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 havenít read that or been keeping up on the vibe issues I suggest you read it to catch up on what I have done.
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 doesnít 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 2Ē 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 donít maybe they have two different manufacturers of that mount? I would love to build some data on the clearances of the mount though, I wasnít 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 donít 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 Ĺ 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 donít think I am ignoring anybody and I would really appreciate it if we could get some measurements from people on that t-case mount.