Rearend rebuilt and trying to assemble - AXLE RETAINING PIN WON'T SLIDE IN!!

[caseywan]

I just finished rebuilding the 8.8 in my 02 Sport Trac and am trying to reassemble it, but the c-clip/axle retaining pin positively will not slide back in. I have had apart dozens of 8.8's in the past and know how to rebuild them, but something is just not right here.

I insert the axles, slide on the c-clips, pull the axles back out so that the c-clips fully seat inside the spider gears, and then the retaining pin is hitting both axles and needs about 1/16 on each side to slide all the way through.

I did buy a new differential and rebuild it, but I cannot figure out how that would change anything.

I started hearing this bad clunking in the rear and tore into it and found my spider gears were all chewed up. Rather than buying new spider gears for $125, I bought a used 31 spline OEM carrier with a carbon fiber clutch rebuild kit for $100 off eBay.

The carrier I bought was said to be a 31 spline Explorer carrier, and as far as I can tell it is - I have never known there to be any differences in 8.8's. Are they not all the same?

I am tempted to just grind the ends of the axles down by 1/16, but there is something in the back of my mind telling me that is not a good idea...

 

[IZwack]

If you are replacing the sider gears - compare the height between the old and the new. Remember that the clutch discs, which make up the Limited Slip portion of the differential, spaces the two side spider gears in towards the center - which would potentially make it impossible to reinstall the C-clips if they are too thick and also make it impossible for the cross pin to pass through.

Also, since you asked if all 8.8s are the same, no the LSD carrier is different from the open carrier.

 

[caseywan]

If you are replacing the sider gears - compare the height between the old and the new. Remember that the clutch discs, which make up the Limited Slip portion of the differential, spaces the two side spider gears in towards the center - which would potentially make it impossible to reinstall the C-clips if they are too thick and also make it impossible for the cross pin to pass through.

Also, since you asked if all 8.8s are the same, no the LSD carrier is different from the open carrier.

If the thickness of the shims/clutches made that big of a difference, wouldn't it keep the smaller spider gears from fitting?

Both carriers, the original the the new one were LSD carriers.

 

[IZwack]

Well some people stack extra clutch discs behind the spiders so they can get better traction off road. So this probably means the thickness of the discs are undefined and differ between manufacturers.

I know its probably a pain but I would remove and compare the new vs the old parts using a vernier caliper.

 

[caseywan]

I know its probably a pain but I would remove and compare the old parts vs the new.

Yep, guess that's what I'm gonna have to do. Just as long as I don't have to pay to have the backlash and all that set up again...

Also, since I will more than likely have to take the ring gear back off the carrier again - can I reuse the ring gear bolts again, or should I use loctite? I used the new bolts that came with the rebuild kit that had the thread locking stuff on them already...

 

[IZwack]

You're not supposed to reuse the ring gear bolts but I would - just dont forget the Loctite. There's like what, at least six of those bolts? It would be difficult to shear them provided they dont back off.

 

[caseywan]

You're not supposed to reuse the ring gear bolts but I would - just dont forget the Loctite. There's like what, at least six of those bolts? It would be difficult to shear them provided they dont back off.

Yeah, I was thinking you weren't really supposed to reuse them, but ya there's 10 of them, I don't think it's going to be an issue.

 

[HahnsB2]

On my old 7.5 I reused the ring gear bolts and didn't use loc-tite, never had a problem! Ignorance is bliss

 

[caseywan]

So, I half a$$ed it...

Pulled the axles out and ground off a 32nd off each axle end, being careful not to get them hot by doing it little by little.

Like I said, it only took off 1/32 of an inch off each end, so it shouldn't have done anything to the integrity of the axle.

 

[gijoecam]

I suspect that the side gears weren't correct... Keep in mind that the axles could now be riding farther in-board of where they were originally... not sure if that could cause a clearance issue (doubt it, but...?) but it's worth watching closely.