V2 Diff rebuild + Gear Ratio Swap (4.10)

[maupineda]

This is how I measured the pinion to confirm if I needed to change the depth shim, and by how much.

First I setup the pinion on a precision block, and align the micrometer so that I could have the exact same setup for both pinions, I started with the old one


I also rotated the pinion to verify the runout, it is incredible that the micrometer did not move at all as I spun the pinion.

Here is the original one



and here the new, same, no runout as I spun the pinion, they are cut exactly the same.



then it was all about getting the pinion into the carrier and adjust the preload





Edit: spent time in ISTA last night and reviewed the specs for e36 chassis, and found that the pinion preload should be 2.5nm or 250ncm. I will redo this as I fear I may have screwed up the process.

I also found the carrier preload values which are bearing brand dependent. Will add here.

K = kompact or small
M = medium
G = grob or large

[maupineda]

The carrier preload seems totally loose, so will need to adjust it and start the gear mesh setup from scratch

I hope it won’t be too difficult

Edit: false alarm, I just had to torque the side caps, it is 2nm of preload, which is about midway the spec.

i also gave the pinion a tad more preload to match the side and it is 2nm also.

base on all this I should have little trouble setting the gear mesh.

[bigjae46]

More info on that puller!

[maupineda]

More info on that puller!

This is the one. I bought the version with two cups (orange and black) the one with white adds another size option.

https://www.vevor.com/bearing-inner-race-tool-c_10331/vevor-carrier-pinion-bearing-puller-clamshell-bearing-puller-w-3-clamshells-p_010910863646?adp=gmc&srsltid=AfmBOopBbomOfyf47W0XA47J9-MiFlHlthWGnzUPBZ6FOHDrFtFYIhRkDRQ&gPromoCode=google202412&gQT=1

[bigjae46]

This is the one. I bought the version with two cups (orange and black) the one with white adds another size option.

https://www.vevor.com/bearing-inner-...le202412&gQT=1

F my life...where was this 3 years ago? lol

Just bought one.

[sapote]

1. so before closing the carrier I wanted to see if I could make the ring close to the original position, to my surprise it goes to the same place with and without clutches.
2.The carrier preload seems totally loose, so will need to adjust it and start the gear mesh setup from scratch

I hope it won’t be too difficult

Edit: false alarm, I just had to torque the side caps, it is 2nm of preload, which is about midway the spec.

1. I don't see the pump in the pics but assume you had it when tightening the ring; if no pump then I don't see how you know the locking ring is at its final position.
2. What side caps that affects the pinion bearing preload? The output flange bearings preload should not affect the pinion bearing preload.

[maupineda]

1. I don't see the pump in the pics but assume you had it when tightening the ring; if no pump then I don't see how you know the locking ring is at its final position.
2. What side caps that affects the pinion bearing preload? The output flange bearings preload should not affect the pinion bearing preload.

1. man, you should go back and check. I documented the ring was drilled and tapped before opening, that is how I know it went to its home position. Also there is a photo above.

2. Did not I say CARRIER? Not sure why you are inferring anything related to the pinion.

[sapote]

1. man, you should go back and check. I documented the ring was drilled and tapped before opening, that is how I know it went to its home position. Also there is a photo above.

2. Did not I say CARRIER? Not sure why you are inferring anything related to the pinion.

1. I was referring to your new post's pics showing the locking ring installed but no pump.
2. My bad.

[maupineda]

More “progress”. My expectation that the pinion depth was going to be ok was wrong, despite the pinion top face being equally tall on both, the center point relative to the ring and housing may be deviated and so my depth is a bit shallow. The contact is centered heel to toe, but to close to the face of the tooth. also the backlash was almos same as before, 0.06mm. So I guess RD is not entirely correct, and is still possible that the depth needs adjustment, and not the side shims.

Without tools I will need to do some trial and error and find shims that get me there, I found some original shims ranging from 3.755 to 3.835, so I will aim for the tallest and go from there. I feel I may need a bit more than that, but also some small moves go a long way.

So up for the 3rd round of pinion removal.

Pro-Tip, if you are doing this, DO NOT change your bearings until the very last, as the races are delicate and this thing is heavy, so by removing and installing the carrier from the housing, you risk damaging the races, I also on the first go tightened the pinion much and it did score the race, so my OCD forces me to replace it, so will be at least two sets of bearings.

Here an image from TIS I used to tighten the ring, is not same as ours, but it helps to follow the correct pattern





As you can see backlash was nice and tight with original shims





Now the deal breaker. First image is drive, the second one is coast.

[fattycharged]

So for the noobs, is the coast too inset?


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[Slideways]

So for the noobs, is the coast too inset?


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Not an expert, but the pattern appears to be slightly closer to the face.

https://www.crawlpedia.com/gear_tooth_pattern.htm

[bigjae46]

Yeah, pinion pre-load and crush sleeve is the LAST step.

Set backlash and pattern and THEN change the pinion bearings, races and seal unless there is obvious damage.

I think the 3.85 is the cutoff to where you may need a different shim. The pinion head get smaller as the ratio gets shorter. Then there are the tolerances stamped on the pinion.

Sorry, I would have said something. It’s been awhile since I’ve done this. I do remember always having extra carrier bearings on hand because they can get banged up since you need them installed the first step.

Empty diff case
Carrier preload (need nee bearings/races on)
Install pinion (no seal or crush sleeve)
Set back lash / gear pattern
Disassemble and clean diff (careful with the carrier bearings)
Replace pinion races
Install pinion with crush sleeve and seal
Set preload
Install carrier

[sapote]

My expectation that the pinion depth was going to be ok was wrong, despite the pinion top face being equally tall on both, the center point relative to the ring and housing may be deviated and so my depth is a bit shallow.

Now the deal breaker. First image is drive, the second one is coast.

I'm not surprised that measuring the pinion gear head length on the precision table turned out not a reliable method to find pinion depth. Since the end of the pinion gear usually edged or stamped with the matching pair numbers and other information, so its face is a rough uneven surface, not a reliable for any dimensioning purpose. Most manufacturers added the unique pinion depth on this face so the installers don't have to do trial error method to set the pinion depth.

On the gear pattern, I would use less of the gear marker paste -- only a thin coat -- for a clearer pattern.
Yes, it shows the pinion needs more shim; I would add additional 0,010 to 0.015" shim to see how far the contact pattern moved toward the bottom of the teeth, then reduce the shim if needed.

I would add a sencond the gear marker 180* from the first marker just to be sure the installed ring is flat.

[maupineda]

I finished up setting up the diff. I only added 0.1 shim to the pinion bearing, and now that have seen many online photos, I am not sure I needed to shim it at all. Feel free to comment, my first pattern was a bit high on the tooth but also had a bit larger area, with the 0.1 shim it lowered a bit but the coast side seems thinner? I think is very minor and is fine either way, if it was not so difficult to remove everything again, I would probably take the 0.1 shim out.

all other things came out perfect

2Nm of friction torque for the pinion and carrier unit
0.0025 of backlash

i never updated about the timesert I had to put on the front bushing joint, but that was done also.

[bigjae46]

I finished up setting up the diff. I only added 0.1 shim to the pinion bearing, and now that have seen many online photos, I am not sure I needed to shim it at all. Feel free to comment, my first pattern was a bit high on the tooth but also had a bit larger area, with the 0.1 shim it lowered a bit but the coast side seems thinner? I think is very minor and is fine either way, if it was not so difficult to remove everything again, I would probably take the 0.1 shim out.

I always pray to god almighty before pressing in the pinion that the pinion depth is good and I don't need to f with the shim. Handling all of the diff parts gets tiring with a high risk of a smashed finger.

I didn't catch this before but the marking compound needs to be applied evenly and all the way down into the root. The first pic probably looks high because the diaper rash cream isn't all the way down into the root. Gear marking compound is a little thicker and easier to apply evenly. For anyone doing this in the future...use gear marking compound. I also found out that diaper rash cream tends to smear.

That looked like an adventure! Glad you got through it! I went through 4 crush sleeves on my first diff...lol...wasn't funny then but I laugh now.