Angle on two-piece drive shaft?

[mthompson]

I'm pretty sure I know the answer...but I want to make sure.

My new-to-me truck has a 6" BDS lift. I've been under it a lot lately flushing things, spraying undercoating, etc. I noticed that the 2-piec drive shaft is not even close to straight; that's what caught my eye. I thought to myself "how can that work properly like that?" I know there is probably a slight tolerance on the angle at the carrier bearing, but mine is probably a 7-8° angle off of straight.



Should this be more or less in direct line? That's what I would think at least. I do have a slight vibration at 2-5 mph, but that is about it. And it is more pronounced if I am turning during that first bit of acceleration.

I think I am going to do the washer shim experiments and then make a solid spacer when I find the right position. Any other suggestions?

Also, is that the factory carrier bearing bracket? I bought the truck with the lift, so I don't know the stock configuration.

Thanks,

MT

[KPBJJ]

You need carrier bearing shims. I heard you want 1/4" drop for every 1" of lift. Mine had vibration at low speeds and completely went away when I shimed it. You can use bar stock and just drill two holes in it. My 6" revtek lift came with two shims each about 3/4" thick. You want your drive shaft as straight as you can get it.

[mthompson]

Were your shims angled at all? I dropped it using 3/8" washers to see how far I would need to go.probably need a little more, I am running out of threads on the bolts and the hanger looks like it needs to angle forward a bit in order to the sit a 90° with the drive shaft.

Might look for asecond commercial shim kit.....

[KPBJJ]

My shims don't angle. The carrier bearing can pivot in the housing. Mine came with longer bolts too. Get 3/4" bar stock and longer bolts.

[KPBJJ]

I have seen aftermarket brackets for sale also. But I think shimming it is gonna work just as good and be a lot cheaper.

[04blackcrewcab]

I hear its like 1/4" worth of shims for every 1" of lift. Or something like that.

[KPBJJ]

Yep. 1/4" for every 1" of lift. Should make it nice and straight.

[mthompson]

Ok, thanks guys!

I'm definitely in need of longer bolts. I 8 1/8" washers on each side now, and it still has a bit of vibration and the drive axle is visibly crooked. I'll have to go to 1.5" I think for my 6" lift. I suppose I need to measure my lift too....bought it lifted and I'm not sure how high it is. I thought 6", but I was looking at that "lifted 6.4L" thread and I'm not sure if it's 6" or 8"....

Do you think stainless bolts will work or should I just get the nickle plated? It's not much difference in price for two bolts. And can I just use regular hardware bolts or do I need to locate some like the originals with a tapered tip?

Hopefully Fleet Farm has some bar stock as well....otherwise I'll have to search around for that as well.

Thanks,


MT

[mthompson]

I was thinking, since this is just a spacer for mounting the bracket lower, and not really a bracket that gets much force on it, especially impact.....could I make the spacers out of extruded plastic, HDPE actually? We have 1/2" HDPE sheets at work, similar to the density of a cutting board, but thicker. Sure would be a lot easier to cut and drill!!

specs: Sheet Stock, Corrosion Resistant, HDPE, Black Color, Thickness (Decimal) 0.500 In, Width 48 In, Length 96 In, Thickness Tolerance +/-0.025 In, Width Tolerance +/-0.125 In, Length Tolerance +/-0.125 In, Min Temp Rating -58 Deg F, Max Temp 194 F, Tensile Strength 4000 PSI, Impact Strength 1.3 Lbs, Standards FDA, USDA


Thoughts?

[mthompson]

I got my spacers made up this weekend.

Before:


after:


spacer:



I used two pieces of 1/8" aluminum to sandwich three 1/2" ish hdpe spacers and switched the bolts to 3" length.

I'll drive it for a while, but it seems to be where it needs to be.

Thanks,

MT