vibration after u joint replacement

Discuss anything related to drivetrain problems here (Engine, Transmission, etc)

Moderator: Staff

vibration after u joint replacement

Postby SSM200 » Sun Jan 31, 2010 9:57 pm

I changed my U joints a while back and ever since, it sounds and feels like i'm driving over gravel and vibrates. Doesn't matter which gear or in neutral. Starts at 45 mph and continues till about 65. Probably still there, just less noticeable because of the increased frequency of the vibration. I replaced the u joints again and it still does it. It is worse the heavier load i'm carrying. and feels like a back massage to the rear passengers. I wonder if it is just a coincidence that it started when I changed the u joints. It also does it with the back on jack stands in the driveway at the same speed.

Steve
94 Amigo 2wd calmini tube bumper---Custom diamond plate skid plate---Calmini add-a-leaf---
calmini header 2 1/4" free flow exhaust---rebuilt motor with delta 270 cam---Custom diamond plate cladding
ImageImage
User avatar
SSM200
Trail Master
 
Posts: 652
Joined: Tue Mar 11, 2008 7:20 pm
Location: st. louis
Has thanked: 0 time
Have thanks: 0 time

Sponsor
 

Postby Tanman85 » Mon Feb 01, 2010 4:36 am

Sounds like your driveshaft isn't balanced anymore after you did the u-joints.
This can happen if you don't mark the flanges before disassembly and then use those marks to put it back together. Did you remove the whole driveshaft when you did the work? Try disconnecting it at both ends again and rotating it 180 degrees and re-installing.
-Mike
95 Trooper 3.2 SOHC Auto 200K, Spectre/DIY air intake, K&N air filter, front and rear poly sway bar bushings, 255/70/R16 Definity Dakota A/Ts, Magnaflow cat, Flowmaster 50 series, 2.5" exhaust, removed factory exhaust restrictors, Superwinch hubs, fuel injectors serviced by RC Engineering, PCV catch can, SS brake lines, JET Performance ECU, Hayden electric fan, B&M trans cooler
Tanman85
Has a Trail Truck
 
Posts: 332
Joined: Mon Mar 31, 2008 10:19 am
Location: Milwaukee, WI
Has thanked: 0 time
Have thanks: 0 time

Postby SSM200 » Mon Feb 01, 2010 8:32 am

I tried that too. the new u joints have zerk fittings and the old didn't. does that make a diff? maybe i just need it balanced. I marked the shaft but not well enough and it wore off before i was done :oops:
Steve
94 Amigo 2wd calmini tube bumper---Custom diamond plate skid plate---Calmini add-a-leaf---
calmini header 2 1/4" free flow exhaust---rebuilt motor with delta 270 cam---Custom diamond plate cladding
ImageImage
User avatar
SSM200
Trail Master
 
Posts: 652
Joined: Tue Mar 11, 2008 7:20 pm
Location: st. louis
Has thanked: 0 time
Have thanks: 0 time

Postby SurferJoe » Mon Feb 01, 2010 11:34 am

I seriously doubt you modified the balance enough to make it vibrate with the zerked version of the u-joints.

More than likely you got the shaft(s) out of phase and they are in the wrong position. Turning 180º is not gonna do anything but re-emphasize the problem.

Either that or you don't have one of the cups in the "home" position and it is making the d-shaft run non-concentrically.

Let me get a pix of PROPERLY timed driveshaft u-joints for you ...brb

OK --- this is the correct position to keep the u-joint phase in sync

Image
Joe Vreeland - In The Bitterroot Valley, Montana
User avatar
SurferJoe
I am the Stig
 
Posts: 4432
Joined: Thu Jul 24, 2008 10:44 pm
Location: SW Montana, in the Bitterroot Valley
Has thanked: 8 times
Have thanks: 11 times

Postby SSM200 » Mon Feb 01, 2010 5:57 pm

I have a one piece drive shaft. here are some detailed pics.

Image

Image

Image

the isuzu service manual is sorta pointing toward a bearing of some sort. But i was hoping it was simpler.

Steve
94 Amigo 2wd calmini tube bumper---Custom diamond plate skid plate---Calmini add-a-leaf---
calmini header 2 1/4" free flow exhaust---rebuilt motor with delta 270 cam---Custom diamond plate cladding
ImageImage
User avatar
SSM200
Trail Master
 
Posts: 652
Joined: Tue Mar 11, 2008 7:20 pm
Location: st. louis
Has thanked: 0 time
Have thanks: 0 time

Postby Airhead rider » Mon Feb 01, 2010 6:37 pm

Can't say for certain the protruding caps are incorrect but can say I've not seen any like that. I'm also in the middle of changing both u-joints on the front shaft of my Trooper and have changed a bunch over the years.
91 Trooper LS 3.1 tranplant, 5 speed
94 Trooper
91 Trooper 2.6 5-speed
Airhead rider
Almost Joe Isuzu
 
Posts: 2897
Joined: Fri Feb 20, 2009 1:09 am
Location: Iowa
Has thanked: 1 time
Have thanks: 27 times

Postby SurferJoe » Mon Feb 01, 2010 9:55 pm

Aha! It looks like some of the needle bearings fell over and kept the trunnion from getting to center on the shaft.

You prolly ruined a few needles and if so - do NOT be tempted to just take them out and throw them away because there are "so many of them" that missing a few won't hurt!

It will - hurt that is.

In days past when I did this for a living, I always took the caps off the trunnions and using a grease gun I just filled the caps totally to keep the needle bearings in place whilst I put the d-shaft back together with a hammer.

I had a boss who always just watched me dumbstruck - as I merrily hammered the d-shaft back together with --- a hammer (what else?).

He always stopped to watch when I did u-joints and said that when he only just walks past a new u-joint still in the box and he's carrying a hammer, he could hear the bearings fall out!
Joe Vreeland - In The Bitterroot Valley, Montana
User avatar
SurferJoe
I am the Stig
 
Posts: 4432
Joined: Thu Jul 24, 2008 10:44 pm
Location: SW Montana, in the Bitterroot Valley
Has thanked: 8 times
Have thanks: 11 times

Postby Airhead rider » Mon Feb 01, 2010 10:08 pm

Had the same thought too Joe but twice and both times on opposing caps?
Shouldn't these caps also have the circlips on the inside? If so, and you couldn't get the caps on far enough to put on the clips...
You might also check how the yoke fits in to the rear of the tranny. Most have a bushing in the tailstock to limit slop.
91 Trooper LS 3.1 tranplant, 5 speed
94 Trooper
91 Trooper 2.6 5-speed
Airhead rider
Almost Joe Isuzu
 
Posts: 2897
Joined: Fri Feb 20, 2009 1:09 am
Location: Iowa
Has thanked: 1 time
Have thanks: 27 times

Postby SSM200 » Mon Feb 01, 2010 10:50 pm

Airheadrider and Joe
Yeah I thought it was the needle bearings too, but i was extremely careful about this, as I've had one fall over before, and it was the second install in about a month. On these u joints, no you can't get the clips on with a needle out of place. about the bushing, what would this do? do you think the bushing is missing or something? When i pull the drive shaft, gear oil comes out where it meets the tranny. is this normal? why would gear oil be there? someone must have put it there because the only place i know gear oil to be is in the rear end.
94 Amigo 2wd calmini tube bumper---Custom diamond plate skid plate---Calmini add-a-leaf---
calmini header 2 1/4" free flow exhaust---rebuilt motor with delta 270 cam---Custom diamond plate cladding
ImageImage
User avatar
SSM200
Trail Master
 
Posts: 652
Joined: Tue Mar 11, 2008 7:20 pm
Location: st. louis
Has thanked: 0 time
Have thanks: 0 time

Postby SurferJoe » Mon Feb 01, 2010 11:09 pm

Ya know - it COULD be the wrong trunnion too! Ford trucks have a dual-dimension u-joint and it can drive a mechanic crazy that way.

Any time a circlip (inside OR outside) cannot be installed SOMETHING'S WRONG.


As for the tailshaft bushing - yes, if you pull the slip splines out - there is oil!

The bushing itself should NOT allow very much up-down or side-to-side movement at all. A little is good - but it becomes a feel-thing so if you have no hands on experience with it you may misinterpret what you feel as bad and it isn't.

Suffice it to say that IF the rear seal can handle the movement - then the bushing's prolly close to OK too.

Back to the problem-at-hand though ----- you've got to get that off-centered u-joint problem dixed or you WILL blow a rear bushing or tailshaft or transmission case or you'll pole vault the back of your Isuzu after the driveshaft beats the undercarriage to death spinning around uncontrolled and loose like a crazed steel water weenie.
Joe Vreeland - In The Bitterroot Valley, Montana
User avatar
SurferJoe
I am the Stig
 
Posts: 4432
Joined: Thu Jul 24, 2008 10:44 pm
Location: SW Montana, in the Bitterroot Valley
Has thanked: 8 times
Have thanks: 11 times

Postby SSM200 » Tue Feb 02, 2010 12:32 am

:shock: I can see it now... the amigo's first front flip. i gotta fix this. like now
94 Amigo 2wd calmini tube bumper---Custom diamond plate skid plate---Calmini add-a-leaf---
calmini header 2 1/4" free flow exhaust---rebuilt motor with delta 270 cam---Custom diamond plate cladding
ImageImage
User avatar
SSM200
Trail Master
 
Posts: 652
Joined: Tue Mar 11, 2008 7:20 pm
Location: st. louis
Has thanked: 0 time
Have thanks: 0 time

Postby Airhead rider » Tue Feb 02, 2010 1:09 am

On most, maybe not all driveshafts you will see where it has a tab spot welded on it for balance. Suppose it is possible it has disappeared and the shaft is no longer balanced. Not saying that's the case, just see if there might be an area towards one end that looks as though something was once there. I really don't know how bad it would vibrate minus this weight (if in fact it had one now missing), just throwing it out there.
91 Trooper LS 3.1 tranplant, 5 speed
94 Trooper
91 Trooper 2.6 5-speed
Airhead rider
Almost Joe Isuzu
 
Posts: 2897
Joined: Fri Feb 20, 2009 1:09 am
Location: Iowa
Has thanked: 1 time
Have thanks: 27 times

Postby Airhead rider » Tue Feb 02, 2010 2:58 am

One last thought, you said it also vibrated with the wheels off the ground and on jackstands. Did you happen to remove the rear wheels and check for vibration?
91 Trooper LS 3.1 tranplant, 5 speed
94 Trooper
91 Trooper 2.6 5-speed
Airhead rider
Almost Joe Isuzu
 
Posts: 2897
Joined: Fri Feb 20, 2009 1:09 am
Location: Iowa
Has thanked: 1 time
Have thanks: 27 times

Postby SSM200 » Tue Feb 02, 2010 5:36 pm

no i didn't remove the wheels, but got new tires since then and i am sure they do a dynamic balance on them and any wheel or tire issue would red flag real quick. all weights still in tact.

The manual troubleshooting section for rear axle (no troubleshooting for drive shaft) vibration points to either worn rear hub bearing or bent rear axle shaft. I doubt axle shaft, because i think i would have to have damaged it, not worn it out.

???
94 Amigo 2wd calmini tube bumper---Custom diamond plate skid plate---Calmini add-a-leaf---
calmini header 2 1/4" free flow exhaust---rebuilt motor with delta 270 cam---Custom diamond plate cladding
ImageImage
User avatar
SSM200
Trail Master
 
Posts: 652
Joined: Tue Mar 11, 2008 7:20 pm
Location: st. louis
Has thanked: 0 time
Have thanks: 0 time

Postby Airhead rider » Tue Feb 02, 2010 11:54 pm

Not possible someone else smacked a curb or are you it's only driver?
I'd think if you rigged up a jack stand (or something) and had a dowel, coat hanger, or something firmly attached coming off it horizontally and had this pointer moved right up to the wheel, but not touching it. With that wheel raised slightly and rotate the wheel by hand I would think you should be able to detect any run out, such as bent wheel, bent hub, etc.
Similiar to a motorcycle or bicycle wheel trueing stand.
If you have a magnetic base and indicator all the better but you get the picture.
91 Trooper LS 3.1 tranplant, 5 speed
94 Trooper
91 Trooper 2.6 5-speed
Airhead rider
Almost Joe Isuzu
 
Posts: 2897
Joined: Fri Feb 20, 2009 1:09 am
Location: Iowa
Has thanked: 1 time
Have thanks: 27 times

Postby Airhead rider » Wed Feb 03, 2010 1:13 am

Not knowing for certain if the vibration started after the new tires or if it was pre-existing I'll throw out a couple more thoughts. I'm going to assume just new tires, not new wheels too.
First, I agree on the wheel bearing not being the problem though anythings possible. My experience is a wheel bearing will make some ugly noises as it fails.
Grasping at straws, I'd also consider moving the rear wheels to the front and see if the vibration moves too. I'd at least consider getting the balance checked again too. Doubt everyone agrees with me, but I mount my own tires and often don't balance them until I've put a few miles on them. I've seen it on cars, but more often on my motorcycles. If I balance a new tire then check it after about 1,000 miles it will need rebalanced. After that second balance it will stay balanced.
Years ago I had an auto-mechanics teacher tell me the same thing. Tires setting on a rack for some time will change after they have been ran a while.
Lastly, don't rule out tread seperation even on a new tire, unless of course the vibration was there even prior to the new tires.
91 Trooper LS 3.1 tranplant, 5 speed
94 Trooper
91 Trooper 2.6 5-speed
Airhead rider
Almost Joe Isuzu
 
Posts: 2897
Joined: Fri Feb 20, 2009 1:09 am
Location: Iowa
Has thanked: 1 time
Have thanks: 27 times

Postby SurferJoe » Thu Feb 04, 2010 10:17 pm

I just got back from a 1200 miles road trip and my front u-joint started to vibrate - and get this - at EXACTLY 45 (indicated) MPH to about 62 (indicated) MPH.

Falling back on your reason for the question/post -
Post subject: vibration after u joint replacement


The vibration is NOT more obvious in any gear - it is purely a road-speed and therefor driveshaft RPM thing.

Tires in the 15-inch category are known to start hopping at about 52-56 MPH depending upon the ultimate size and how far out of balance they are -but if they are dynamically out of balance, they usually also exhibit a "wobble" or shimmy in the steering if they are in front or they can blur the interior mirror or shake the door mirrors when they come in and out of phase.

I'm opting for the d-shaft here as your vibration, again restating what I find obvious:
Post subject: vibration after u joint replacement
.

Bent axles are all possible as are failing bearings too - but they make noise at times when they don't shake or wobble too. Usually axles don't spontaneously bend either.

If you have a manual transmission, just hang your hand on the gearshift when you sense the vibration. I bet you can feel it strongly there.

And - finally - I think this is kinda indicative:
Post subject: vibration after u joint replacement
Joe Vreeland - In The Bitterroot Valley, Montana
User avatar
SurferJoe
I am the Stig
 
Posts: 4432
Joined: Thu Jul 24, 2008 10:44 pm
Location: SW Montana, in the Bitterroot Valley
Has thanked: 8 times
Have thanks: 11 times

Postby Airhead rider » Thu Feb 04, 2010 11:36 pm

Yup, yup...I reread the original post. I thought the u-joints had been changed twice trying to eliminate a vibration, not that the vibration started after a u-joint change. I'll have to pay more attention.
Think I read another post where ssm200 now has the engine out of it so vibration I'd assume is no longer the primary concern.
91 Trooper LS 3.1 tranplant, 5 speed
94 Trooper
91 Trooper 2.6 5-speed
Airhead rider
Almost Joe Isuzu
 
Posts: 2897
Joined: Fri Feb 20, 2009 1:09 am
Location: Iowa
Has thanked: 1 time
Have thanks: 27 times

Postby SSM200 » Fri Feb 05, 2010 5:40 pm

vibration is a priority, as is the motor, which i just got back in. i want to fix the vibration problem before i get it back on the road. trying to bowl a strike with this project if you know what i mean. Yes i feel it strongly on the shifter. I guess i'll pay to have it balanced. same price to check it as to balance it. I am still confused as to how replacing the u joints caused this. or maybe new ones made it more noticeable since the old ones were bad (clicking). Thanks for the help everyone

Steve
94 Amigo 2wd calmini tube bumper---Custom diamond plate skid plate---Calmini add-a-leaf---
calmini header 2 1/4" free flow exhaust---rebuilt motor with delta 270 cam---Custom diamond plate cladding
ImageImage
User avatar
SSM200
Trail Master
 
Posts: 652
Joined: Tue Mar 11, 2008 7:20 pm
Location: st. louis
Has thanked: 0 time
Have thanks: 0 time

Postby SurferJoe » Wed Feb 17, 2010 11:08 pm

OK - it's been a few days now - is there any news yet?

A-hem!
Joe Vreeland - In The Bitterroot Valley, Montana
User avatar
SurferJoe
I am the Stig
 
Posts: 4432
Joined: Thu Jul 24, 2008 10:44 pm
Location: SW Montana, in the Bitterroot Valley
Has thanked: 8 times
Have thanks: 11 times

Postby SSM200 » Mon Feb 22, 2010 8:48 pm

hey surfer joe it was drive shaft out of balance. weird because i didn't lose any weights. new thread- DIY drive shaft balance

Thanks everyone for the help!
94 Amigo 2wd calmini tube bumper---Custom diamond plate skid plate---Calmini add-a-leaf---
calmini header 2 1/4" free flow exhaust---rebuilt motor with delta 270 cam---Custom diamond plate cladding
ImageImage
User avatar
SSM200
Trail Master
 
Posts: 652
Joined: Tue Mar 11, 2008 7:20 pm
Location: st. louis
Has thanked: 0 time
Have thanks: 0 time


Return to Drivetrain Problems

Who is online

Users browsing this forum: 96TrooperSE and 1 guest