Well that's what my BBC makes just off idle.
CK5
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4.10’s or 4.56’s with 700r4, 35” tires
- Thread starter Chris Ziemer
- Start date
Cubes will do thatWell that's what my BBC makes just off idle.
no . . . 8.1L makes that muchWell that's what my BBC makes just off idle.
Just gotta love them BIG-BLOCKS!Well that's what my BBC makes just off idle.
There was a time when I was content with a really good SBC but then I got right with Jesus and saw the light of them big-ole Chevy motors and I ain’t been the same ever since!
I might have gotten carried away with that one…
Big-Blocks with the proper combination of parts will just ruin you for most any other smaller motors ( disclaimer - motors like 12/24V Cummins are excluded because they are just in a separate class of badass ).
Yes, my 8.1L is a BBC.no . . . 8.1L makes that much
Just adding my $.02.
I’ve been running 4.56 on 37’s and it dogged on hills. Some really steep hills, I dropped to 2nd gear but mostly had to drop to 3rd. Forget about OD and a locked converter.
I’m in the middle of going to 5.13’s. I’ve got the rear done and will doing the front next weekend if it’s not 113 as forecasted. I’ve only put 30 miles on it, but I’m a little better off now.
4.88 may be a better option on 35’s.
Running 1/2 ton axles with 35’s with the vehicle weight is getting to the edge of those axles capabilities. It does depend on how you drive it though. If you drive with finesse and not heavy throttle, you can survive.
Any axle set you get will likely need to be regeared.
I’ve been running 4.56 on 37’s and it dogged on hills. Some really steep hills, I dropped to 2nd gear but mostly had to drop to 3rd. Forget about OD and a locked converter.
I’m in the middle of going to 5.13’s. I’ve got the rear done and will doing the front next weekend if it’s not 113 as forecasted. I’ve only put 30 miles on it, but I’m a little better off now.
4.88 may be a better option on 35’s.
Running 1/2 ton axles with 35’s with the vehicle weight is getting to the edge of those axles capabilities. It does depend on how you drive it though. If you drive with finesse and not heavy throttle, you can survive.
Any axle set you get will likely need to be regeared.
Super appreciate the feedback on that! Looking on Facebook and craigslist for an operating 14 bolt axle set that at least has 410s in it… Something in the right direction so I wouldn’t have to re-gear right away.
At this point, I am thinking about rearing my 10 bolt and just seeing what happens. I am pretty easy on her because I have so many paychecks into it. And, my rear housing was rebuilt last year or so, hopefully a re-gear will do it.
I sure admire those of you who can swap these yourselves. You know, aside from paint, a new motor and tranny someday, some digital gauges, maybe new interior… This will be the last big expense I put into it! 
At this point, I am thinking about rearing my 10 bolt and just seeing what happens. I am pretty easy on her because I have so many paychecks into it. And, my rear housing was rebuilt last year or so, hopefully a re-gear will do it.
I sure admire those of you who can swap these yourselves. You know, aside from paint, a new motor and tranny someday, some digital gauges, maybe new interior… This will be the last big expense I put into it!
Just a thought - instead of putting even more money into your already redone rear axle by regearing it, which is ill advised, you could sell your freshly rebuilt rear axle and put that money towards an axle that has a chance of surviving instead of one that is known for failure even in stock form.
Only trying to lead ya towards the water - it's up to you to drink or not…spend wisely and don't dig a deeper hole that you plan to climb out of eventually.
I have to wonder how much money someone will pay for an axle with 3:08 gears.
I had a 10B in my '90 that didn't fail until 280K, which I don't see as poor longevity. And the old man who had it previously
pulled a small trailer a decent amount.
And I also am one who has almost 50K miles on a 12B behind a big block/700R4 combo. I hits fairly decent on gear changes, and has done a few burnouts. I don't beat on it extremely hard or continuously when I do drive the truck, though. Will it eventually fail, most likely yes.
I can see the advantages of both avenues, swap axles or regear the current ones.
Let's face it, paying to go to 3/4 ton axles, swapping in new gears and different wheels, probably tires, is not cheap. Durable, yes. Not cheap.
No doubt that any axle can last and defy the common press that they’re known for.
Since he’s at a point that mods and upgrades are being sought after and has searched out a quality/trusted forum as CK5 for build advice I believe the suggestion on not reinvesting in the 10B ( which he is planning on swapping out even after the gear swap ) is sound advice.
The original 10B is already a high mileage unit that has been “redone” and that most likely means that just the carrier bearings, pinion seal, brakes and axle seals were replaced.
The original items like the differential, center pin, spider gears and axles would now be asked to deal with the increase of ratio effects and tire size.
Agreed that a 3.08 geared one-legged, step above an S-10 rear end, full-size 10B won’t bring any serious cash but my suggestion was that it would be better to possibly get $350 bones out of it as is, then to invest a grand ( assuming paying labor ) back into an axle that is not intended to ultimately keep.
Putting that money plus whatever he could get for the 10B into a six-lug newer 9.5” 12B would seem wiser advice - also 3/4 Ton axles are no doubt not the answer for every upgrade.
I’m not saying that any axle can’t survive and endure but I am saying that an already old 10B ( even if it has new bearings and such ) is not the axle to sing praises about and suggest that more money and effort be invested into it.
All I’m try’n to get across is that it’s not a good bet.
Would this be a “3.93”, as printed?
Thank you very much.
The “3 93” is the date code - March of 1993.
I’m thinking about just installing this as is and hoping for the best. Rebuilding it down the road. It is on a roller right now. Would I have to move spring perches and shock mounts for my 82?
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What is the roller that it’s under now?
It’s on a 75 Blazer. Guy basically bought it for the title and body and magically changed his current rig into a smog exempt.
Hmmm, I think I see where you’re getting at.
Hmmm, I think I see where you’re getting at.
IIRC all 73~87 K5’s & K10/20’s have a rear spring pad center to center width of 42.5”.
If this rear axle was a transplant from something other than a square ( and judging by the way the shocks are bolted up it is ) you might want to verify that they got the pinion angle right.
This 9.5” semi-floater axle ( I assume it’s a 6-lug version ) is a good foundation to build upon.
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Page 5 of a thread about gear ratios and you're going with 3.42?
I’m just going to go with it and get it installed. Itll push my 4:56 gears out a little, but when I’m ready again, I’ll have this beefcake in there.
It’ll probably cost me a grand for the axle and proper install, as it is.
When I decide to rebuild and re-gear the axle, it’ll cost me another $1000 to $1200.
It’ll probably cost me a grand for the axle and proper install, as it is.
When I decide to rebuild and re-gear the axle, it’ll cost me another $1000 to $1200.
