mstep3

After doing some reading I know that after installing a 2 1/2 - 3" lift up front that you can get some vibration from the front drive shaft when you don't have CAD. I'm assuming that this is probably putting some wear on the front u-joints. My question is do any of you guys that have installed 2 to 3" lifts up front know what you can do to keep from wearing out the front u-joints? The front drive shaft gets a pretty bad vibration around 65 - 70mph. Do longer control arms help the problem any or does it not help with the angle of the drive shaft?

Thanks for any suggestions or help..

johnh

i don't know if the "newer" vehicles have them,but i had a '74 dodge that had a CV joint first out of the transfer case, then a regular u-joint.......... i don't remember ever replacing the front u-joint or CV joint as long as i had it

Hodge

On my 94, I have a double cardan u-joint at the transfercase, and then a regular joint at the axle.
I would imagine that with a lift, longer control arms will be needed to correct the angle. There are much higher lifts than 3", and they work, so it must be correctable.

Tate

Lock out hubs will get rid of wear on u-joints and unit bearings. Double win!

DIESELWRKS

are you sure your getting a front drive shaft vib driving? have you taken it off and driven the truck without the shaft. your lift isn't that much. I know on my 6" lift my shaft has play more on the slip/spine than anything due to it being extended out far.

mstep3

I'm pretty sure it's the driveshaft.....I only noticed the vibration after putting new coils in a couple of years ago....I put in the Carli Coils & 1" coil spacers....I can feel the vibration right under my feet around the u-joint right before it goes into the transfer case....I haven't tried taking it off to make sure, but I guess it would be a good idea....

mstep3

Is it a very big ordeal to take the front driveshaft out? I was thinking of removing it for a while to see how it drives.....

DIESELWRKS

nope have someone move your transfer case lever to gear then neutral as you turn the saft. then back in gear to loosen, etc. and break the bolts on the flange. take them off support the shaft with a strap etc. undo the u-joint straps. you can check and see if the u-joint on the end is bad if its good. put a wrap of tap going around end cap to end cap lika circle this will keep your caps on and clean. check your other joints on the shaft also.

mstep3

thanks for the help....i took a look at the drive shaft tonight....the u-joints look ok to me...they don't wiggle....the only thing that i'm not sure of is there seems to be some grease squeezing out around that rubber boot on the u-joints.....mostly around the u-joints at the transfer case end

i wanted to remove the drive shaft but i didn't realize there was a brace in the way below the transfer case.....i couldn't get any sockets or a wrench in there without having to remove it?

if i was going to go with some new control arms to try and correct the angle on the axle do you recommend going with the adjustable? do you recommend anyone who makes good adjustable control arms?

DIESELWRKS

use a wrench to get in there.
also when you checked the u-joint put make sure its not in gear and transfer case is in N, you can see the true play grabbing the yoke end and shaft end. I would not think the lift you have you would need diff control arms. as far as adjust arms DSS makes some they are built well but also need a built wallet$ when you do take the shaft off go ahead and remove the u-joint and check the tabs that it rest in on the yoke end make sure the yoke isnt' getting worn. a new joint is cheap to replace when you have the shaft out you can check the play on the double joint better and correct then when the shaft is installed. i just went through all that and ball joints axle joints hubs having a friend help and showing me alot of stuff to look for.

mstep3

thanks. you can turn the front drive shaft when the transfer case is in neutral even if the front tires are still on the ground?

i forgot about Solid Steel Ind. Those are nice control arms. a $1,000 is definitely a lot for adj. control arms.....The reason I was thinking about going with adjustable was because I would like to add another 1" or so of lift up front to level the truck.

DIESELWRKS

didn't see this earlier, if you disconnect the from u-joint from the yoke and keep it hanging up by a cord or someone holding it, with the transfer case in Neutral you can spin the shaft when you unbolt it.

mstep3

well....the front axle was definitely causing the vibration....after i removed it and got the truck up to 70mph, no more vibration.....it drives just a smooth as the day i bought it.....the u-joints all look good.....nothing is worn out or loose at all....

i think it must have to do with the angle of the axle after putting on the 3" of lift.....the vibration started immediately after putting the lift on....i'm hoping that some longer control arms might help it out.....

KATOOM

Well a couple things could be happening. Your driveshaft could simply be out of balance, the tabs on the double cardan could be touching just barely from the added angle, the u-joints and DC inner ball could be worn out, or the differential u-joint might be to far from 0*. When running a double cardan joint, the two u-joints inside the DC cancel themselves out which means that the differential u-joint angle cant be more than 0* (or close to it) otherwise there is no forth u-joint to offset it.

I suggest you make sure the tabs are not touching by turning it by hand while its mounted in place. If they are then you either need to change the pinion angle, drop the transfer case, or grind them down so they dont touch. Then remove it and take it to a reputable driveshaft shop and have them install quality non-greaseable u-joints and balance it.

Other than that, there's not much else to do but install part time hubs so you can unlock the driveshaft.

mstep3

well....i'm definitely not an expert on this stuff, but this is what i noticed when i was turning the drive shaft by hand with transfer case in N.....I was getting sort of a squeezing rubber sound...sort of like you hear when rubber is getting squeezed against something....it was coming from the double cardan joint....

when i took a look at one of the u-joints in the double cardan joint there was a little bit of plastic wearing off one of the sides of one of the plastic/rubber boots on the u-joint....i didn't think i should be hearing that sort of sound when turning it....also seems to be a lot of grease squeezing out of the rubber boots around the DC joint....

i do think you have it right with the pinion angle being too far off too....with my factory control arms the axle is tilted forward some.....that coupled with the increased angle of the drive shaft must be what is causing the problem......i'm thinking that i need to get some control arms that are made for at least a 3" lift & that might help....