1981 Pick-up Build (1 Viewer)

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Well, it sounds like I should give the stockers a chance. Thanks for the feedback.
 
Started tearing down the spare axle for the swap. Going to gusset this one.

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And some perty welds from the PO

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Tore the axles down today to swap the diffs and install the Spartan. Found out why the locker wasn't working- this is exactly as I found it. If you can't see well, the copper line sheared. Do you think this was a poor install and things weren't torqued correctly? It was set up about 4 years ago but the locker didn't stop working until last year. Any potential damage to the gears because of this?

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And a pile of parts

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Tore the axles down today to swap the diffs and install the Spartan. Found out why the locker wasn't working- this is exactly as I found it. If you can't see well, the copper line sheared. Do you think this was a poor install and things weren't torqued correctly? It was set up about 4 years ago but the locker didn't stop working until last year. Any potential damage to the gears because of this?

View attachment 1207585

And a pile of parts

View attachment 1207588

Holy hell, how did that diff even work?
 
Umm, I think the copper line shearing was the least of the issues. The fact that the cap separated from the housing was likely the start of the problems, the line shear was just a result of the cap letting the bearing rotate.

I would pull it all apart and visually inspect everything and then decide how to proceed from there. A few new parts for the locker is very likely all that you will need to put it all back together and have a working locker.
 
Umm, I think the copper line shearing was the least of the issues. The fact that the cap separated from the housing was likely the start of the problems, the line shear was just a result of the cap letting the bearing rotate.

I would pull it all apart and visually inspect everything and then decide how to proceed from there. A few new parts for the locker is very likely all that you will need to put it all back together and have a working locker.

I agree completely - the line shear was definitely caused by the loosening. The other side was also loose but not nearly as bad.

I plan to bring it by the shop next week and see what they have to say.
 
I bet the holes weren't cleaned out, probably had some oil in them, bad torque readings, if they were torqued at all and no loc-tite. Are there any teeth marks on the side of the carrier? If not then the gears probably are fine. New bearings, and set it all back up right and I think you should be good.
 
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Jynx has nailed it as usual, certainly not torqued and maybe not even tightened. If everything looks good and you replace the air line I'd run it.
 
A couple of questions:

1. Should this look like this? This is the open, but soon not to be, front diff. It's hard to tell in the pic, but that retainer (not sure of the actual name) is cockeyed unlike the other side which is not.

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2. Tried to get the cross pin out of the same diff. Would I need to grind into the ring gear to get the pin to slide the extra bit such that it will slide out without pulling the ring gear - I'm running 4.88s? It seems like the amount of grinding would compromise the integrity of the gears.

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The crooked lock tab might be ok, as long as when you remove it the bearing preload ring does not move freely. If the preload was set on those carrier bearings and that is where it landed then they just set it in the one that would maintain the preload on the retainer ring.

In the cross-shaft, the guy that did my gears in the 80 ground a couple of the teeth in order to allow the pin to slide in and out. I believe it is pretty common practice, but I have zero experience with how it should be done. Maybe some of the other guys can offer up some advice on that.
 
The crooked lock tab might be ok, as long as when you remove it the bearing preload ring does not move freely. If the preload was set on those carrier bearings and that is where it landed then they just set it in the one that would maintain the preload on the retainer ring.

In the cross-shaft, the guy that did my gears in the 80 ground a couple of the teeth in order to allow the pin to slide in and out. I believe it is pretty common practice, but I have zero experience with how it should be done. Maybe some of the other guys can offer up some advice on that.

Thanks for the input - I have zero experience with diffs so this feedback is immensely helpful. I'll be at the local shop this week and see what they have to say.
 
Thanks for the input - I have zero experience with diffs so this feedback is immensely helpful. I'll be at the local shop this week and see what they have to say.


Not to discount Matt but I've never seen (or heard of) it done on mini truck but i know Ben did it on his 60 few years back.

We have always pulled the carrier and ring gear to install the locker.
 


Generally it only has to be done for C-clip axles because the cross-shaft has to be installed and removed in order to get the c-clips out (why the 60 rear had to be clearanced as Ted noted above). Originally my rear was going into a 91 SF rear so they had to be clearanced to get them out. In a FF or non-clipped axle you don't see it as often, but I was very glad it was already done when I went to install my Spartan in there a couple of years ago.
 
@jynx - thanks for the info. I tried a little grinding yesterday with the dremel, but I would need to pull the ring gear to grind as illustrated above. I decided to have the shop do the install while they are rehabing the other 3rd - I'll have a little more confidence in the install this way.

@TeddyBoy - although I have the 3rd at the shop to install the Spartan, can you pull the carrier and ring gear and reinstall without having to re-check pattern, backlash, etc.?
 
Just my $0.02 as far as the setup question goes. If the pattern is set and all is good, then pulling the carrier isn't that bad. The pinion depth is the biggest factor in the pattern, so as long as you don't mess with that, then pulling the carrier, and taking the ring off shouldn't be that big of a deal. Make sure to mark the carrier and the ring so it goes back together in the same spot. While I haven't pulled the ring off the carrier, I have torn down one without removing the pinion. If you pull the carrier you will have to reset the backlash since that is set by the distance between the pinion and the ring. That is pretty easy, just need a base and dial indicator. Once you get that set, just tighten the side bearing preload adjusters equally to and tap the caps with a hammer to seat them. (I got that off of ZUKs website).

So short version, if you don't mess with the pinion then I wouldn't worry about pattern, but if you pull the carrier, backlash and side bearing preload will need to be checked and set. If the pinon has a solid spacer, then even if you do pull it, as long as you don't loose the shim stack or pull the inner bearing, then it should all go back together just how it came out. (that's the beauty of the solid spacer) Also makes replacing the pinion seal a breeze since you don't have to worry about over-crushing the sleeve.
 
EDIT: Jynx got to it before I could finish so that I'll add a few more comments. Regarding pattern, for the most part I agree with his post but not entirely. If the ring gear is set too far away from the pinion gear upon reassembly you will get teeth skipping/jumping while under pressure and ultimately destroy the R&P. You need to get it back to its original position as closely as possible.



You can if you're very very careful and mark everything well ahead of time. I'll say this though, for the most part we've been successful doing this but not 100%.

We take a lot of pictures for reference before and as we pull it apart so we can double check our work during re-assembly.

This is important, We take a punch (NOT a pen or sharpie!!!!!!!!) and mark each side with either a 1-punch mark or a 2-punch mark depending on the side, this is to ensure everything goes back together exactly (X-ing fingers) as before it was taken apart. We'll mark bolts, clips, diff nuts, etc... Notice the single punch mark in the red circle.

Once you have it all apart pull the ring gear and get to installing the locker. Oh, and NO we don't bother marking the bolts on the ring gear but we do mark the ring and the carrier so it goes back together in the exact same relation to each other.

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Then we mark the exact locations of the differential nut on each side and the to include the threads used for each.

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Notice 2 punches on this side and only 1 on the other side. A little hard to see in the pic but notice the top of the nut is also 2-punched indicating it's exact location.

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EDIT: Jynx got to it before I could finish so that I'll add a few more comments. Regarding pattern, for the most part I agree with his post but not entirely. If the ring gear is set too far away from the pinion gear upon reassembly you will get teeth skipping/jumping while under pressure and ultimately destroy the R&P. You need to get it back to its original position as closely as possible.



You can if you're very very careful and mark everything well ahead of time. I'll say this though, for the most part we've been successful doing this but not 100%.

We take a lot of pictures for reference before and as we pull it apart so we can double check our work during re-assembly.

This is important, We take a punch (NOT a pen or sharpie!!!!!!!!) and mark each side with either a 1-punch mark or a 2-punch mark depending on the side, this is to ensure everything goes back together exactly (X-ing fingers) as before it was taken apart. We'll mark bolts, clips, diff nuts, etc... Notice the single punch mark in the red circle.

Once you have it all apart pull the ring gear and get to installing the locker. Oh, and NO we don't bother marking the bolts on the ring gear but we do mark the ring and the carrier so it goes back together in the exact same relation to each other.

View attachment 1208982


Then we mark the exact locations of the differential nut on each side and the to include the threads used for each.

View attachment 1208988


Notice 2 punches on this side and only 1 on the other side. A little hard to see in the pic but notice the top of the nut is also 2-punched indicating it's exact location.

View attachment 1208989

Thanks for the detailed response Ted. Unfortunately, I am going to take the easy way out and pay someone competent to do it. I'd like to learn and will hopefully get the chance to do help someone with experience do an install.
 
Last stupid diff related question, I promise. What is the consensus on the method for sealing the diff upon reinstallation: gasket + RTV (or something similar) or RTV only? I imagine the green (I think) RTV for gear oil applications would be the preference. It seems the internet is divided on gasket vs. no gasket.
 
Toyota Red FIPG is what I use on mine, No gasket.
 

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