83 K10. 6" lift. Question

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83customdeluxe

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I installed a 6in lift. My drive line angles are terrible since I didn't shim my axles. What degree of shims would I need? & should I drop the transfer case as well? I was told I could destroy my transmission if I don't. This is my daily driver, I just drive a few blocks a day no crazy off roading
 

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Strick

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The rear block kit should have a pinion wedge made into it. You may could get a 4 degree shim and add to the spring pack but the obvious problem is the necessity of lengthening the rear driveshaft. The way the yoke is pulled out of the transfer case tail housing I'd suspect it would be no time before either the rear bearing in the case or the yoke itself to break. There are companies that make a spacer for the front shaft IF you are having the same issues there as well.
I usually take the spacer from the crossmember bolts and sandwich between the frame and crossmember as a means to drop the unit about 3/4 inch or so. Be mindful about the engine fan hitting the shroud when doing this though. I've had trucks that I had to "adjust" at the radiator because the trans/case unit was dropped.

HS
 

83customdeluxe

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So I can just buy blocks that are already shimmed? Sounds easier than trying to wedge one in. I don't even like the blocks but I didn't have $800 to spend on already lifted rear springs. Think I'll save for that after I get my clutch replaced. What is the company name that makes the spacers? How would I lengthen my drive line? I'm not sure where the cross member is & I'd rather not drop the transfer case. I definitely don't wanna break anything so I'll probably stop driving it till I fix the issue with the **** hanging out, I added a pic of the front drive line to the post
 

Bextreme04

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I installed a 6in lift. My drive line angles are terrible since I didn't shim my axles. What degree of shims would I need? & should I drop the transfer case as well? I was told I could destroy my transmission if I don't. This is my daily driver, I just drive a few blocks a day no crazy off roading
You lifted it with blocks, so you never changed the driveline angles. If you drop the T-case, you will be changing the angle of the transfercase drive side and would then need to shim the rear axle. Basically, if you extend a straight line out from the transfer case and a straight line out from the front of the pinion on the axle, the two lines should be parallel. The problem you are going to run into with a big lift with very little driveshaft length, is that the angle needed is going to be very large. You want to keep the operating angles at 3 degrees or less, but that is almost impossible on a lifted truck. Heres a calculator tool that spicer has. It also has driveshaft diagrams and tables showing operating angles and good guidance on what you should be looking for. You can get an angle finder from amazon or harbor freight to plug in the values for the calculator.

https://spicerparts.com/calculators/driveline-operating-angle-calculator#more
 

Bextreme04

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The big problem you have is that the slip yoke is not inside the T-case enough anymore. It is unsupported and is flopping around against the bushing. It will wear it out and eventually snap your tailhousing off the T-case. Thats why you see all that fluid thrown around near the t-case tailhousing. You can just get your current driveshaft extended at any driveshaft or offroading shop. It's pretty common. General rule of thumb for most driveshaft lengths is to measure the distance is to have the rear axle at the fully compressed height, then disconnect the current shaft from the axle, bottom the slip yoke out in the tailshaft, then pull it out another 1/2-1". Once it is bottomed out and then pulled back out that 1/2"-1", measure how much longer it needs to be to fit back in the axle. Tell the driveline shop to extend it that much and rebalance... done.
 

83customdeluxe

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Damn. I shouldn't have lifted my truck. That sounds expensive & I would have to get my truck hauled over an hour to get to a drive line shop. If I sold this truck as is what do you think I could get for it? I definitely should have got pre lifted springs
 

Bextreme04

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Damn. I shouldn't have lifted my truck. That sounds expensive & I would have to get my truck hauled over an hour to get to a drive line shop. If I sold this truck as is what do you think I could get for it? I definitely should have got pre lifted springs
I think you are still misunderstanding something here...

Lifting it with a spring might actually have been worse. Using a block in the rear means that the driveline orientation did not change at all. Had the lift springs changed the geometry, and you still lifted it the same amount, you would have needed to use wedges or drop the transfer case in order to get them back in alignment. Then, you still would have to have solved the problem of the 6" lift making your driveline be too short.

Different springs or moving the spring mounting points will change the geometry. The height of the lift makes the distance the driveshaft needs to be increase. Generally, a 4" lift is considered the absolute biggest lift you can go without needing to lengthen the driveshaft.
 

Craig 85

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I can't tell too much in the front, but it seems your front spring are short for some reason. The shackles look pulled forward instead of being close to vertical. Could just be optics.

You could always get a shorter block in the rear with a taper to lower it and in the front take out a leaf or two depending how many are in there. It may get you down to a 4" lift, but would be a lot less headaches.
 

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