Just fixed driveline vibration!!!For free!

The way you take these measurements matters. There are certain relationships that have to be right. When you set the pinion angle (at the diff) equal to the TC output shaft you create 2 parallel lines. Then you bisect these lines with a nearly straight line created by the driveshafts. This geometry creates cancelling angles at both ends.

It is true that you can create the cancelling joints in other ways. You can drop the CB way down till the operating angle at the diff is essentially zero. Since the pinion and the TC are usually in alignment, this creates cancelling angles in Joint 1 and 2. The problem is that it also creates a large operating angle at the TC which will shorten the life of that Ujoint, and may limit it's operation at higher speeds. The steeper a Ujoint operates, the lower it's maximum speed. In a stock truck it is already at 5 degrees operating angle. I don't know where it would end up with the drop needed to create this geometry. In addition, this will only work if your pinion angle and TC are in fact matched. If not, you are right back where you started from.

 

Just lifted my 2011 DC. Three in front , two in back. CB dropOME, Front diff drop. Vibes at highway speeds. Gonna try the CB flip this week, with and without drop. See what works best before I fry my brain with all these measurements and math. Sounds like that is the nut shell trial and error method. Great info guys!!!!!!!

 

All my lift products came from Toytec by the way. Great stuff!!!!

 

I put the same lift on my 06 access cab, had the same vibrations.. This whole time i thought it was coming from the front diff. Guess I have been looking in the wrong place for the vibe.. Chalked up the vibes on the 06 to a worn output bearing in the front diff, traded the truck(like my DC better anyway). I know that is not the case with this new 2011 with the same vibes, bearings are not out. This is all very interesting, was gonna see if Bryan Easler Toyota in NC was going to stand behing thier Lifetime powertrain warranty they gave me with this new truck. They sell Toytec kits at that dealership, installed or not, and said Toytec would not void thier warranty. Would not buy one without it becuase of the crappy front diffs.

 

This would explain why the BeefedTaco CB drop of 1.5" or 2.25" works for most people. I agree that it increases the angle on the TC u joint to a point that concerns me. At the same time you get an opposing angle on the CB and you reduce the angle on the pinion to near zero. In theory that should and does work. I'm going to try that temporarily with some long bolts and temporary blocks to get the CB down 1-1.5" and then measure the angles and drive it and see if that gets rid of the take off shutter. Even it it does I dont think I'll leave it like that. I dont think I would be comfortable with those large angles. The take off shutter is really not that bad just a little annoying and I get no other vibes (I've had it to 90 mph). Except the front vibe / grind but I've gotten used to that too! But thats another issue all together.

keep us posted on that! After you have them lift it I'd love to see how toyota deals with the issues.

 

I lifted both trucks myself. They assured me I would not matter who performed the work as far as the warranty goes. Gonna try fixing it my self first, and wait for something to wear out to see what they say

 

Yes, that is why/how the beefy works. Drawbacks are increased TC operating angle and reduced driveline clearance for offroad use. That's why I prefer the other method. If your temporary shims work and you decide to do that, I would get the Beefy unit because it is more stable.

 

Here are the three possibilies:
1. (my preferred method and Toyota's method) Align the TC output shaft and pinion shaft to be parallel. On most trucks with well designed lifts they will already be correct. Then drop the CB a small amount until the two driveshafts almost form a straight line (less that 1 degree). This geometry puts the 1st and 3rd joints canceling. Joint 2 is (near) zero. Side effects = none.

2. (Beefy CB drop) Align the TC output shaft and pinion shaft to be parallel. On most trucks with well designed lifts they will already be correct. Then drop the CB until the rear shaft forms a (near)zero operating angle with the pinion shaft. This geometry puts the 1st and 2nd joints canceling. Joint 3 is (near) zero. Side effects= greater operating angle at the TC joint will cause faster wear and may limit high speed operation. DL clearance is reduced.

3. (Spicer diagram) Raise the CB until the first shaft forms a near zero operating angle with the TC output. Adjust the pinion angle to be parallel with the first shaft. This geometry puts joints 2 and 3 canceling. Joint 1 is (near) zero. Side effect: Driveline clearance will be increased. A custom crossmember will be required to relocate the CB. Operating angles at Joints 2 and 3 will be increased causing accelerated wear and possible high speed limitations. This method is commonly used in trucks with long shafts and little lift where the angles are not a concern. Most commercial trucks are set up this way.

Note 1: Joints should never run at a dead zero operating angle. That's why I keep saying "near zero". A joint that operates at zero will not rotate on it's needle bearings and will wear in one spot on each post/cap. The bearing must operate at a slight angle to move lubricant and to wear evenly around the post/cap. Joints can, and should run at a zero relative angle when parallel axis are established.

Note 2: Toyota did not make any mistakes in the design of this drive shaft system. They chose option one for the same reason I chose it. They used a 2 piece shaft to eliminate critical speed instability, and they designed it for the least side effects. My only complaint, or perhaps question, is why they used such a wimpy carrier bearing. I don't know. I think some of the issues stem from that, and I plan to change that on my truck eventually. For mild lifts of 3" or less the geometry can pretty easily be returned to optimum by understanding the reasoning behind the geometry.

I think that's about all there is to say on the subject.

 

Well I just finished up getting longer bolts and thicker washers for my homemade CB drop. Ended up dropping it 13/16ths and my 2nd shaft is about .6* steeper than my 1st shaft. TC and Pinion are within ~.2* of eachother, and my driveline is NNIICCEE!! Thanks Badger for the help! Maybe one day I'll get around to someone fabbing me a 7/8" drop with 3/8" holes in it and I'll replace my 8 washer combo and get my shafts exactly at .5* of eachother like Badger recommends to keep the U-Joints lubed and operating correctly.

BTW, ended up using an M10 X 1.25 X 55MM bolt to give me some extra slop to play with for the new CB bolts. Unfortunately couldn't find "flanged" bolts the size I need, but I got plenty of double thickness Grade 8 washers that work essentially the same.

When you find one let me know, I'd probably be interested since It seems like and easy enough swap. Having got up there recently it sure doesn't seem very "beefy" so-to-speak.

 

Sweet! I just used a washer under my bolt head. After using washers to establish the thickness, I made real spacers from aluminum blocks.

Here's a way to make spacers from washers though:
1. Assemble the washers you need. I like to use washers with a close fit to the bolt and a large OD. Usually going down a size gets the fit right.
2. you'll need a dummy bolt (or 2) with a shank long enough for all the washers to stack on. You'll need nuts and a few extra washers too.
3. Spray the bolts, nuts, and extra washers with silicone or WD-40.
4. drop one lubed washer onto the bolt. Coat all the spacer washers with a thin layer of JB weld. It won't take much! Using too much just makes remoal harder. Stack all these washers onto the bolt followed by as many lubed washers as needed to cover the shank.
5. Snug down the nut and let it cure. Wipe off whatever squeezes out.
6. When it is cured, remove the nut and pop off the spacer.

It makes a pretty decent little spacer. Strong as hell. I've used this trick many times. You can clean off the oil and paint it too. It's much more stable than loose washers.

Edit: a comment about something you said a few posts back about All-Pro Springs: Mine and all the ones I've seen on other trucks did in fact maintain perfect pinion angle. It appears that AP's claims are accuarate and they did do their homework on this one. All they require is a little CB shimming and everything it good.

 

I like that idea bonding the washers. Questions: What are the actual angles you have at the TC and Pinion? How much lift are you running actually?

 

Turned my CB over and used the OME CB drop. Vibes gone all but at 43 to 48 MPH. Close enough to perfect for me I guess. Got to give a little to get a little. Thanks guys!!!!!

 

I have a vibe around 45-50mph and im pretty sure its tire balance issue. My take off shudder is almost gone, i think i need to lowere my cb alittle more to get my 2nd joint angle closer to 0. Right now its at about 1* or 1.5*.

 

I have 3.25" of lift I don't know what the actual angles of the TC or the pinion are because they don't matter. I zero on the TC and the pinion angle is within .1 degree of that measurement. The operating angle at the TC is 5 degrees and at the pinion it is 4.8. These are the angles that they makes with the driveshafts.

 

I thought I was starting to understand all this and it really doesn't sound like it should be so difficult.

I have a 19 degree difference between TC and rear diff....

I'm doing something wrong

 

Ok thats what I wanted to know. That clears it up for me. The difference is I'm only lifted 2" and have only 2.5 degrees at the pinion. The TC is the same at 5. I dont want more lift than what I got for now. I tried shimming the CB down about 1.25" but I still had the shutter and the angles were all F'd up. Not going that route. I'm thinking the axel shim 2-3 deg down should do the trick for me. It may be a while for that. Where can I get axel shims? Thanks

 

You can get axle shims through Toytec ^^^^

 

I would check with a local driveline or spring shop for the shims, mainly because Toytec doesn't have a complete selection. I believe Benz Springs in Portland Oregon carries shims. Betts Springs probably carries them too. I've seen them in the past from 1 degree on up.

 

Thanks Badger! My aal was giving me a take off shudder after I got rid of my shell. Followed your #1 example and it worked great! Downloaded an angle finder app for my Droid and went to work. Ended up needing just an 1/8 washer and nothing else to space down the cb and get my angles right. No more shudder

 

I'm getting confused with terminology I guess...

in method 1 you never measured the angle of of the rear diff as I see others do in many other guides. I guess where I'm really confused is should the TC and the rear diff be at the same angle? I have a 19degree difference (aided by the fact that I don't really know where to put the digital angle finder on either of these things).

here is where I place the angle finder to get a 19 degree difference: