[Poncho167]

Since you only drive it about 1000 miles a year and have been doing fine w/o limited slip or the hop shock, don't waste the money adding them now. Doesn't sound like you need or use either of them. If this was a performance build that would be a different story. I agree repairing your existing axle sounds like a waste of money since it's whined for a long time. Probably not set up correctly from the factory.
If it were mine I get a GU6 3.42 ratio out of a junkyard 2wd 4.3 98 up S10 and swap it in. Couple hours work and a couple hundred bucks. It'll likely out live the rest of the truck. I've only had one failure in 37 years of driving S10's and it was just the cheap azz G80 posi not working. Spent over $500 putting in a Zexel.
If it's not a loud whine just drive it. Since you use it so little it'll be years before anything actually breaks.
Maybe drain the rearend to check for any metal and put some Royal Purple synthetic gear lube in. That might quiet it.
BTW the fill plug on the side is not 3/8" and you can round corner it using one trying to remove it. Get a cheap 10mm drain plug socket off ebay and avoid a major hassle.

On the original post I mentioned the first thing I did before its initial service was change the oil. After taking it back following the first service at no additional expense, it was still not 100% but livable until last fall. I would not drive it when I can hear it from inside the truck. I haven't installed a rear end in many years and would rather pay someone if it came to that. A junk yard rear end tells no tales and may be hard to identify which one it is.

 

[goes2fast]

If the sticker is still in the glove box you can identify what rear is in the truck. That is how I identified the 8.5 that I am putting in my truck. As long as the junkyard is willing to warranty it as good and not noisy you should be ok. I rebuilt mine because I wanted a taller gear ratio for fuel economy and to deal with the added horsepower when I install my LS. Plus I plan on keeping my truck until I can no longer drive so I wanted it to be dependable.

 

[Rhotpursuit]

If the sticker is still in the glove box you can identify what rear is in the truck. That is how I identified the 8.5 that I am putting in my truck. As long as the junkyard is willing to warranty it as good and not noisy you should be ok. I rebuilt mine because I wanted a taller gear ratio for fuel economy and to deal with the added horsepower when I install my LS. Plus I plan on keeping my truck until I can no longer drive so I wanted it to be dependable.

When you say the SPID identified the rear, I assume you meant gear ratio and LSD....not the size.

 

[goes2fast]

When you say the SPID identified the rear, I assume you meant gear ratio and LSD....not the size.

Correct but I don't think he would mind going to an 8.5 if it was available for a reasonable price and the ratio was correct.

 

[Poncho167]

If the sticker is still in the glove box you can identify what rear is in the truck. That is how I identified the 8.5 that I am putting in my truck. As long as the junkyard is willing to warranty it as good and not noisy you should be ok. I rebuilt mine because I wanted a taller gear ratio for fuel economy and to deal with the added horsepower when I install my LS. Plus I plan on keeping my truck until I can no longer drive so I wanted it to be dependable.

I already know it came with the 8.5 and based on identification with the tabs at the bottom of the pumpkin it is an 8.5, but what I don't know is if it is the original one? It is missing the third shock that comes with the ZQ8 sport package and after several reviews I still do not see where it would attach going from the rear end forward. 67Truckin said it would horizontal by the bed crossmember but all I see there is what looks to be a factory exhaust hanger to support the muffler/exhaust.

 

[Rhotpursuit]

If you look at the ebay link I posted, you should be able to figure out where it goes. As was stated before...not all ZQ8 trucks got them. The only trucks I know got them without fail were the 96-98 SS trucks....and all of them came with the 7.5 rear end. I'm not even sure if the holes are in the frame for the bracket.

 

[goes2fast]

Is your truck stick or automatic? If I remember correctly only stick trucks had the hop shock so that may be the reason you don't have the bracket on the frame and someone may have upgraded to the 8.5 from a stick truck.

 

[Rhotpursuit]

Is your truck stick or automatic? If I remember correctly only stick trucks had the hop shock so that may be the reason you don't have the bracket on the frame and someone may have upgraded to the 8.5 from a stick truck.

See the post above...there seems to be no rhyme or reason to hop shocks. Doesn't mean the rear couldn't have had the bracket...they do some silly things.

 

[Poncho167]

If you look at the ebay link I posted, you should be able to figure out where it goes. As was stated before...not all ZQ8 trucks got them. The only trucks I know got them without fail were the 96-98 SS trucks....and all of them came with the 7.5 rear end. I'm not even sure if the holes are in the frame for the bracket.

I will take another look but I don't think there is a spot straight inline with the rear end bracket.

 

[Poncho167]

Is your truck stick or automatic? If I remember correctly only stick trucks had the hop shock so that may be the reason you don't have the bracket on the frame and someone may have upgraded to the 8.5 from a stick truck.

-
It's an automatic - 4L60.

 

[Rhotpursuit]

I will take another look but I don't think there is a spot straight inline with the rear end bracket.

There is...

 

[Poncho167]

See the post above...there seems to be no rhyme or reason to hop shocks. Doesn't mean the rear couldn't have had the bracket...they do some silly things.

I took one last look and yes, there are two unused bolt holes in the frame before the leaf spring attachment. I compared some online pictures to where that bracket attaches to the frame and it looks like that would be it. The bolt spacing is 6.5" and that is visually what that frame bracket looks like as well.

 

[Rhotpursuit]

Bingo...

 

[goes2fast]

-
It's an automatic - 4L60.

Then most likely that is not the original rear axle all the automatics I have seen do not have the hop shock. I have never had any wheel hop on mine when I get on it so I think the engineers decided it was only needed on the sticks where there would be more violent launches.

 

[Poncho167]

Then most likely that is not the original rear axle all the automatics I have seen do not have the hop shock. I have never had any wheel hop on mine when I get on it so I think the engineers decided it was only needed on the sticks where there would be more violent launches.

Maybe so, but now I have a rear end with the shock attachment and two holes in the frame for the frame bracket. Based on what you said then I would think all of the frames are predrilled for that 3 shock bracket? Also, I don't know enough about the ZQ8 sport suspension and if the 3 shock package was only for 5-speed trannies. I kind of suspected the rear end was changed out previously based on too much tire spinage, especially around corners at speed, but then again it was said here that it takes a certain amount of time before the OEM LSD locks up. Also, I read years ago that it wasn't uncommon for the LSD to wear out.

 

[Rhotpursuit]

Apparently my laptop prints in invisible ink. This whole hop shock debate has been going on since day one. All 96-98 SS's got it. Some ZQ8's got it. There seems to be no concrete documentation as to what did ,or what did not get one. What difference does it make anyway? If you want one...get one. Plenty of guys have the axle bracket and nothing else. Doesn't mean it was changed out.

 

[Mostizzle]

I'll sell you a bracket and shock for one meeeellion dollars!

 

[goes2fast]

Maybe so, but now I have a rear end with the shock attachment and two holes in the frame for the frame bracket. Based on what you said then I would think all of the frames are predrilled for that 3 shock bracket? Also, I don't know enough about the ZQ8 sport suspension and if the 3 shock package was only for 5-speed trannies. I kind of suspected the rear end was changed out previously based on too much tire spinage, especially around corners at speed, but then again it was said here that it takes a certain amount of time before the OEM LSD locks up. Also, I read years ago that it wasn't uncommon for the LSD to wear out.

Yes, even though it's called a gov-lock it still has clutches to wear out and in my experience even when new it never worked when you really need it. That is why I replaced mine with a Tru-Trac. When I bought my new S15 Jimmy it was advertised as a locking differential, so I paid extra for it thinking it worked like a Detroit Locker but the first time I went four-wheeling I found out the hard way that they are worthless for slow off-road use since wheel speed is too slow for it to lock. It cost me a rear window on my new truck that only had about 500 miles on it.

I have used nothing but Tru-Trcs and Detroit Lockers ever since and have never had one fail so I think they are well worth the money.

I would think the holes would be in the frame for all applications since when they build the frame they don't know what trans is going in to simplify manufacturing.

 

[goes2fast]

I'll sell you a bracket and shock for one meeeellion dollars!

Not too greedy are we? ? ? ?

 

[goes2fast]

I'll search the junkyards and find you one for 1/2 meeeellion dollars!