont322

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How big of a block can you fit under the springs with stock u bolts? i was gonna do 2" but is that too big for the u bolts?
 

99Yuk

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How big of a block can you fit under the springs with stock u bolts? i was gonna do 2" but is that too big for the u bolts?

I'm no expert, but I always thought that you shouldn't reuse u-bolts, ever. Something about they stretch on install, and they are one time use only. They are cheap to replace. Buy new nuts too. Just add 2" to the current length and go shopping. Canadian Tire, or Regional Spring will have the correct size.
I'll bet that guys here will have the correct size memorized and post it up.

Back when I added 4" rectangle steel stock blocks to a Jeep XJ, I had to use axle shims, add extra leafs to stop axle wrap, and extend the driveshaft. How high can the rear blocks be on a stock 99 Yukon before having to 1) add shims, 2) extend driveshaft, 3) add leafs to stop axle wrap.
Does any of that have to be done on 2" blocks? What about 3"?
 

h0tr0d

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I got under there today and the torsion keys are cranked with a 1/4" thread showing.

Will the crossmember-drop lift give me 1 more inch?

The crossmember drops start at 4" I think, so you'd have a net gain of at least 2" if you de-cranked your keys. The plus side of it is that you'd have a much better ride and less stress on your cv half shafts. The down side of it is price...They start at about $1k and if you have auto-trac you'll need a new front driveshaft which runs about $450.

I might be wrong on that, maybe someone else will chime in.
 

bowtiefreak

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To answer a few questions here:

99gmc: if your keys are cranked just about all the way, chances are that is the max lift you will get on an OBS. Our stock keys are enough to crank to the droop stops. If you need more lift ytou need a real lift at this point, something like a 6" kit with no crank, which on mant kits is about 4". You you have a picture of the front suspension of your truck you can post (picture from the front of the truck so we can see CV angles and so on).

99yuk: axle shims are used for a few reasons, you are starting to get into the realm of needing to research U joint phasing. A quick summary is that on a standard driveshaft the angle on the upper U joint must match the lower angle, if the lower angle is different you get vibrations. So typically you should not use a shim UNLESS you have a CV shaft. In that case you need your pinion angle to match with in a degree or two the angle of the driveshaft. Trust me it gets to be a pain in the ass but my advice is no shim.

mdiacont322: do not reuse U bolts they stretch and the old bolts will come loose on you...trust me. Buy new bolts. I bought from truckspring.com in Michigan, I bought a 5/8" bolt that is grade 8 and much stronger than the shit you find in pepboys and autozone for example.
 

99GMC

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To answer a few questions here:

99gmc: if your keys are cranked just about all the way, chances are that is the max lift you will get on an OBS. Our stock keys are enough to crank to the droop stops. If you need more lift ytou need a real lift at this point, something like a 6" kit with no crank, which on mant kits is about 4". You you have a picture of the front suspension of your truck you can post (picture from the front of the truck so we can see CV angles and so on).


I ended up going with a ReadyLift torsion key leveling kit giving me 38" in the front with room to go another 1" or so but I'm gonna keep it the way it sits for now. I had to get it aligned again but it still rides likes factory. Here a pic:
 

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bowtiefreak

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Sounds like your bars are worn. Our stock keys shold be enough to crank to the stops. If you need more lift, that would be the route I'd look into. Different keys are indewxed differently allowing more crank, which in your case helped make up for worn bars
 

1BADI5

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Crank the keys while the truck is on the ground right?
 

1BADI5

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I read and seen conflicting reports here

Crank the key while the truck is on the ground or with the front wheels off the ground.

My area of expertise in truck suspension has been lowering them for the last 15 years...... so lifts are generally new to me.

Any advice will be appreciated.

LASTLY: are the OEM Bilsteins fine with a 2/2 lift? or do I need to look into shocks with longer travel?
 

1BADI5

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Weekend bump!!!!!!!!

I looking to buy shock soon any intel would be great
 

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