Sinking Creek 4WD Association

Decided it would be a good idea to tear my front axle apart to see if there were any gremlins hiding in there and all looked good till I saw this.

After looking it over good I dont see where anything is off with the setup. The backlash feels tight, there is no noticable movement in the pinion or the carrier. I smacked the pinion with a hammer to see if it there was any movement and there was none. Ran a rough gear pattern check and it looks decent. Its spread out pretty evenly across the middle of the teeth. The only thing I can think is that the pinion was put under enough force to deflect into the carrier at some point. The amount of clearence between them is pretty small. Unless someone can come up with a reason not to I am going to stick it back in and run till it dies.

The way it sits, the pinion depth is really high (as in real close to the center of ring gear). When the pinion is put under a great load it will deflect away from the carrier, so youll actually be running a nice center contact pattern (because the pinion is biting into the carrier under load. Im sure you know all this, but Id leave it like it is since its just a trail rig. The guy who runs crozet sets up his gears like that (with a low backlash and pinion depth) for that reason.



Edit: on second thought, since it is your front axle, the pinion might deflect toward the carrier like you said, Im not too sure on that (i guess it depends on whether its high Pinion and reverse cut etc.). But point is I think you should leave it.

alk1174 wrote:Decided it would be a good idea to tear my front axle apart to see if there were any gremlins hiding in there and all looked good till I saw this.

Well there's your problem, you took something apart looking for something wrong.

I have no actual technical input, that is really interesting though I've never seen that before.

is the pre-load still good?

shmoken875 wrote:is the pre-load still good?

It still feels good checking it by hand and it does have solid spacers instead of crush sleeves. Without a complete disassembly I wouldnt know for sure.

is it possible that the carrier had those marks before you installed the 5.29s? Every 3rd that I have ever seen with worn pinion bearings has those same teeth marks. Got 3 of em in the garage that look like that.

I wondered about that also Stinson but I do not recall having any 3rds with pinion marks on it. I believe this 3rd was one from a front axle so it should have had low mileage.

I'm with Stinson. I've got a collection of carriers that look like that.

Maybe clean it up really well and put some bright paint on it and see if the pinion takes the paint off over time?

I am almost positive the marks werent there before but I also dont see how it could happen with everything still being as tight as it is. For curiosity I took the 3rd out to Tim at Pride and Joy who set the gears up a few years back. He looked them over and also did not see anything suspicious. I will apply a little paint to the marks before I stick it back in and see what happens.

Arya Ebrahimi wrote: Maybe clean it up really well and put some bright paint on it and see if the pinion takes the paint off over time?

The problem with this thought is that it requires taking it back apart BEFORE it breaks. That is definitely against my policies.....nothing comes apart until AFTER it breaks. Even then it sits broken for a while.......

For example: My front detroit has been broken since November of 08......used the truck this weekend and guess what.....the detroit still hasn't fixed itself yet!!

Trailduster79 wrote: The problem with this thought is that it requires taking it back apart BEFORE it breaks. That is definitely against my policies.....nothing comes apart until AFTER it breaks. Even then it sits broken for a while.......

For example: My front detroit has been broken since November of 08......used the truck this weekend and guess what.....the detroit still hasn't fixed itself yet!!

See what happens once you get a tow rig and a trailer!