Changing differential, gear pattern issue

wdstamper

Veteran Member
May 17, 2014
170
Florida
+1 on Biggearhead. I struggled with getting my pinion depth correct on my new gears and had some whine a week or so ago. He took the time to read my patterns to help me get it right. No more whine. He‘s an expert!
 

camaro71/holland

Veteran Member
Aug 27, 2003
1,648
The Netherlands
I'm sorry if I came across harsh, I'm not giving you guys on here a hard time, I'm just losing patience with myself and the rear end. I guess I was anticipating a job that would take me a couple days and it's snowballed into a couple weeks. I am sure that with your guys help, you'll walk me through this and I'll have it together soon.

Yes, thank you, this helps greatly. I've had this thing apart likely 30 times and each time it's a pull the bearing off, warm it up, slide it on, wait til it cools, load it in, check rolling torque etc. Very time consuming. I'm super stubborn and hate paying someone to do something I'm capable of (or so I thought).

Should I try let's say, .026 and .027, or does that small of a difference not really matter? All my patterns from now will be measured with .009" backlash.
You're not being harsh in any way, it's just that the patterns that are a b$tch to read...

Went through your pictures again and I still prefer the 28/8 setup. 1 - 2 thousand changes are ok for fine tuning, won't work when chasing ghosts (pattern).
 

NTMIDATR

New Member
Jun 20, 2022
15
I'll get at it again today and will focus on the .028 area. and keep my backlash right at the .009". I was adjusting the backlash to see if it would shift the pattern on the tooth from heel to toe, but as you said, it has little effect. I have a fairly stout small block in here and it may or may not drown out the gear noise if there is any. I usually wear ear plugs when driving more than 20 minutes. It has 3 chamber flowmasters on it and it still sets off car alarms in some cities.
 

NTMIDATR

New Member
Jun 20, 2022
15
Now that our price of gas has come down 25 cents a litre from when I started this job I'm gaining ambition to get it done. Finally tracked down some actual gear marking compound too, man this stuff is hard to find around here. I got a miniscule package 1/4oz and a brush for $10, do what you gotta do I guess. Lol.

I did a setup of .030" pinion shim and the .009" BL from disassembly. Maybe it's me over thinking things, but is the pinion too deep now? I did brush strokes from root to crown, you can kinda see where the gear has swiped them smooth on the coast side
 

Attachments

  • PXL_20220704_024800723.jpg
    PXL_20220704_024800723.jpg
    217.3 KB · Views: 34
  • PXL_20220704_024717245.jpg
    PXL_20220704_024717245.jpg
    167.1 KB · Views: 34

camaro71/holland

Veteran Member
Aug 27, 2003
1,648
The Netherlands
I was breaking my head over your pics. No logical changes to the pattern after change in shims.

Went over your posts to find leads and might have found something: you say you heat up the bearing to place it over the pinion. This might be your issue.... I question if the bearing is bottoming out on the shim using this technique.

I use a hydraulic press and try to set it using the same amount of force every time. So I don't stop when I THINK it's touching the shim, I give it an extra push till I see the pressure build up to 1 ton every time and stop there. This gives me the chance to repeat the process the same way every time within my possibilities.

I don't think you set the bearing correctly by heating it and therefore get a different pinion to ring distance than you should by changing the shim.
 

NTMIDATR

New Member
Jun 20, 2022
15
I was breaking my head over your pics. No logical changes to the pattern after change in shims.

Went over your posts to find leads and might have found something: you say you heat up the bearing to place it over the pinion. This might be your issue.... I question if the bearing is bottoming out on the shim using this technique.

I use a hydraulic press and try to set it using the same amount of force every time. So I don't stop when I THINK it's touching the shim, I give it an extra push till I see the pressure build up to 1 ton every time and stop there. This gives me the chance to repeat the process the same way every time within my possibilities.

I don't think you set the bearing correctly by heating it and therefore get a different pinion to ring distance than you should by changing the shim.
That makes total sense. So what I have been doing to prevent this is maybe what's causing my inconsistent results. I would leave the shims out of my crush sleeve eliminator kit, crank the pinion nut down tight until what I thought was the bearing seating on the pinion then back it off, tap it with the rubber mallet, then tighten down until I reach the 18-20in/lb.

What I will try to do now is since I don't have access to a hydraulic press other than at work. I will heat the bearing, then use the bearing puller on backwards and pull the bearing into place. I think it will clear the roller cage on the bearing, if not, I'll just take it to work with me everyday and seat the bearing until we get this sucker set!!

Thanks for the response, sometimes it takes another set of eyes and brain to troubleshoot stuff like this.
 

camaro71/holland

Veteran Member
Aug 27, 2003
1,648
The Netherlands
Hold your horses.... I'm not sure were talking about the same thing.

I was referring to the large bearing on the pinion, directly over the pinion shim. I thought you were heating that bearing to pull it on/off.

You are talking about the crush sleeve eliminator and the small bearing on top of the pinion.

When I'm installing a solid shim, that's where I start the build up. You'll have to go through process any way, so why not at the beginning and then yank the (old) pinion nut on every try without worrying about the preload?

2 or 3 leg pullers won't do the job, or will destroy the bearing by pulling on the cage. There is just not enough space to get grip on the bearing itself. You need a scissor type puller and a press to do the job correctly.
 

NTMIDATR

New Member
Jun 20, 2022
15
Yeah that's what I meant. I'm not adjusting the pinion rolling torque spacer and shims at all, I'm just changing the shim under the big pinion bearing. I looked around at work and couldn't find a tube long or big enough to press that bearing on, I'm going to keep looking, there has to be something somewhere.

Tonight I heated the bearing, slid it on the pinion, then while it was still warm I put the pinion in without the preload shim and spacer. I put the yoke on and torqued the nut to 110 ft/lbs just to make sure the bearing was fully seated. Then I removed it and put my preload spacer and shims on and set to 20 in/lbs.

I did find the limit to where the gears don't want to be set. The .038 shim was noisy just rolling over by hand, but was curious to see what would happen to the pattern.

Would a picture of the gear faces be beneficial, so you can see if that's my problem. They do have some miles on them. I've put on maybe 35,000 miles, and the used rear end they came out of it was unknown, but the vehicle was bone stock. The pinion teeth on the drive side are a mirror finish.

Is the .030" my next step?
 

Attachments

  • PXL_20220707_021117467.jpg
    PXL_20220707_021117467.jpg
    207 KB · Views: 16
  • PXL_20220707_021105707.jpg
    PXL_20220707_021105707.jpg
    221.2 KB · Views: 22
  • PXL_20220707_012604533.jpg
    PXL_20220707_012604533.jpg
    218.6 KB · Views: 21
  • PXL_20220707_012546386.jpg
    PXL_20220707_012546386.jpg
    197.6 KB · Views: 20

camaro71/holland

Veteran Member
Aug 27, 2003
1,648
The Netherlands
Ok, that's the next piece of the puzzle..... used gears. That means you have to focus/read the pattern of the coast side.

Went through the pics again and like the 25/6 & 28/8 patterns the most (coast side).

Still, doesn't mean sh$t if you don't set the bearing correctly.
 

NTMIDATR

New Member
Jun 20, 2022
15
Ok, that's the next piece of the puzzle..... used gears. That means you have to focus/read the pattern of the coast side.

Went through the pics again and like the 25/6 & 28/8 patterns the most (coast side).

Still, doesn't mean sh$t if you don't set the bearing correctly.
I'll give those a try next. Would you go any lower than .006" backlash to move the pattern to the optimum spot?

I was originally thinking just put new bearings on reuse the old shim and slam it back together. Boy was I wrong, here I thought it was going to be a 6 hour job, removing rear end, changing differential and bearings then putting it back in. Lol way she goes!
 




Latest posts

Top