M1009 was making aweful sounds, took it apart, and cannot find a thing wrong with it.

[Loco_Hosa]

This started about 1000 miles ago with a small trailer filled with rock. On the way home it made some speed related, low growling sounds. The locker also might have been misbehaving, locking and unlocking during a normal turn.

The next day, no trailer, but still making the aweful sounds. Took the diff cover off, nothing obviously broken so I filled it with clean gear oil and tried again. Really no change.

Now I've torn the carrier out, removed the pinion, and I can't see anything that looks jacked up. Everything looks fine. I expected to find a bearing that was obviously dead, but no.

U joints are fine, and the transfer case output doesn't seem to have any slop. I'm out of ideas.

Amy thoughts of where to point my flashlight? Any advice? Anyone want to spend a weekend swapping a 14 bolt in with me?

 

[Bighorn]

Speed related growling sound.
Sounds like a pinion bearing.
Since the front was unlocked and driveshaft no turning, it most likely is the rear.
How about removing the rear driveshaft and taping a soda bottle over the output of the transfer case and then locking it into 4wd and carefully driving it?
I did this once when I blew up my rear driveshaft wheeling.
Just take it easy in turns on pavement.
That way you can eliminate the rear driveshaft for sure.
Axle bearing maybe?
Usually but not always, a bad axle bearing will be preceded by an oil leak out the rear brake backer plate between the drum and plate.
A chipped ring gear will make a repetitive clunk sound.
A chipped pinion gear will be a much high pitched and faster vibration/clunking noise.
Pinion bearings or axle bearings is my guess.
Jack up the rear and remove the wheels and drums.
Look for oil leaks.
Grab the axle flanges and lift up and down.
Should be no play there.

 

[Rustyshackelford]

Id look closer at the u joints and then upgrade to one tons.

 

[edpdx]

wheel bearings. Also revisit universals- I put a rear uni in but didn't get the retainer right. too soon to fail,I overlooked it.

 

[snowtrac nome]

look at u joints and the phasing of said joints you would be surprised how many mechanics slip the shaft out of the slip yoke to change a joint than don't put it back together right.
cr@p forgot that has a np208 no slipyoke do take the joints out and check them

 

[cucvrus]

Right outer axle bearing and axle scrap.

I had the roaring grinding sound in my Terminus M1009. I had a multitude of issues with the vehicle at the time. both u joints were bad and the caps were turning in the yokes. Then I pulled the axles and found this on the right axle. at this point I replaced both axle bearings and scrapped the right drive axle. they make axle saver bearings for correcting this issue. that is a worthless repair. The end result is you have the axle riding on the axle saver bearing at a different location. That is like stop leak to me. Fix it right while you have it apart. Back in 1996 when I had the chance I bought a few NOS M1009 crated F & R axles. I still haven't opened any crates. If it were my truck I would look closely at the outer axle bearings.

 

[Loco_Hosa]

Thank you everyone for the help, I'm going to hopefully have a chance to take a closer look this weekend. Now I'm wishing I had stopped taking things apart a little sooner before having to ruin the pinion seal and cross pin.

I'm sure that the ujoint wasn't the issue, and I had assumed pinion bearing. Can't see anything wrong with it, but I'm getting a second opinion this afternoon.

Wheel bearings are worth another look as well, thank you!

I have a 14 bolt and a Dana 44 in a rusty parts truck out back, the eventual plan being that these axles are going under the M1009, but that is down the road a bit. I'm hoping to get the 10 bolt functional again in the interim. I'm also hesitant to spend a dollar on the 10 bolt unless I can be sure I've found the issue. Just to put it back together at this point I need a new pinion seal, new cross pin and retaining bolt, and the brakes are shot.

 

[gimpyrobb]

Spend your time and money rebuilding the stronger axles and put them in, no need to waste time, money, and effort.

 

[Loco_Hosa]

Spend your time and money rebuilding the stronger axles and put them in, no need to waste time, money, and effort.

I was hoping to spend my time and money doing some work on my Cummins, so I was thinking this would be a quick cheap fix. I wanted to be able to drive the M1009 while I had the Cummins torn down.

I am starting to think my plan may have to change.

 

[corelokt]

Check your grill guard for fur, gristle, sneakers...

 

[Loco_Hosa]

Well, I brought the carrier, pinion, and bearings to have Grand Pa help me look them over. As soon as I had things on his well lit workbench I started to see that the gears are not pretty. His words were, ”these are the ugliest gears I've seen that are not broken” and we found the pinion bearing inner race rotates on the pinion shaft.

Looks like I'm swapping to 3/4 ton running gear sooner than I thought. Thank you everyone for being helpful!

Next thing I need to do? More workbench lights.

 

[edpdx]

Next thing I need to do? More workbench lights.

Nope, next thing is get Grand Pa to give you a sitrep before you do all that work.

 

[corelokt]

Sounds easier to replace the axle than repair yours. Going full floater?

 

[Chaski]

Well, I brought the carrier, pinion, and bearings to have Grand Pa help me look them over. As soon as I had things on his well lit workbench I started to see that the gears are not pretty. His words were, ”these are the ugliest gears I've seen that are not broken” and we found the pinion bearing inner race rotates on the pinion shaft.

Looks like I'm swapping to 3/4 ton running gear sooner than I thought. Thank you everyone for being helpful!

Next thing I need to do? More workbench lights.

3/4 ton?
Go 1 ton.

 

[Loco_Hosa]

Sounds easier to replace the axle than repair yours. Going full floater?

Yup, I've got a 14 bolt in an older parts truck out back that should bolt right in. Going to take it apart and clean it, paint it, and probably do a shackle flip while I'm there.

Since that truck has a Dana 44 with matching gear ratios in the front I'll likely swap that too rather than regearing the 10 bolt, assuming there is nothing way wrong inside. [I know the Dana 44 and the 10 bolt have nearly identical strength]

Thinking I'll use the 52 inch rear springs from my parts truck to improve the front end of the M1009 at the same time.

This was always the plan, but I had hoped to do it in about a year after I got some work finished on my Cummins and installed a lift in the shop.

3/4 ton?
Go 1 ton.

So, I might be completely wrong here. Please inform me if I am. The only meaningful difference is the size of the brakes [sometimes] and gear ratios for the rear, and the front got a Dana 60 instead of a Dana 44. Out here Dana 60s are expensive, and I already have a 3/4 set of axles out of a 76. Despite being pretty rough on my equipment from time to time, I've never broken a front axle so it's hard to justify spending the additional cash on a Dana 60 when I have a 44 with the right gears.

If I do manage to kill it I'll call it a learning experience and buy a Dana 60 then. =]

 

[Loco_Hosa]

https://imgur.com/a/swEfX

This was the pinion gear. The wear marks are supposed to look ”not like that.”

 

[corelokt]

If your not running huge tires or going somewhere you can get a tire wedged in and able to put huge torque into it without spinning it, 3/4 is likely fine. Even 1/2 tons last most people in normal use.