Front Drive Shaft grrrrrrrrr findings so far. .

[sleeoffroad]

How was the pinion seals replaced? If done with the third member in the truck, this could be where some of this is coming from. It can be done on the truck, but you must know what you are doing and even then it is not the best way to do it. Did they replace the crush sleave? Did they test the pre-load after replacing the seal?

 

[sleeoffroad]

Is there any test to confirm a bad output bearing on the tcase or the front pinion?

With the driveshaft removed, you can see if you can move the flange back and forth? It should not be loose. Basic test but the bearing might still be tight but pitted and damaged, especially if you got water or dirt in there at the time that the seal was leaking. Oil goes out, dirt can go in.

 

[Cruiserhead05]

Christo,

Unfortunately when the pinion work was done i didnt have much involvement.....i was too burried in a 40 i was playing with. I really cant answer any of these question, which i do regret. I'm trying to do more work with the 80 and have less people touch it.

 

[concretejungle]

I also can’t answer the questions about the pinion seal replacement. I had a shop do it, as I thought it required taking the third member out. I can ask the mechanic who performed the task.

I do find it ironic that Brandon and I both have had pinion seals replaced and we both are dealing with this weird vibration.

Also, I don’t think the shaft is “too short” so to say. When we pulled the front out from the rear and measured, it indicated that when installed there was several inches still up in the sleeve.

 

[Cruiserhead05]

Question,

If this vibration and grinding sound was a bad pinion bearing wouldnt taking the front d/s off effect it? When the the grrr is happening i can feel it slightly in the floor pan, removing the d/s seems like it would effect how bad it was b/c without the driveshaft there is less ability for the "grr" to transfer up into the body.

Hope that makes sense.

 

[sleeoffroad]

Brandon, can you feel it with the front DS removed?

 

[Cruiserhead05]

Christo,
I'm slacking here. I havent had the ds enough to drive it around. Obviously it was off when i had the U's installed but i couldnt go out and drive it. I'm more or less talking about Concrete situation and how he drove his 80 for a day w/o the front D.S.
Does it make sense that if it was a pinions bearing, removing the front d.s would effect it?

 

[fj803fe]

Christo,
I'm slacking here. I havent had the ds enough to drive it around. Obviously it was off when i had the U's installed but i couldnt go out and drive it. I'm more or less talking about Concrete situation and how he drove his 80 for a day w/o the front D.S.
Does it make sense that if it was a pinions bearing, removing the front d.s would effect it?

If its your front shaft-you'll know when its gone and no GRRRRR. If it is the pinion-the grrr is likely to be much reduced once the shaft is off-but might still be noticeable. I'd go with feeling for flange "play" w/ the ds removed too. If the bearing is shot you might have a little play in there.

Though typically if you have had this grr for some time driving around and it is the pinion bearing then the "play" and vibration through the driveline can result in pinion seal leak and you may have some sweating of gear oil in that area. BUt the seal may also be fine and the bearing is still bad...

I'm no friggin help ..."it could be this, but then again it may not be..." GEEZ-I've been on the computer too long. - I'm going to put new hub bearings in the 100

I'm worse than I thought! I see your pics now-no sign of seal leakage :whoops:

 

[powderpig]

If done right and with common sense doing the pinion seal on the truck is OK. On the truck you can not get a reading for bearing preload. Not all seal failures are do to loose bearing, but a good majority are. If caught early and no pitting of the bearing(felt by ruffness when spining the flange, then all sould be OK). If left too loose, or tightened too much then failure is going to happen. Either jack both tire up or have one tire off the ground, rotate the flange and see if any ruffness in the bearing by making slight movements back and forth. You should be able to feel backlash (can be alot in high milage vechicles), but it should not be loose to the point of moving the flange up and down. If it feels gritty when rotating it then you have a problem.
T-case out put bearings are a ball roller type of bearing, they will have some up and down movement and in/out movement. Think about they type of bearing and then think on how much movement you should expect in these directions,some but not alot, Anything over 1/16 to1/8 is probley too much and need some attention.
As to why after a lift, well you are stressing all these areas in different angles, after they have been riding in a pattern for many many miles, now all of a sudden they are being asked to ride in a different patteren, some with less support in these angles. Could also find a shop with Chasis ears and lissen for sounds on these, I have found these to help alot.
Also Ken Romer was chasing a problem in what sound like the front and it ended up to be the rear drive shaft(what a pain that was, not ken, the problem). Sound is a funny tool for chasing down problems, it something is hard to hear where the problem truly is. good luck robbie

 

[brianinaustin]

FYI from a fellow growler.....

- Without front driveshaft, growl is gone.
- Loading the Cruiser with seven passengers makes the grrrr go away.
- There is no play in either flange.
- I do not have Slee's plates.
- I have at least an inch between my tie rod and control arm.

This started immediately after the 2" lift. I don't see bearings being the cause.

 

[landtank]

Was curious, has anyone with Christo's plates put their truck up on an alignment rack to see what the end result is?

I'm just thinking that there might be a lift/caster relationship to this problem. I'm not saying that the caster is out of spec but maybe just in a spot that lends itself to this sort of problem.

 

[alia176]

I'm curious...is it bad to have the slip joint out that much? Mine is about the same as Concrete's. My driveshaft shop made it about 1.25" too short when converting it over to a DC driveshaft.

 

[aamiggia]

Does anyone have/had this problem on a stock suspension?

I'm getting a GRRR sound and slight vibration in the floor and I have the original suspension. It starts at 50 mph and peaks at 65 mph. I'm almost sure mine is worn out u-joints.

 

[concretejungle]

Does anyone have/had this problem on a stock suspension?

I'm getting a GRRR sound and slight vibration in the floor and I have the original suspension. It starts at 50 mph and peaks at 65 mph. I'm almost sure mine is worn out u-joints.

I spoke with another mudder last night that has his truck completely stock except a bull bar in the front and he has the same grrrrrrrr

 

[Bob_Garrett]

I'll toss in my experience with the Grrr noise.

Stock truck - no noise

2.5 Heavy OME - Noticed noise for the first time.

Added ARB and 12k winch - slight decrease in noise

Added MTRs - couldn't hear it anymore

Added J springs/ 1" spacers and Slee front arms - noise now overcomes the MTRs and can feel some vibration as well

Replaced u-joints - vibration decreased - Grrr sound still there

Installed one of Christo's double-cardan front shafts - noise and vibration gone

Between the time that I put on the 1st OME and switching to MTRs, I drove the truck over 40k mi and the noise never changed and I had no pinion seal or tcase problems.

 

[concretejungle]

My plan now, is to grind the control arm enough to get the tie rod off it. Then check for play in the output bearings. If that fixes it, then great. If not, then i'll put a DC shaft in.

 

[Cruiserhead05]

Something i've noticed, and i could be wrong....but the grr seems to totally be gone when the truck is cold, its almost as if it gets warm when the truck heats up.
I am going to try some weights on the front end tomorrow and will report back with my results.

 

[concretejungle]

Something i've noticed, and i could be wrong....but the grr seems to totally be gone when the truck is cold, its almost as if it gets warm when the truck heats up.
.

I noticed the exact same thing. Especially noticed it when i had the driveshaft off the truck and checked for play, none. Put the shaft on the truck, drove down the highway and to a shop, then took it off after it was hot and inspected it for play and felt a little in the slip yoke. I just figured it was the grease loosening up.

 

[brianinaustin]

Dude, me too!!!! Forgot to mention that it has to warm up first. WTF?

Does the DC driveshaft require any shimming, or is it a drop-in replacement?

 

[landtank]

then took it off after it was hot and inspected it for play and felt a little in the slip yoke.

I've replaced both my shafts for loose slip yokes. This can be hard to detect and you need to grasp the axle in just the right spot to feel it. If your hand is a little forward or aft of this spot the axle will feel tight. Basically grab the outer tube at the end and move the shaft up and down. At the end you'll probably not feel any play. Then move you hand back about 1/4" and check again. I know it doesn't seem like much but the hand placement is critical. Keep repeating down the shaft for about 6". Once you feel a bad slip yoke it will be easier the next time.