Drive Shaft Vibrations Solved Step-by-Step

cant buy, gotta make one. and the 4runner driveshaft is for the 4wd (ask me how i know... i purchased it then was mega disappointed)

i took it in to have the 4runner cardon cut off and put on my axle, they wanted more to do that because of the extra work.. and who knows the condition of the cardon being that its used, possible rebuild ontop of all of that.

so i got a quote, 500$ + tax + random BS to have the cardon added. f-it i said. this truck is turning into a PITA and now that i've got the rear main leaking on a motor with 40k on it.. this might be the end.

 

alright guys i gave up. i've installed up to 25 washers over between 0 and 2 inches in ever combination, up side down, downside up and there isnt a magical spot.

this is me running up the white flag. tomorrow afternoon i am going to a local driveshaft shop and talk with them about a 2 piece with a double cardon (aka "cv" ) on the back of the 1st half.

DONE.

i've wasted more money in gas/bolts/washers not to mention all the cussing and my time.... should have cut to the point to begin with.

 

Prerunner right seric? Please keep me updated. I'm right there with you and when I finish my lift after tax returns ill be heading to a driveline shop too.

 

wow apparently the places in arizona want upwards of 600 to MODIFY a driveshaft Augh. thats nearly double what i expected to modify.... Last place I called told me they built a CV Driveshaft and it DIDNT solve the guy's vibes (2012) ..



Anyone out there have any known connections ?

 

My input on the prerunners: there's only a few of them around me that I could crawl under and measure the angles, along with a couple of modified used trucks on the local dealer lot, and it seems all the lifted prerunners have their rear pinions set angled UP and pretty close to matching the angle of the rear half drive shaft (pinion points in-line with rear drive shaft half and directly at carrier bearing), then they have a fatty aluminum block for a carrier bearing spacer, usually between 1inch and 2inches. Seems kind of whacked to me, but that's consistent from six different trucks. My very first fix for my 4x4 was to do the same thing, tilt the rear pinion up to match the rear shaft, and then tweak the carrier bearing drop. I only changed it because of potential long term problems with those u-joints, but vibes were pretty close to gone.

Update on my truck: installed a 42gallon custom gas tank where the stock tank used to be, which forced me to abandon my carrier bearing spacers due to clearance issues between the drivelines and the new fuel tank. So off to a local driveline shop to get a one-piece driveshaft, only to find out a one-piece would also be too large around for my limited clearance, so..... $900 later I'm driving a custom two-piece double cardon drive shaft, silky smooth but expensive. Mine has the double cardon joint after the carrier bearing, which is back in it's stock position (no spacers), and the rear driveshaft has the slip joint down by the rear pinion (instead of up by the carrier bearing like the stock shafts have). Not ideal, puts that slip joint down in the mud more often, but I'll lube it with every 5k oil change and cross my fingers. And I didn't change my rear leaf shims so I'm still running about 0.5deg down angle on the rear pinion (driveline shop said to align rear pinion with rear shaft, which got me thinking about all those prerunners I looked at, same alignment). Seems that even with bad alignment, a double cardon just sucks up any vibe issues. More moving parts, but a potential solution.

I've got the only double cardon driveshaft I've seen, and again, it was only due to clearance issues caused by the new fuel tank (600mile range). Mine was built completely new from all new parts as I couldn't afford the down time with my daily driver 4x4, thus the larger expense.

 

so if im on the same page as you and i think i am, prerunners are pointing pinions at carrier bearing and dropping between 1-2 inches?

is so thats what i've been doing. augh. looks like a few more test drives are in order... time to go lower.

edit, i lied... im already at 6.9 degree's on the 1st shaft from tranny... next step i think is to flip carrier bearing and try that... start from scratch

 

Ok so i was doing some interesting reading about True Universal Joint Operating Angle

http://www2.dana.com/pdf/J3311-1-DSSP.pdf

good info... CONSIDERING OUR DRIVESHAFTS AREN'T STRAIGHT! i dont know how i missed it... see page 11... then crawl under you truck.. put your head under the tranny and stare at the pinion... all the sudden bam.. you see it.

-- <- pinion
\
|
-- <- tranny

this makes sense why measuring and putting it into alignment with what should work dosen't. now its not much but its there!

 

I've noticed that as well. Well, you guys have shed some new light on this and I can't wait to get back to work. I'll try pointing my pinion up and then messing with the cb. Any ideas on what angle to point my pinion up or what shims to use? I'm using a 1" block in the rear.

 

For now forget the angles. Just point the pinion up-ish, and drop the carrier bearing down-ish. I never saw any perfect alignment, the angles were all over the place on the prerunners I looked at. Confusing as hell, but OPPOSITE to what I've been advising for 4x4's, (uh....... sorry 'bout that Bacon.....). My bad for total lack of prerunner experience.

Oh hey, by the way those leaf shims are stack-able, by design. The little ridges keep them from sliding apart, so feel free to just loosen the axle u-bolts slightly and slide shims in and out till things improve. I also found that you don't have to get too wild crazy about retorquing those u-bolts for a MILD test drive, just remember to get them back to torque at the end of the day (easy to get frustrated and bail to the couch without torquing, just ask me how I found that little issue out......).

 

im at 3 degree's and in know its gotta be close.. going to realign the 1st shaft to 1-1.5 degree out of the tranny and re-measure.

i can taste victory..... wonder if off-setting the carrier bearing would have any effect? much.. much more difficult... last resort i'd say.

 

i'd be willing to bet that 4wd is more in line with the pinion now.. curious if you wana crawl under there and check?

 

Don't sweat it tscot. It's all trial and error and as far as I'm concerned you've already gone above and beyond for me and for that I am grateful. I'm sure I'll get it down soon and have some good results to post to help others.

 

Stopped carrying my angle finder, bag of washers, and socket set around with me (shocker, I know) so i can't measure angles, but I crawled under my 4x4 and a co-worker's prerunner here in the yard and snapped a few photos. The red lines are mostly in-line with each shaft, just to give an idea of how things are aligned.

The PreRunCB measures exactly 1" on that aluminum CB drop block. Looks to my eye that it pushes it down too far, but my co-worker reports zero vibes. Not a clue how that setup works, crazy looking to me.

And if you want crazy, notice on my whacked out double cardon setup that absolutely nothing is lined up with anything. I just unbolted the old driveshaft and bolted up the new one without changing anything from my perfectly shimmed and CB dropped setup I spent soooooo long messing with (well, removed the CB drop block but that's it). Crazy thing is smooth as silk due to all those joints moving around, but I know I still need to raise the rear pinion to line it up like the prerunner setup. For me it will be a simple matter of flipping my leaf shims around, from fat wedge in front (pushing front down) to fat wedge in rear (pushing rear down & thus front up).

 

that angle off the tranny looks nasty, any idea what its at?

 

little update, flipped carrier bearing... up.. is clearly not the answer, back down we go...

 

subd

 

update - nothing works. changing out rear transmission mount since bad and seeing what effect that has. i've flipped the carrier and shimmed up to 18 washers (1 inch) and flipped back to normal and tried 1-18 washers and its the same stupid vibe just at diffrent frequencies. flipped was the worst and anything over 14 washers just introduces a 21mph shudder.

 

You're gonna have to try all those combinations again with different shims on the axle. Frustrating I know.

 

so below is what my angles look like now with a 1.5" CB Drop.

i know im going crazy because i swear the steering is getting heavier the lower i go on the CB... or im trying WAYYY to hard to feel shit that isnt ther.

 

This may be a dumb question...but im new, and what the hell eh. My truck is lifted about 2.5". no CB drop, axle shims. and no vibes. but ive recently noticed a high pitched squeel in the rear which only happens when coasting without power to the wheels, and sounds like bearing squeel. My question is, even if there are no vibes, are there things that need to be done to set proper angels to all the joints to ensure proper operation and longevity? I keep reading people doing these things ONLY when a vibe develops, but seems to me that after changing all those angles with a lift, these things need to be reset? or am i wrong in this. cheers