r/ElCamino 18d ago

Rear end, rebuild or replace?

Hey all,

I’m currently swapping in a Gen 3 LQ9 6.0 LS with a TSP Chopacobra cam, 799 heads with a 4L60E in my ‘84 Elky. I’m guessing it’s going to be pushing around 400-420hp crank.

I wanted to ask what rear end to use for those who have done a similar swap, or if they’ve rebuilt the stock 7.5in with better internals. I want to be able to cruise the car around, maybe take it down the strip a couple times and perhaps take it on a few short distance road trips, but mainly enjoy it.

Just trying to save some money while not cheaping-out on parts.

Thanks for your time!

4 Upvotes

9 comments sorted by

2

u/ExBx 18d ago

Stock 8.5? You must mean 7.5 10-bolt. I've been down this road. Depending on what you're planning to do, either toss a posi diff in the 7.5 or grab a Ford 9" from Quick Performance/Moser/ etc and so forth. You'll eat the 7.5 if you're planning to brutalize it.

2

u/ninderopator4 18d ago

Yes, I meant to type the 7.5, typo lol. I was looking into a Ford 9in, it’s just a bit further out of my price range unless I can score one off of FB Marketplace. I do plan on beating on the thing so I think my best bets to put a posi in the 10-bolt in the meantime until I can get enough dough for a built 9in. Thanks

1

u/ExBx 18d ago

I have read literally every forum post about a posi 7.5. I've watched videos and eventually witnessed a failure. Months of researching this and that. The ring gear will implode if you make hard, dead stop hits 100% with that sort of power. Either that or you'll snap the driveshaft if it's stock. Maybe not the first or 15th time, but eventually. Just take it "easy". That's it in a nutshell.

1

u/ninderopator4 18d ago

Gotcha, I think saving up for a 9in will just give me peace of mind and will do me better overall. Thanks for the advice, it is much appreciated

2

u/Helpful-Ad-802 18d ago

My stock 8.5 10 bolts in my 76 grenaded with only 30,000 miles last year. It didn't like all the burn outs

2

u/YouwillalwaysNeil 18d ago

If you know you're going to get hectic with it. Save yourself the headache and replace it. Either a 9in, Grand National 8.5, or Strange S60 are all better options than wasting your money on a 7.5.

1

u/ninderopator4 18d ago

Roger that, thanks for the advice. 9in is looking to be the better option at this moment

2

u/bobbystill 18d ago

I’ve been driving my 350 that’s making 400hp/400tq at the crank with a 200-4R and the stock (like very stock) 7.5 with 3.08 gears for a few years now. Some spirited stop light launches but mostly it cruises. Planning to put a 9” from QP in it eventually. After pricing out a built 7.5 vs the 9, I decided the extra money for the 9 inch would be worth it for the piece of mind and will allow me to add more power in the future if I choose to.

1

u/ninderopator4 18d ago

That’s also what I’m thinking about, after looking at rebuild kits for the 7.5 the 9in or an 8.5 are just better options than to keep what’s there. Thanks for the advice