so i just put a 6.5 inch iron rock long arm in my jeep put new ujoints in both front driveshaft and axle shafts for some reason in 4 wheel low i get a chunking sound from the middle of the jeep have no clue what it is anyone have an idea?

 

your front pinion angle is wrong you need 7 degrees of positive caster on the front. do u have a sye kit in the rear or a tanny drop?

 

also is this on dry pavement? only 4 low? might be binding on the ground. t-case drop or sye?

 

i did the hackntap and have a front shaft in the rear when i pull the front shaft out and only have the rear shaft its ok, the iron rock kit has adjustable caster for the pinion is the pinion going up positve and the pinion going down neg? thanks guys

 

the pinion should be pretty level relative to the ground. the angle the castor refers to is at the knuckle. and again, its only in 4 low? and it never did it before in 4 low? does the wheel being straight or turned affect it at all?
by the way with that much lift you never get that kind of castor, 5-5.5 should be good. but either way you shouldnt have that kind of problem.
now does it do it as soon as you start moving or do you hae to build any speed?

 

yes 4 low I think it did it in 4 high as well ill have to try it again. never did it before wheels being straight or not doesn't matter does it both building up speed it does it and only seems to do it when accelerating and engine braking coasting doesn't do it

 

sounds like the front shaft is binding than. how do the joint angles look? try to tilt the pinion up some with the adjuster and see if it goes away.

 

ok ill give it a try tomorrow wish i could stick my head down there and look lol maybe put it up on jack stands and try it will see thanks

 

im almost positive its a caster issue. positive caster is towards the cab negative caster is towards the headlights your looking for 7 degrees of positive caster. this would cuase binding of your front drive shaft there could also be a problem with the front axle not disengaging.

 

going to buy an angle gauge today to make sure i set it right, how do i know the front axle isnt disengaging? and how would i fix that

 

ok i bought angle gauge and put it on my drive shaft and tried to adjust the pinion but the angle on the gauge didnt even move. i took some pictures to see if yall see something wrong. also it seems to chunk more when turning in 4low then going just straight but does it both and does it in 4hi as well

 

also another thing the crossmember has built in holes for a transfercase drop and its set at a 1 inch drop even tho i have the hack n tap in now could that cause it?

 

ok put the crossmember up to get rid of the transfer case drop that did nothing on a side note i did notice that when i push on the ujoints at the transfercase there is some play like the little center ball in the yoke is loose i did replace the ujoints but didnt do anything with the center ball over then repack it with grease

 

ur pinion is kinda high nut dosent look to far off suck your upper control arms in by a half inch mine on my rustys long arms are at 15 1/4 give or take a few mm. put that transfer case drop back in

 

also check your cv joints on both your DS they should be tight