Vibration/Noise - Bad Transfer Case?

[texas30cal]

Not 100% sure about these axles but in my experience 1/16" of play (wear) in any bearing is bad.

 

[Jericho]

There is a preload measurement in the T.O. will have to look it up, bearing inspection in its self is easy. During a visual with the bearing out , clean it and degrease, roll the bearing in your hand with no preload and with preload, if you feel roughness in the rotation, replace , With hand pressure applied to mesh the bearing observe side to side play, any real play replace . Observe the race and roller / needle surfaces, any visible damage replace, If any bearing is less than fifty bucks and it took an hour or two to get to it , Don't reinstall it, not worth your time

 

[rustystud]

Good fluids and grease were used. Less than 1000 miles ago everything was changed (even the steering box oil!)

Is there any other way to check for bad pinion bearings than lateral play? When I changed the front rear axle pinion bearings, it had noticeable (1/8 inch) play. The rear rear axle seems tight and the front axle probably only has 1/16 inch play at most.

-Will

When you push against the pinion flange (upward movement) there should be "ZERO" clearance. The only play should be the backlash which is usually .008" to .016" on a gear like that. You measure that by "twisting" the flange.

 

[Jericho]

Thanks Rusty , still feeding the pigs, chickens, turkeys and now hit a deer on the way to work, got to cut up a 200 lb deer and look for a bumper and grill.

 

[Wrenchstench92]

What does the noise sound like? And is the vibration small but noticeable or you feel it in the seat?

 

[Corvette1974]

Not 100% sure about these axles but in my experience 1/16" of play (wear) in any bearing is bad.

I tend to agree, but it wouldn't be the first time I have seen a bearing with slight play give good service life....

There is a preload measurement in the T.O. will have to look it up, bearing inspection in its self is easy. During a visual with the bearing out , clean it and degrease, roll the bearing in your hand with no preload and with preload, if you feel roughness in the rotation, replace , With hand pressure applied to mesh the bearing observe side to side play, any real play replace . Observe the race and roller / needle surfaces, any visible damage replace, If any bearing is less than fifty bucks and it took an hour or two to get to it , Don't reinstall it, not worth your time

The pinion bearing failure is very strange - the bearings I replaced in the front/rear axle "looked" fine but were certainly loose. They were also smooth. So I think for these bearings they just lose material until the preload goes away.

 

[Corvette1974]

When you push against the pinion flange (upward movement) there should be "ZERO" clearance. The only play should be the backlash which is usually .008" to .016" on a gear like that. You measure that by "twisting" the flange.

10-4 on that. I will change it, but the question is where is this new vibration/gear sound coming from if that play was already in existent before the trip?

What does the noise sound like? And is the vibration small but noticeable or you feel it in the seat?

Feel it in the seat/body and the sound is a gear noise or bearing noise. More gear sounding though.

 

[rustystud]

10-4 on that. I will change it, but the question is where is this new vibration/gear sound coming from if that play was already in existent before the trip?



Feel it in the seat/body and the sound is a gear noise or bearing noise. More gear sounding though.

The way your describing the "sound /vibration" now is pointing to the transmission not the driveline. Can you take the transmission cover off and do a quick check ? You have checked all the fluid levels of the transmission and transfer-case right ?

 

[gimpyrobb]

Feel it in the seat/body and the sound is a gear noise or bearing noise. More gear sounding though.

Many times that is a result of the short drive shaft connecting the trans and Tcase having loose bolts.

 

[Corvette1974]

The way your describing the "sound /vibration" now is pointing to the transmission not the driveline. Can you take the transmission cover off and do a quick check ? You have checked all the fluid levels of the transmission and transfer-case right ?

Checking fluids today. The transmission shifts *nice* and feels smooth turning the output shaft in neutral/neutral.

Many times that is a result of the short drive shaft connecting the trans and Tcase having loose bolts.

I am checking torque on all bolts today. Will post back with results.

 

[Corvette1974]

Update - I checked all fluids and bolt torques. The fluids were all ok except the transfer case was about 1 quart low. The driveshaft bolts were all ok. The jackshaft bolts tightened up a *little* bit (but were not "loose" by any stretch). All u joints feel tight (no slop) and the pinion bearings all seem acceptable (Rear axles are 100% tight and the front axle has very little slop you can just "hear" the slop and barely feel it)

Any other thoughts? I was thinking about starting it up and putting the trans in gear and the transfer in neutral to listen for sounds. Otherwise, what steps should I take?

-Will

 

[Corvette1974]

I started the engine and put the trans in gear and transfer in neutral, everything was silent. I'm going to take it for a short drive and report back.

 

[gimpyrobb]

Probably those loose bolts!

 

[Wrenchstench92]

FIXED! Definitely those bolts man. Loose a quarter turn or loose a tiny hair. Loose is loose

 

[Corvette1974]

Probably those loose bolts!

FIXED! Definitely those bolts man. Loose a quarter turn or loose a tiny hair. Loose is loose

Haha! I just got back from the drive. I couldn't feel/hear any noise more than usual M35a2 noises. It is tough to diagnose these trucks because of the immense volume. I did top off the transfer case, but it was only a little low (by like an inch per finger measurement) About a quart to top off. Greased the entire truck too.

I tried low range all gears, high range all gears, downshift transfer case, upshift transfer case. Everything I could think of basically. Nothing that I would consider out of the ordinary happened.

It is amazing that those bolts even being slightly loose made that much of a difference. I mean they probably went from 60 ft-lbs to 90 ft-lbs. For safety, should I replace them with new locking (crush) nuts and locktite or just rock it as is?

Thanks,
Will

 

[gimpyrobb]

Rock on, till the noise comes back. Then if its those bolts again you'll know to swap them out.

 

[Corvette1974]

Rock on, till the noise comes back. Then if its those bolts again you'll know to swap them out.

Awesome! I like that conclusion haha in the mean time I will keep chipping away at the rest of the work on the truck....

Thanks for all of the help! I'll keep you guys updated if there are any catastrophic events that occur...

-Will

 

[fsearls92]

Good to hear it's fixed.

 

[Corvette1974]

Good to hear it's fixed.

Hopefully it holds out....are they ever really fixed? Haha

 

[texas30cal]

Good to hear!! Well now I've developed a vibration that is on-off-on-off, high speed like driveshaft speed, going to check the bolts. I did find LOTS of rotational slack in the front pinion, zero up and down movement. All ujoints check out except the front one which has a very small amount of slack.