Vibrations: Observations,Conclusions etc...

So a little background, I have a 2012 DCSB it has been vibrating since day one. Once I put a lift on it the vibes obviously got worse, here is a link to my first fix. So if you haven’t read that or been keeping up on the vibe issues I suggest you read it to catch up on what I have done.

http://www.tacomaworld.com/forum/2nd-gen-tacomas/208402-finally-fixed-my-vibes.html

So if you took the time to read the link welcome back if not keep reading.
I wanted to start a new thread because I have a lot more info on what I have done and what I think the problem is. So to start this off, the one piece drive shaft worked well but it doesn’t work if you have a long bed I have a short bed but I wanted a fix for everybody, plus I think I will have problems later on with the CV joint wearing out prematurely with the shaft being so long, that is a lot of weight for that CV joint, plus someone mentioned there might be clearance issues with a one piece (think it was Maxamillion2345). I actually checked the clearance issue by attaching the trailer I occasionally use for work and sure enough it was pretty tight, tight enough that I decided to put a little more money into some R&D to come up with another fix.
So once again Max had mentioned that the Tundra used a two piece driveshaft with a carrier bearing but it had a CV joint after the carrier bearing, so I thought that might be worth exploring. Off to the junkyard I go, I find a DS out of a 2000 Tundra with a V8 and sure enough it has everything I am looking for. Take it home to take some measurements and it is almost a direct bolt in very cool, so I take it down to the driveline shop to have it shortened by 2” and they say no can do it is a crimped together driveline and they cannot modify it DAMN!!! so close. Back to the boneyard the guy at the junkyard actually suggested I look at a first gen Tacoma because he thought they had the same set up but it was a welded shaft. He was correct so I took that home and took some measurements and found out that the front part with the carrier bearing had to be shortened and the last half had to be lengthened no big deal took it down to the drive line shop and had the wizards down there make it up for me. So I paid $60 for the drive shaft at pick-a-part and $175 to have the driveline shop modify it for me all in all not that much more to do it this way and the long bed trucks will be able to use this fix also.
Ok this is where it gets interesting, I installed the new shaft and took it for a test drive the good news is the 20mph vibe was gone, the bad news is the take off shudder was back. Ok what the hell? Get down on my creeper and look things over notice the angle at the transfer case side was maybe to much so I get my angle finder out and sure enough it is 2.5 degrees between the DS and the transfer case this angle needs to be under 1 degree from what I understand. So the only way you can get that angle to change is to lower the transfer case. I was just about to give up and put the one piece back in but decided to at least take out the t-case mount and see if it could be modified, after looking it over I decided to take a shot at modifying it. Here is what I did, I took out the mount not that hard maybe 15min to pull it out, then I put it in a vise and widened it out a little bit and then notched the bolt holes so it would sit a little lower in the cradle. Well that cured my takeoff shudder.
So some observations and conclusions looks like the 20mph vibe is associated with the u-joint behind the carrier bearing and the takeoff shudder is from the transfer case angle being off. Which brings up the question what does Toyota do when they put in a different t-case mount I have the sneaking suspicion that they rework that mount so the t-case sits lower which makes sense, just wondering why some have vibes and some don’t maybe they have two different manufacturers of that mount? I would love to build some data on the clearances of the mount though, I wasn’t thinking of it at the time but I should have measured the before clearance on the t-case and the after to see how much I was able to drop it. Right now it is sitting at 2 - 1/8 from the bottom of the t-case to the top of the frame. I was wondering if anybody would be willing to take measurements on that particular point so we can get a data base built and maybe come up with something conclusive. If you take that measurement be sure to put down if you have a vibe or don’t and if you had the TSB mount put in, that way we can get a clearer picture of what is happening. I probably only lowered it about 3/8 to ½ inch but it was enough to bring that angle down to about 1 degree.
I have some pics posted to show a little bit of what I did.
1st pic: New driveline with the CV joint behind the CB
2nd pic: Transfer case angle that needed modified I circled it in yellow.
3rd pic: How I notched the t-case mount.
4th pic: Where I measured the t-case to frame.
One more thing if you use a 1st gen DS you will still need to drill the rear flange to accept the smaller bolt pattern. There is probably going to be some questions I will try to answer them as best I can but I will be in and out of anyplace I can get online for a couple of days so don’t think I am ignoring anybody and I would really appreciate it if we could get some measurements from people on that t-case mount.

 

Wow nobody is interested? Could someone with vibes please measure the t-case mount and somebody without vibes measure also, would be greatly interested to see if there is any difference.

 

good you posted in the other thread I'm going to check out that mount and reply. I bet there'd be more posts if it was warmer weather right now.

 

i mentioned this in a couple of threads. I've lifted a lot of trucks in my day and i can recognize a pinion angle vibe a mile away.....this shudder feels JUST like a pinion angle issue from the get go.

I got under there and inspected all the angles around the drivetrain and it seemed like they were all over the place but pretty much within spec. However, god knows I've had pinion issues when even off by 2 degrees in the past and I've had to get rid of even that 2 deg issue to loose bad vibes. there are lots of 2+ deg all over this drivetrain, i just didn't go far enough into isolating which.....basically because by then i was pretty pissed that i was under a 2012 truck that has been in production for 7 years and with just 500 miles measuring pinion angles because its fucking shuddering on two gears.

 

drsus I hear ya pisses me off a brand new truck does this and they say its "normal" I isolated the problem and now need more data to come up with a consensus about the t-case mount would be nice to have some ammo to fire at the dealers and toyota.

 

I put on toytec 3" coilover and add-a-leaf in the rear with bilstein 5100s all around on my '11 trd sport this weekend. I have a take off shudder and vibration. I'm currently running stock wheels and tires. I'm willing to take some measurements if I knew exactly what I needed to measure. Someone clarify all that I need to measure and I'm willing to help gather data.

 

If you look at the picture with the tape I measured the bottom of the transmission to the top of the frame where the mount sits, I lowered the back of the transmission but since I didn't measure the before distance I don't know how far I was able to drop it. So if you could measure from the bottom of the transmission to the top of the frame we could see how far I was able to drop it by modifying my mount. Have you tried to shim the CB any or flip it around that might also relieve some of the symptoms. Only takes a few minutes to try that I think there is a couple of write ups floating around for that but I am pretty sure it is the angle at the transmission side that is causing the take off shudder.

 

Love my truck since new in '06. HOWEVER, I want my take-off shudder gone! Here's my question about lowering the transfer case's rear mounting bracket: By lowering the rear portion of the transfer case, what kind of funkiness/leverage will that cause where the transfer case mates to the transmission? If the aft end is lowered down, won't the front end (where it joins to the transmission) have to be raised equally?

 

It doesn't matter what other peoples measurements are. Just set up your rig according to basic driveline mechanics.

U-joints like to work at the same angle. Buy a digital angle finder. Measure your t-case output shaft angle then measure your pinion shaft angle on your rear axle. they should be the same or less than 1 degree off. Buy the correct shims as needed.

Both axes of the drive shaft need to be the same. Measure both and adjust the carrier bearing with shims till it is exact.

Make sure your U-bolts are torqued to 75-90 ft/lbs

 

Okay. I dug up the 15-25 mph vibration TSB (T-SB-0132-08) and found the part #s for everything involved (my truck is out of the 5 yr/60K mile powertrain warranty due to age, so I have to do the TSB myself). It appears that the updated rear transmission/transfer case mount that Toyota uses in this TSB is lowered, but I won't actually know until it arrives and I can compare it to the original. Before pulling the trigger on a $250 locally manufactured 1-piece driveshaft (using my stock driveshaft for parts) or a $500 Tom Woods 1-piece driveshaft, I thought I'd give this a try. I'll be out about $94 including shipping, but what the heck. This essentially accomplishes what the OP did by modifying/lowering the rear transmission mount. Hopefully this will cure my take-off shudder. Parts required FOR A 4WD V6 are:

1. 12371-31250: Insulator, Engine Mounting, RR
2. 90201-10033: Washer Plate, 6.5mm (two required)
3. 91671-80820: Bolt w/ Washer, 20mm (two required)
4. 91671-B0816: Bolt w/ Washer, 15mm (four required)

It's going to be several weeks because the mount is back-ordered, but I will update once it's installed.

 

Sub'd for results ^^^

 

X2 I honestly thought nothing of it until reading this thread linked off one about the 2012 doing it, Mine started after my 3inch lift a year ago. I just got so used to it over time and now I thinking I will do this if it fixes it.

 

Has anybody made sure the U-bolts are torqued properly on the 2012's?

 

Interesting on that TSB mount I was wondering if they lowered it or not. The best fix is still the one piece driveline the one I modified out of a 99 4runner is still doing the trick. I put it back in and took out the two piece because the vibe wasn't all the way gone and with the one piece it is I think with a little more time and effort I would have gotten the two piece vibe free but I am out of time and its summer so heck with it maybe this winter when the weather turns I might mess around with it some more.

 

If you have takeoff shudder under 10mph, it is almost always due to carrier bearing placement and is typically easily solved with $10 of home depot hardware and a ratchet...



Gnarly takeoff shudder to silky smooth in about 2 minutes...

 

You don't understand the joy of reading this thread. As above I installed a TW one piece to 'ridd of the shudders after a modest lift, but always felt uneasy when towing the trailer or bouncing around back roads with the center support an inch away for the drive-shaft. One question: I take it as the the flanges of 1st gen and 2nd gen are the same? no other mods (other than what the shop did) are needed? I like the double cordon joint but no dive-shaft shop here ballsy enough to tackle the mod of installing a D. cordon to my stock shaft sitting in the garage...

cheers

 

OP, did you put the DC joint at the t-case and make the pinion parallel with the shaft? That final u-joint needs an operating angle of about .3* or nearly 0*. Even with a severe angle at the t-case you're splitting the angle with a DC. So if that angle is roughly 5* you're u-joint operating angles are going to be 2.5 and 2.5. That shouldn't be an issue there.

 

I installed the new TSB rear transmission mount today. I've only driven it 9 miles since, but first impressions are that it helped reduce the take-off shudder - but not eliminate it altogether. If the shutter was a 5 before, a quick guess based on my limited driving is that it's now a 2-2.5. Measuring from the top of the frame's cross member to the bottom of the transmission: 2-9/16" before and 2-3/8" after. So, the mount did lower the rear of the transmission 3/16". I haven't measured the angle of the output flange to compare before/after, but I will soon. I'll also post pictures in a day or two and give further post-installation eval (busy). I just wanted to get this info out because I know some folks are interested.

 

sub to get rid of my vibes

 

Max,
Yes I put the DC at the T-case unfortunately I didn't measure the angles after I was done because it totally got rid of the vibes so I left it alone. I no longer have my truck due to some medical issues, I had to downsize for a while so I can't get those angles for you but for me that single piece cured everything.
Hilux30,
The first gen DS needs the rear flange drilled and needs to be a bit longer on the back side after the carrier bearing and a little shorter before the carrier bearing no big deal for a good driveline shop but the one piece out of a 4Runner is still the easiest way to go with the best results.