8" lift, what degree shims for front axle?

Posted By: Brad4406

8" lift, what degree shims for front axle? - 06/09/14 04:54 AM

Has anybody installed an 8" lift on their 4X4s? If so, any idea what degree shims I need to purchase?

The last owner never hooked up the front drive shaft since, according to him, it has way too much pinion angle as the axle was never properly shimmed. I want to get this thing set up now before winter gets here and I'm found unprepared.

I know how to measure for pinion angle, as I have done it on a couple cars I've built, but I have no idea what the angle should even be for a 4X4.

Any advice would be appreciated, even if it's to dump the shim idea as it will seriously effect the front alignment and steering. Maybe I need to just spend the money for a double cardan shaft. I should probably look at the shaft I already have tomorrow as I may get lucky and it's already a double cardan.

Attached picture 8170167-IMG_20140418_191525_209compressed.jpg

Attached picture 8170167-IMG_20140418_191525_209compressed.jpg

Posted By: 340SHORTY

Re: 8" lift, what degree shims for front axle? - 06/09/14 05:36 AM

That much shimming is very bad. The amount need to correct the pinion angle is going to make the truck undriveable. You need to cut the inner Cs off the axle tubes, rotate the axle and weld the Cs back on at the correct caster/camber position...

Posted By: buildanother

Re: 8" lift, what degree shims for front axle? - 06/09/14 06:04 AM

I always wondered how these things would drive down the road with caster all out of whack after shim wedge placement on front axles.

Posted By: Joshs68

Re: 8" lift, what degree shims for front axle? - 06/09/14 06:26 AM

What about a double cardan (sp) front driveshaft?

Posted By: 340SHORTY

Re: 8" lift, what degree shims for front axle? - 06/09/14 07:13 AM

even with the double cardan the driveshaft would be running in an "S" I believe. Take it to an axle shop and do it right.

Posted By: viperblue72

Re: 8" lift, what degree shims for front axle? - 06/09/14 10:44 AM

Do NOT run shims. It will steer like he11 and pull all over the road. And you don't gain much by doing it.
As long as you lengthen the driveshaft and clearance the cv so the driveshaft can articulate at the angle, it should work okay.
Dropping the engine and xfer case down is an option too.

Posted By: 76dodgeboy

Re: 8" lift, what degree shims for front axle? - 06/09/14 03:20 PM

High angle Driveshaft. You DON'T shim the front because the steering.

Posted By: Brad4406

Re: 8" lift, what degree shims for front axle? - 06/16/14 12:08 AM

All,

Thank you for all the inputs.

340SHORTY,

I'll definitely do your suggestion on cutting, rotating, and welding the axle, but I'm going to wait until I get a 60 for it instead of wasting money and effort on a 44. Thanks.

Posted By: EV2RUNNER

Re: 8" lift, what degree shims for front axle? - 06/23/14 04:50 PM

Heres a trick if you don't Mind running Brand X Parts on your truck A Stock Chevy front shaft, from Late 70's Early 80's will fit perfect in 74-93 Dodge with 8" lift. You just have to switch out front yoke with GM Unit.I have done this on my 92 Gasser (Dana 44) and My 91 Diesel.(Dana 60) Both are lifted 8" (Well diesel is 6") But equal to 8" on gas truck.

Posted By: Brad4406

Re: 8" lift, what degree shims for front axle? - 06/29/14 05:45 AM

Quote:

Heres a trick if you don't Mind running Brand X Parts on your truck A Stock Chevy front shaft, from Late 70's Early 80's will fit perfect in 74-93 Dodge with 8" lift. You just have to switch out front yoke with GM Unit.I have done this on my 92 Gasser (Dana 44) and My 91 Diesel.(Dana 60) Both are lifted 8" (Well diesel is 6") But equal to 8" on gas truck.

Good info. Thanks. I'll go this route first, if I can find one.

Posted By: 340SHORTY

Re: 8" lift, what degree shims for front axle? - 06/29/14 07:53 AM

Quote:

Heres a trick if you don't Mind running Brand X Parts on your truck A Stock Chevy front shaft, from Late 70's Early 80's will fit perfect in 74-93 Dodge with 8" lift. You just have to switch out front yoke with GM Unit.I have done this on my 92 Gasser (Dana 44) and My 91 Diesel.(Dana 60) Both are lifted 8" (Well diesel is 6") But equal to 8" on gas truck.

Hows that gonna fix the bad angle? Other than the GM unit being longer, they both have CV yokes in them. CV yokes wont cure the problem..

Posted By: Mpetros

Re: 8" lift, what degree shims for front axle? - 06/29/14 11:11 PM

I would keep shimming it till the drive shaft doesn't bind and turn freely..What ever angle deg that it takes have steel angle shims made and cut and rotate steering knuckles on housing that same deg to keep steering geometry the same.. there has to be someone in your area that does that..In My Shop We charge $400.00 to cut and turn knuckles with housing out of vehicle just to give you some Idea on whats it cost.

www.Greensburgmachine.com

Posted By: WO23Coronet

Re: 8" lift, what degree shims for front axle? - 06/30/14 04:53 PM

I've never understood this, if you tilt/angle the front diff up, won't it throw your u joints out of phase? Not sure if that's the correct term but what I mean is don't both u joints have to be at the same angle (relative to the output shaft on the t case and input on the diff) for it to operate smoothly and not vibrate? Or do you use the CV type in conjunction with an angled diff so it doesn't vibrate?

Posted By: Mpetros

Re: 8" lift, what degree shims for front axle? - 07/01/14 03:08 AM

Quote:

I've never understood this, if you tilt/angle the front diff up, won't it throw your u joints out of phase? Not sure if that's the correct term but what I mean is don't both u joints have to be at the same angle (relative to the output shaft on the t case and input on the diff) for it to operate smoothly and not vibrate? Or do you use the CV type in conjunction with an angled diff so it doesn't vibrate?

You are 100% Correct.. But on a lifted Truck tilting the axle is the lessor of the 2 Evils.. Drive Shaft holds up better because its lessening the Joint angle..And a Cv Joint on one end

www.GreensburgMachine.com

Posted By: EV2RUNNER

Re: 8" lift, what degree shims for front axle? - 07/04/14 06:46 AM

Quote:

Quote:

Heres a trick if you don't Mind running Brand X Parts on your truck A Stock Chevy front shaft, from Late 70's Early 80's will fit perfect in 74-93 Dodge with 8" lift. You just have to switch out front yoke with GM Unit.I have done this on my 92 Gasser (Dana 44) and My 91 Diesel.(Dana 60) Both are lifted 8" (Well diesel is 6") But equal to 8" on gas truck.

Hows that gonna fix the bad angle? Other than the GM unit being longer, they both have CV yokes in them. CV yokes wont cure the problem..

Ive never had a problem with angles on either one of my trucks, and one was beat hard off road.. Maybe I got lucky I dunno?

Posted By: CTD5.9

Re: 8" lift, what degree shims for front axle? - 07/04/14 04:16 PM

Quote:

Ive never had a problem with angles on either one of my trucks, and one was beat hard off road.. Maybe I got lucky I dunno?

I think there is always some over dramatic tendancies regarding axle angles and driveshafts. Sometimes it's very hard to achieve the ideal angles, the joints will live but not for the full livespan that they should.

In my offroad only truck I have shimmed for an 8" lift, it isn't undriveable. The driveshaft is still at an ugly angle, had to grind all the little tabs off the CV but it still takes 500HP blasts through the mud pit.