Hypoid

Hey-

'90 extracab, 3.slow

I've had BJ spacers and 1" front diff lowering spacers for a while now, no prob.

I fabricated and installed a 2" drivetrain lift. I drove it around in front wheel drive for a couple days or so until I fabbed a new rear driveshaft. I was getting a nasty front driveshaft vibration (I'm pretty sure). So I clearanced the CV like you see on the 4x4wire webpage that takes 5 min to load.

I still have this nasty vibration/banging/clanking noise that sounds like the front driveshaft. I get it in 4wd, or in 2wd with the hubs locked.

I know I need to get it on jackstands to see what it is, but it's that time of year when I try not to work on the truck. I also know that a CV driveshaft should have the pinion pointed at the transfer case, which is definitely not the case, but was also definitely not the case stock, or with the 1" drop spacers to keep the front axle CVs from binding.

So, the question is, who else has tried this combination; drivetrain lift + front diff lowering? Any issues? Think it might be something else?


Thanks

Jack

dropzone

iTrader: (6)

this link is what you used: http://www.4x4wire.com/toyota/tech/cvmod ?

is it possible you clearanced one side a little more than the other?
Did you get all the needle bearings installed correctly? Replace or should replace the u-joint?
Are your front CV's operating at a different angle now that if they were worn the new angle would complicate the issue?
Just throwing out some ideas. Hope you find the issue....

tc

You sure its not a bad CV axle that you just hear/notice now since you're in FWD? I have had to drive the truck that way a couple times, and it does drive strange.

I have always wondered why a CV driveshaft for the front too...

But my bigger question/concern is - I don't get it ... why do you need a diff drop with BJ spacers? Unless you have the crap torqued out of the tbars, that shouldn't be enough lift to worry about it.

So you did a DT lift to gain ground clearance, but your diff is still lower than stock? Even at 3" difference though, you're still less than the bracket lift guys with 4"-6" difference...

What size tire are you running? Other mods? Assume you have a BL too ...

Hypoid

Thanks guys.

To keep this from getting too confusing for terminology, I'm going to say double cardan for the driveshaft and CV only for the front axles.

That is the link I used to clearance the double cardan joint. I didn't realize clearancing one side more than the other could be an issue. I did clearance more than they show in their picture.

I may need to replace the u joints, but they felt fine in the DS out of the truck.

The diff drop/bj spacers/cv joints- When I installed the BJ spacers, at full droop I had CV binding. This has nothing to do with cranking torsion bars. Full droop is set by the bumpstops. I fabricated and stuck in 4crawler style diff drop spacers, and that stopped the CV binding.
I ran this setup fine, and the drivetrain lift left the front diff in the same place (it's bolted to the frame), same for the IFS control arms/CVs. I don't expect to see any change between the front diff and the CVs.

Yes, I do have a 2" DT lift with the rear of the front diff lower than stock. I didn't think of comparing this to the IFS bracket lifts. Do those rotate the diff?

I'm running 35" BFG ATs (measure around 33"). There is a 2" bl as well, wasn't too interested in cutting up my floor.

Aside from that, rear AAL and new shocks up front for the BJ spacers, very mild, really.

Thanks for the questions/ideas.

As soon as the weather's decent I'll pull the front DS and run around with the hubs locked and see how that goes.

Hypoid

Took a really long time to get to with the cold and snow we've had and no garage to work in. Truck handles like garbage in snow in 2wd.



Update:

20 year old ujoint clips were probably bent. When I finally got under there, I was missing three bearing caps. Took a few trips to the parts store to get the right ujoints. Seems to be working fine now.