Bad vibrations (1 Viewer)

[CruisinGA]

When my clutch pilot bearing bit the dust, it caused quite a shock to the drivetrain.
When I drove my 40 for the first time after getting the clutch repaired, there was a horrible vibration at nearly all speeds. Took the shaft off and found that the rearmost u-joint was bad in one axis of rotation. Replaced it last week, almost all the vibration is gone, all thats left is from a severly worn rear-end, thats getting replaced today.

 

[bad_religion_au]

how do you check that bad u joint on one axis, i only checked for slop, so may have missed it? please tell me CruisinGA

 

[CruisinGA]

Take the driveshaft loose from the rear 3rd member. (just a coupla 14mm bolts) and seperate the driveshaft at the slip yoke. (just pull on it). now wiggle the u-joint around and see if it catches in any directions. When rotating mine on one axis, it caught about 1/4 and 3/4 of the way through. Make sure its greased well. It should effortlessly "move around." While your at it, check the upper one as well, (still bolted to parking brake.) Mine had no slop at all, but one was still bad. They are simple to replace, just a beeeatch to get off when your replaced the original one from the factory 30 years ago. .
This is also the perfect opportunity to put them back "in phase."

 

[bad_religion_au]

thanks, i suspected that it may be time to pull it off. thanks for the advice, what type of grease should i grease them with?

i'm expecting to have to buy a new U joint because i figure it should be the problem.

hopefully i get time tomorrow to play, i'm swamped with assignments, why else would i be on ih8mud at 2 am?

 

[CruisinGA]

I put moly lithium base grease.
I think plain lithium is fine as well. (Thats what was in there when I pulled the u-joint from the box from SOR.)

 

[CruisinGA]

http://www.pirate4x4.com/tech/ujoint_install/
Thats the writeup I followed when I changed mine, I had never before changed a u-joint. I had to use my vise sometimes where he calles for some pliers, probably because my u-joint was practically welded in there from so much time.

 

[cruiserdan]

I blew through the posts on this so forgive me if somebody already mentioned this.

You could remove the rear driveshaft and take the vehicle for a drive on the front axle. If the vibration is gone something is probably wrong with the driveshaft. If the vibration remains the same, something else is wrong.

 

[bad_religion_au]

ok, i pulled the shaft, and checked it.

how much is catching enough to be a problem. it rotates fairly freely, i kind of sense a sticking on one axis, but doesn't feel enough. CDAN, i figured i'd try that idea when it stops raining.

the shaft was out of phase by 2 teeth, fixed that, and the vibration is slightly better, only seems to come on now when lugging in 3rd, or in 4th.

a couple of questions, is their any sensible reason my FRONT driveshaft would be out of phase just under 90 degrees, i put it back in phase while i was under there., but i'll put it back if it needs to be.

is the 3rd member the round disk thing coming out of the diff that the drive shaft bolts to with the 4 14mm bolts.

that disk seems to have a fair amount of slop. is this natural, or fixable.

also is it natural that when i unbolted my front driveshaft some 90wt oil came out from the concave center of the before mentioned disk (but the one on the front diff, the one with less slop)

 

[CruisinGA]

how much is catching enough to be a problem. it rotates fairly freely, i kind of sense a sticking on one axis, but doesn't feel enough.
I would consider any sticking too much, try to grease it up really well and see how it does

is the 3rd member the round disk thing coming out of the diff that the drive shaft bolts to with the 4 14mm bolts.
The third member is the entire casting that bolts to the axle housing, and has that "round disk" (driveshaft flange) sticking out of it.
that disk seems to have a fair amount of slop. is this natural, or fixable.
By slop do you mean wiggling it around or twisting it to see when it hits?
If it wiggles, your pinion bearing is gone, if it twists your R&P is on its way out

also is it natural that when i unbolted my front driveshaft some 90wt oil came out from the concave center of the before mentioned disk (but the one on the front diff, the one with less slop)
That would mean that your pinion seal is going.

I'm now leaning towards a shot pinion bearing, replace that along with the pinion seal and see if that helps. Grease up the u-joints good.

 

[bad_religion_au]

more wiggles, like up and down.

could the pinion bearing be the vibe problem?

is it a hard job to do yourself, i've never torn down a diff or transmission, mainly brakes and the like. do i need special tools, a torque wrench and the like.

ohh, and the leaking diff fluid was on the FRONT diff, the slop in the disk thing was on the REAR diff.

PO sucks. i will shoot him, no maintanance, and he promised spare parts with the rig when he "cleaned out the garage", now he won't return my calls.

Is there a writeup on this procedure, pinion bearing

 

[CruisinGA]

I can't really help you on the procedure, my mechanic did it when he found the leak while it was at his shop. I can come back later today with one secondhand, cause I have to go see him and pick up the cruiser so I can bolt on my new TSL's
As far as the front diff, all you need to do then is replace the pinion seal and not the bearing, I will ask about that procedure as well today. I really have no idea of whats involved. The pinion bearing could be the problem/part of the problem. It needs to be replaced regardless.

 

[bad_religion_au]

thanks for that, anyone else out there that can advise me for/ against trying it myself.

 

[bad_religion_au]

after cruising around in my bro's Hj45 for a month or so, it became time to look at my vibration, needed a new U joint, and got the bugger balanced (i used a shop to do the uni because the balance and 2 uni's were only slightly more expensive than the cost of 2 uni's, and i ended up only doing one, so i saved)

bad news, the vibration is still there. badly. i'm leaning towards diff. when i back off now from speed i get an intermittant whining sound. so it's back on the lawn untill i can get the funds for diff work.

 

[theo]

[quote author=bad_religion_au link=board=1;threadid=4433;start=msg46550#msg46550 date=1065022131]bad news, the vibration is still there. badly. i'm leaning towards diff. when i back off now from speed i get an intermittant whining sound. so it's back on the lawn untill i can get the funds for diff work.
[/quote]

I think you should try the diff rebuild yourself. It's just gears and splines and shafts on a nice, easy to comprehend scale. There is some skill needed to measure backlash and add or remove shims to correct it. But if you end up only needing to replace bearings and seals you may not need to change the shims.

And being the addict that you are, you know where to come for help! As long as you can get the parts you need in Oz.

And there's bound to be a mechanic or two right here that can say right off how tough it is. If nobody steps up, I can read the procedure and look for any "special" tools or procedures that might set you back.

 

[roscoFJ73]

[quote author=theo link=board=1;threadid=4433;start=msg46596#msg46596 date=1065028827] As long as you can get the parts you need in Oz.

Theo definately no parts problem here lol
Bad_religeon Have you checked the output flange on your transfer case for movement[/quote]

 

[bad_religion_au]

1st question. i was told that at an outside chance it may be the crush sleave was worn/ crushed. can i just try tightening the pinion nut back up to stock torque, will that work or do damage? if it involves pulling it all out, i'll just rebuild it.

transfer case output flange is tight as... well tight. i have more slop in the pinion flange on the rear as i do on the front (like twice as much) so i figure sort that out and see.

a friend of mine is getting me a deal on bearings and seals, and he'll help me (like with the measuring backlash) he did 3 years as an aprentice mechanic before throwing it in and becoming a qualified buttcrack

he's done his pinion bearings, and his ring and pinion. i'm concerned it may be ring and pinion (only because i always fear the worst case) is there an easy way to tell before i order the bearings? looks like i gotta bust that drain plug off (PO hit it on something solid and the protective ring is bent onto it.)