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EIEIO
10-28-2004, 09:46 PM
I called Tom the other day and he informed me what resources to use to make a mount. So I replaced them all and now I get a harmonic in cab in between 40-50km/h that is almost defening. And now at about 90km/h I get a whistle that is very high pitch (not a whine, its like having bad airflow somewhere and its whistling off that, but x200%).

I did tighten the mounts all the way till you really couldnt anymore, should I back them off a bit so they are a bit more loose? Any help would be great, its my daily driver and its gonna make my mind go numb.

My rig is smaller than yours!!

Going diesel power

sj-x 500
10-28-2004, 09:56 PM
you... didn't unphase the d-shafts ... did you?

zuk: being prepared for total tear down. yota's 5.29's arb's.
ford: it drives.

EIEIO
10-29-2004, 03:07 AM
do you mean did I get bigger sized busihings and move everything up a bit?? I made sure I got the same size spacing as a stock t-case mount. Checked all my u-joints while I was under incase something happened when they all tore and they are fine. I just may have tightened them down to far so that there is no vertical movement, just like chucking a couple of bolts in there, I think I tightened them to as fas as the nuts could tighten (no more threads left). When I get home im gonna try loosening them all up to see if the harmonics change pitch, if so I may just have to play with how much torque is on the bolts.

My rig is smaller than yours!!

Going diesel power

STranger
10-29-2004, 03:58 AM
anothr thing to consider is if the hole that the bolt goes through is big enough to clear the bolt-it should be at least 5/8" for the bushing to seat properly.these mounts are stiffer than stock,so if you have t-case issues they will transfer more noise to the truck.

i dont need people to get me,i just need people to get out of my way

EIEIO
10-29-2004, 05:47 AM
I used the same size bolt of the stocker and the mounts fit the bolt snug. I dont believe I have any other t-case issues, that I know of, but could have had some cause I think one of the mounts has been ripped since I got the rig. I will try and loosen up the bolts and see if that has any difference. Just got 45 minutes left here at work before I can go home... FINALLY!! I do expect louder than normal as the sound disperses (sp?) throughout the frame, but not to the point that it is. I almost dont wanna sit in the rig when it hits that note. Its in the 100+db range.

My rig is smaller than yours!!

Going diesel power

STranger
10-29-2004, 06:41 AM
ouch-something is an ugly issue if its that loud!

i dont need people to get me,i just need people to get out of my way

sj-x 500
10-29-2004, 06:56 AM
are the drive lines *i'm thinkin the one from the tranny to the t-case* still in phase? do the yokes line up properly?

]====[

look like that

zuk: being prepared for total tear down. yota's 5.29's arb's.
ford: it drives.

EIEIO
10-29-2004, 07:50 AM
everything looks ok, i will have another look at it in about 30 minutes when I make my way down. And when you say in phase, you mean everything looks straight right?? Its only between 40-50km/h thats why I dont think any of my main stuff is broken, anywhere else it feels stronger than ever, its like everything hits perfect harmonics. But I do notice now that when I brought it home I can minimize the sound or make it louder depending how much foot I put into it.

My rig is smaller than yours!!

Going diesel power

EIEIO
10-29-2004, 08:27 AM
Just went and checked it out, loosened the bolts a bit for a little more play to the actual mount. Checked out the intermidiate shaft and it shifts a bit if you rotate it but back and forth or side to side is fine. Now by in phase you probably mean some word that I have no clue what you are talking about. If in phase means by the angle of it, I was thinking that after I looked at some of the Rocky Road/other 4x4 companies mounts, it shows the same setup though they have it place as bolt, lock washer, frame, bushing, t-case bracket, bushing, nut, nut.

I have similar but it goes bolt, lock washer, frame, bushing, bushing, t-case bracket, nut, nut. Maybe the extra bushing inbetween the t-case bracket and the frame maybe be pushing it up 1/2 inch or so. I will run down and swap them around to see if it makes a difference.

Took it out for a spin and it is a bit quieter, not much though, now its between 40-45km/h. But still hits close to 100db.

My rig is smaller than yours!!

Going diesel power

StinkFinger
10-29-2004, 08:51 AM
IN phase refers to the drive shaft yokes they should be in line with each other hence the little diagram

]========[



at any other angle it will cause vibration a rokie mistake is to opse them at 90 or just not being aware and randomly placing them with no regard for phase

jeep, because my wife made me
Quote of the week:
Dear diary jack pot gigity gigity(the family guy)
thats not food thats what food eats (red forman)

EIEIO
10-29-2004, 09:46 AM
nope, shes not straight, complete angle. Should it be straight?

My rig is smaller than yours!!

Going diesel power

StinkFinger
10-29-2004, 09:52 AM
Yes they should be directly in line with each other

jeep, because my wife made me
Quote of the week:
Dear diary jack pot gigity gigity(the family guy)
thats not food thats what food eats (red forman)

EIEIO
10-29-2004, 11:39 AM
that prolly would be the problem, its on about a 10 degree to 20 degree angle.

My rig is smaller than yours!!

Going diesel power

Dakguy
10-29-2004, 02:46 PM
Dude you missin' it. The ears of the two ujoints should be aligned. If you look down the length of the shaft you should only see two, not four 'tabs'. HTH...

Of all my friends, I like beer the best!

EIEIO
10-29-2004, 03:31 PM
Im kinda confused by what you are talking about Dakguy. So I decided to take some pictures and noticed some intresting things.

http://www.bczukis.com/Shaft/DSCF0002.JPG

Here is a shot of the intermidiate shaft.

http://www.bczukis.com/Shaft/DSCF0003.JPG

tranny side of the u-joint

http://www.bczukis.com/Shaft/DSCF0004.JPG

t-case side

http://www.bczukis.com/Shaft/DSCF0005.JPG

one of the bushings after I reversed it around only having one in the middle, noticed that now it is just sitting on the frame, no bushing really inbetween it.

http://www.bczukis.com/Shaft/DSCF0006.JPG

Thats the front d-shaft, it looks REALLY close to the t-case bracket.




From those pictures it looks like everything is sitting to low in my mind. I took the bushings and matched them up so they were the same thickness as the OEM rubber bushings. That was with 2 in between they were the same size. Any recomendations?

My rig is smaller than yours!!

Going diesel power

StinkFinger
10-29-2004, 03:48 PM
your stupid give me a call maby i can come look at it

jeep, because my wife made me
Quote of the week:
Dear diary jack pot gigity gigity(the family guy)
thats not food thats what food eats (red forman)

EIEIO
10-29-2004, 08:36 PM
ROFL!! just a little bit =P Its about 10:30 right now and I am at work. I think I have started to reduce the noise a little bit, started to make sure the angle of the t-case ujoint looks parallel to the transmission u-join by lowering and raising certain mounts. I have gotten it down to a very quick medium buzz.

Hey and dont make fun of my dissabilities...





.. ok its to easy to.

My rig is smaller than yours!!

Going diesel power

westcoaster
10-29-2004, 08:45 PM
I looked at your picture and compared it to my samurai, lying flat on your back looking up at your rear mount you should have the frame mount, 1 3/16" "spacer" and the tcase arm. The mounts I have here are completly isolated between the bolts (read all rubber with no hardware connecting the bolts)

EIEIO
10-29-2004, 08:49 PM
ayh dem stocker mounts, they are all rubber, the ones I have are a bolt all the way through, im not paying $20 a fucking mount to have it break on me the next weekend. I would rather keep adjusting to figure it out. I think I almost have it anyways, its pretty smooth now, just a little more fine tweaking.

My rig is smaller than yours!!

Going diesel power

westcoaster
10-29-2004, 09:07 PM
yup, but the point is, they are 1 3/16" thick..... looking at your photo there, you had yours squished all the way down on the frame. No wonder your front drive looked like it was going to hit..........

edited to add: find something that is roughly that thick and your clearance problems would be solved and any possable vibration due to the t case being mounted at the incorrect height.
any other vibration would be attributed to haveing a solid bolt instead of a rubber isolated mount.

westcoaster
10-29-2004, 09:17 PM
Then again if you were REALLY good, you could fab up something that would use chain or cable to prevent the stock mounts from streaching so much they break.....

EIEIO
10-30-2004, 04:14 AM
Just after I took those pictures I took the mount on the bottom and put it in the middle to equal the same size as the OEM mounts. I have it down to just a little rattle at 40km/h. And I noticed I can change the pitch of the u-joint on the t-case by tightening and loosening certain mounts to suck the case up or down. Thus it has made alot less noise by adjusting it and trying to get everything in line. I will fine tune it a bit more today and should get rid of all the NASTY vibrations.

After I took those photos I realized that all the brackets and shit was just lying on the frame and the bushings were doing shit all. Also the front d-shaft was about 1cm away from the t-case bracket.



Overall I find this kinda neat, with just doing cars before I had no idea about any of this kinda stuff, and I appreciate what everyone has told me, I know I dont know much about it, but hey this is how we all learn right [36]

My rig is smaller than yours!!

Going diesel power

Dakguy
10-30-2004, 11:39 AM
Sounds like you've pretty much got it covered. For future reference, if you removed the shaft the circled 'ear' on the ujoint should be on the floor along with the one at the other end of the shaft. If you were to take your shaft apart and put it back together a spline or two off the 'ears' would be out of phase and you will get vib problems. In order for the shaft to be balanced they must line up, HTH...

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Of all my friends, I like beer the best!