Gear pattern check.

Bump for me

D80 rear, 6.17s, all dummy bearings still.

First time setting up new gears. Used an old ass Karl jantz video for tips.
20250502_182326.jpg
20250502_182330.jpg
20250502_182335.jpg
20250502_182338.jpg
Backlash? I'd say they look a tad deep.
 
Little hard to read but looks good.

I always thin my paint with a drop or two of gear oil and then run the pinion with a drill while dragging the ring gear with my other hand. It really makes a good readable print.

91FD5E97-45C7-4CD2-8419-14D0226C2425.jpeg
 
Good idea, I guess I could put my 1/2 square adapter in my drill. I tried it a bit with the m18 impact and it was enough drag it wouldn't spin without impacting.
 
Okay fellas. Finally got the new elite gears installed (Ron's Machine Service in Michigan.)

Current set up.
8" BL 75 thou pinion shim (includes 30 thou slinger)
I like that it's deeper for standard cut gears in the front.

1000008737.jpg
1000008736.jpg



Intital setup

5" B/L 80 thou pinion preload
1000008734.jpg

1000008735.jpg



Should I pull another 3-5 thou or just stick with my current 8 thou B/L? I do like it's a snug deep.
 
Well all new bearings in set carrier preload tight, pinion preload is nice and smooth at 25 in lbs. 30 in lbs with seal.

Ended up 6 thou B/L.

Pattern is still a touch deep but I want that for a front to keep the load off the high points of the teeth coast side. (in my opinion, it ain't worth ****.)

I ran it with a drill in both directions for 5-10 min with shafts and oil in it and its nice and smooth.

Fingers crossed, going to run this one in with no driveshaft and hubs locked. 20 min drive let it cool. If I feel any vibe it gets shut down and I will be temp gunning the top pinion bearing every few minutes.


P.S the new gears from Elite/ Ron's set up well and smooth. He offers a lifetime one time replacement.

But states no synthetic...

I'm breaking in with 85-140 and will prob jump to redline heavy shockproof.
 
Hate to say it but I'd go shallower, that's a little deeper than I'd personally be super happy with on my own junk.

Front low pinions pull themselves deeper into mesh during forward acceleration, then drive themselves out of mesh while reversing. Then the opposite of that is true for high pinion fronts
 
Hate to say it but I'd go shallower, that's a little deeper than I'd personally be super happy with on my own junk.

Front low pinions pull themselves deeper into mesh during forward acceleration, then drive themselves out of mesh while reversing. Then the opposite of that is true for high pinion fronts
Hmmm. Interesting. Will see how it goes.

I believe you 100%.
 
This is absolutely ******ed. No vibration at all... Within 5 min of having hubs locked I pulled over to check pinion bearing temp and it was 240 degrees. It's not getting any lube up to the top bearing

Pinion is up at 15-16 degrees

Gear oil was only 100 deg going by temp of the cover.

This makes no friggen sense it's all the same setup I had already been running before.

Luckily this time I can still turn the pinion and didn't wreck the gears. I'm at a loss as to what to do.

Nothing was wrong with the carrier bearings before so it's not gear set up.

Preload was only 20-25in lbs on this setup.

I'm wondering if the aftermarket cover isn't allowing the oil to sling up into the pinion...

Even though it's the same cover I've been running for years.
 
Edit.

****** moment of brains happened with my friend on the phone


Got me to measure actual pinion angle. And caster.

When I built this axle rotated the pinion to have 15-16 degrees and had the knuckles at 6-7.

Pinion is at 21.5-22 and caster is sitting at 0-1...

I think in the accident it bent my whole front frame down so much that it put the pinion so high that maybe the oil isn't getting to it.

Will 6 degrees make that much of a difference? It must.
1000008783.jpg
1000008782.jpg
 
So hubs are locked, but tcase still in 2wd so it's just freewheeling, and you're getting those 240* pinion temps? Yeah that seems super strange to me. I don't think it has anything to do with the depth, just preload/oiling oddities. You have a decent amount of pinion angle, but this is a low pinion we're talking about here. The ring gear should be paddling plenty of oil into that lower pinion trough to feed the bearings, even if the oil fill level was lower than the outer pinion bearing.
 
Dumb question but is there anything blocking the oil galleys? Did you leave out any oil slingers? I would start looking for simple stuff, I wouldn't think the pinion angle would affect oiling that much.
 
Dumb question but is there anything blocking the oil galleys? Did you leave out any oil slingers? I would start looking for simple stuff, I wouldn't think the pinion angle would affect oiling that much.
The only slinger I didn't put in is this one. It's not used in a stock GM low pinion.
1000008784.jpg


I cleaned out the oiling paths of all rollers that were stuck in there.

I've ordered a new outer bearing yet again. Going to **** with the shackle angle and see if I can rotate that pinion back to get my caster back too.

This is stupid lol!
 
So hubs are locked, but tcase still in 2wd so it's just freewheeling, and you're getting those 240* pinion temps? Yeah that seems super strange to me. I don't think it has anything to do with the depth, just preload/oiling oddities. You have a decent amount of pinion angle, but this is a low pinion we're talking about here. The ring gear should be paddling plenty of oil into that lower pinion trough to feed the bearings, even if the oil fill level was lower than the outer pinion bearing.
I didn't even have a driveshaft in. It's a plate front diff cover so maybe it doesn't allow the oil to sling up there smooth? I even smothered that bearing in Lucas assembly lube.

The fill plug on the front of the housing is prob at the bottom 1/4 of the carrier bearings.
1000008785.jpg
 
I didn't even have a driveshaft in. It's a plate front diff cover so maybe it doesn't allow the oil to sling up there smooth? I even smothered that bearing in Lucas assembly lube.

The fill plug on the front of the housing is prob at the bottom 1/4 of the carrier bearings.
1000008785.jpg
Low pinion fronts have **** oiling to the pinion. Open up and Dana LP diff and right in line with the ring gear there's a hole that the oil slung by the ring gear will take right down to the pinion. You run it in reverse and you only get a fraction of that oiling. Combine that with ******ed pinion angle that gets the bearing way up there and it explains your problem.

Put a new bung on the cover and run a higher oil level.
 
Low pinion fronts have **** oiling to the pinion. Open up and Dana LP diff and right in line with the ring gear there's a hole that the oil slung by the ring gear will take right down to the pinion. You run it in reverse and you only get a fraction of that oiling. Combine that with ******ed pinion angle that gets the bearing way up there and it explains your problem.

Put a new bung on the cover and run a higher oil level.
Okay I will do that. Because as it is I'm only getting 2.5 qrts in. (arb carrier) stock is something like 3 qrts.
 
Got lucky fellas, loosened pinion nut and she spins nice and free. 25 in lbs was just too much preload with no oiling.

But I didn't roach another gear set thankfully.

24 hrs awake after last night's 12 hr shift!

Said frig it. Let's get this axle out and sorted! Perches cut off. Going to rotate them 4-5 degrees forward. Get back to 15 degree pinion angle.

1000008801.jpg
1000008802.jpg
 
Cut the perches off, rotated the 5 degrees forward. Had to lower my tie rod as it was hitting the spring on the pass side.

Welded perches back on, swapped the pinion bearing, added 3 thou to pinion shim. Bastard showed less than 10 inch lbs fully torqued. Siad screw it torqued the yoke down and we will run it. (packed bearing with grease just in case)

Today I finished this bastard. We went from 0-1 degree of caster to 7-8 degrees of caster. 14.6 degrees on the pinion.

Its back on 4 wheels and I still get my father's day test drive!
1000008849.jpg
1000008850.jpg
1000008851.jpg
1000008852.jpg
 
Last edited:
I've been working off and on and for a month now, but now I need to get it done.
I last worked on this a couple a weeks ago. Motive pro gear, 4.29 ratio in a Strange Pro HD housing.
I should've taken pictures then, but back on it now. .008 backlash
Coast side always looked too close. I've just been concentrating on the drive side. I just now thinned the marking compound with gear oil and it looks like I' m a little too close on the drive side also.
Edit- these photos were with .013" of shim (.008+.005)

20250708_201840.jpg
20250708_201911.jpg
 
Last edited:
Well threw in .02" in with the .013 I had before for a total of .033" pinion shims back-lash set at .008" coast side still looks terrible, but drive shows the pinion looks too far away.( I think)
20250709_164142.jpg
20250709_164222.jpg
 
Last edited:
.02" pinion shim. Left the back lash alone since it came out .009". I'm thinking of tightening the back lash a little but I'm limited to were the adjusters land where I could put the "locks" in place.
20250709_185422.jpg
20250709_185504.jpg
 
Yeah, I like how centered the pattern is in tooth. The sharp line in root bothers me a little. I may go back to that if I don't hear from somebody else.
 
Last edited:
Top Back Refresh