Rear end swap ????

[66/87chevy]

Any info out there on what rear end would be a direct swap to go in my new to me 85 c10.

It has the stock 10 bolt with 2.73 gear in it now. I'd like to go to a beefier axle and a 4.10 or 4.11 gears. What is available for these trucks?

[77ChevySharkBite]

Originally Posted by 66/87chevy

Any info out there on what rear end would be a direct swap to go in my new to me 85 c10.

It has the stock 10 bolt with 2.73 gear in it now. I'd like to go to a beefier axle and a 4.10 or 4.11 gears. What is available for these trucks?

well you could do a 12 bolt, or go with a ford 9' rear end, or just do a gear swap.

[Ziegelsteinfaust]

The 12 bolt is not much of an improvement over a 8.5 10 bolt that you have.

4.11 gears are $250ish from most suppliers, and while at it I would rebuild my rear end. Then toss in some better axles, and posi. So you be good to go for quite a bit of HP/TQ.

[66/87chevy]

Yeah I was thinking of doing a gear swap and replacing everything that is wore. But I was kind of hoping I could score on a complete rear end off of a different vehicle that already had the 4.11 posi The local wrench-N-Go has a few newer rear ends to chose from but I'm not sure if I could just swap them with out any major fabrication.

[Blackpony]

If you are handy with tools and setting up a set of gears, there is a killer deal on ebay with bearings, limited slip and gears. let me see if I can find it again.

here you go. They also offer this with a 30 spline limited slip unit

http://www.ebay.com/itm/GM-8-5-10-Bo...cfda23&vxp=mtr

[66/87chevy]

Originally Posted by Blackpony

If you are handy with tools and setting up a set of gears, there is a killer deal on ebay with bearings, limited slip and gears. let me see if I can find it again.

here you go. They also offer this with a 30 spline limited slip unit

http://www.ebay.com/itm/GM-8-5-10-Bo...cfda23&vxp=mtr

That is a pretty good, but Dang!!!! That's darn near what I paid for my 85 roller.

I will look into what tools I'd need, and see if I think it's something I can do my self.
Thanks for the link.
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[LONGHAIR]

Originally Posted by 66/87chevy

I will look into what tools I'd need, and see if I think it's something I can do my self.
Thanks for the link.
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With-out previous experience, plain and simple....no.
And if the price of the parts gives you sticker shock, you are better-off with swapping the entire axle housing assembly. Just be aware that the later model axles do not have a "true" posi-traction unit. They are equipped with the G-80 (Gov-loc), not the strongest piece out there. They are prone to failure, especially with higher horsepower, bigger tires, or aggressive driving.

[low82c10]

So it's better to replace inside parts or find something in junk yard.
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[SCOTI]

Originally Posted by low82c10

So it's better to replace inside parts or find something in junk yard.
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Its better to replace the internals & build to spec.... A junkyard/craigslist score is usually a gamble unless you're @ the right place & time.

[LONGHAIR]

Originally Posted by low82c10

So it's better to replace inside parts or find something in junk yard.
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"Pay a pro" to replace internal parts, not a DIY job.

[franken]

If you've got self serve scrap yards, I'd expect you have a great selection.

Measure or research the wheel bolt pattern.
Measure from close to the ubolt outside of the spring to the same place on the other side on the inside of the spring. This should be the center to center perch difference.
Measure the width of the spring.
Measure the outside of the spring to the wheel mount surface. Or measure directly.
Add the perch measurement, spring width plus 2X the outside of the spring to WMS for WMS-WMS.

Go the the scrapyard and find rears with that bolt pattern, with same perch center to center and close WMS.

I explain things poorly, so, sorry.

[wraprail]

1979 Ford Torino uses a 9inch same width & bolt pattern (5x5) as our trucks. You need to remove all the brackets and crap from it and weld some leaf spring pads on it.
Lincoln Mark V has same rear end but with disc brakes.

[66/87chevy]

Originally Posted by wraprail

1979 Ford Torino uses a 9inch same width & bolt pattern (5x5) as our trucks. You need to remove all the brackets and crap from it and weld some leaf spring pads on it.
Lincoln Mark V has same rear end but with disc brakes.

Thanks for the info, good to know.....

[Sodell]

3.73's are pretty abundant for the C10, not 4.11 but closer to what you are looking for.

[esbstuff]

Originally Posted by 66/87chevy

Any info out there on what rear end would be a direct swap to go in my new to me 85 c10.

It has the stock 10 bolt with 2.73 gear in it now. I'd like to go to a beefier axle and a 4.10 or 4.11 gears. What is available for these trucks?

Go with the 12 as its almost a bolt in. Lots of them are available. VERY big interchange if you can DIY almost anything. Just make sure you pickup a 5 luger as your 10 bolt axles would not work in the 12

If you want 4.10's you will almost have to buy new gears as they are a rare find stock.

I personally like 3.42's in a driver a good all around gear. Gives you pull as needed, but still fuel friendly. 3.73's 4.10's ok as a driver IF you have OD trans.

But everything depends on motor/trans/primary use of the truck...

$250 should get you a nice 12 easily.

[low82c10]

i just put a 5.3 in my square, it seems like its at a high RPM on the highway, i havent checked what gears i have but would be a good gear to go with? its got the 4l60e and i want to be able to just cruse at about 2000rpm at about 75-80 like it does in the stock truck.

[LONGHAIR]

Originally Posted by low82c10

i just put a 5.3 in my square, it seems like its at a high RPM on the highway, i havent checked what gears i have but would be a good gear to go with? its got the 4l60e and i want to be able to just cruse at about 2000rpm at about 75-80 like it does in the stock truck.

Uh, what gear was in the truck it came from?

[low82c10]

im sure stock gears, the motor came out of a 2004 tahoe

[INSIDIOUS '86]

Why would anyone bother with a power robbing ford 9 in a truck unless you got 800+hp?

Suburbans from what I have seen are typically lower geared and several get beaten and scrapped before any real miles get into them which is nice. At least up here that's the case.

Later ten bolts have bigger axles and are only marginally weaker than a car 12 bolt. Which if turbo gnx guys can turn 9s with them with bolt ins its good enough for me
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[wraprail]

Originally Posted by INSIDIOUS '86

Why would anyone bother with a power robbing ford 9 in a truck unless you got 800+hp?

Not sure what you mean dude. Ford 9 inch is used in more swaps, more often then any other rear end by far. The aftermarket makes more products. Everything from golf carts to high end race cars use them.
What do you know that everyone else has missed?
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[Blackpony]

Originally Posted by wraprail

Not sure what you mean dude. Ford 9 inch is used in more swaps, more often then any other rear end by far. The aftermarket makes more products. Everything from golf carts to high end race cars use them.
What do you know that everyone else has missed?
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I think he is saying that a ford 9 inch isn't always the best answer. You can build a 10 bolt to hold great power with less parasitic loss for the same or less money.
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[INSIDIOUS '86]

^ exactly. That and it's gm and a direct bolt in. Unless you need a niner why bother? Kinda how I think. But again we don't exactly know the intentions purpose or use exactly of the OP
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[66/87chevy]

Originally Posted by INSIDIOUS '86

^ exactly. That and it's gm and a direct bolt in. Unless you need a niner why bother? Kinda how I think. But again we don't exactly know the intentions purpose or use exactly of the OP
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My 85 c10 is going to have a mild built BB with a th350 behind it.... This is NOT a truck that I will be taking road trips with. With that being said I want this truck to be able to go from 0-100mph as quick as possible. That's why I'm thinking of going with 4.11 gears.

[INSIDIOUS '86]

Originally Posted by 66/87chevy

My 85 c10 is going to have a mild built BB with a th350 behind it.... This is NOT a truck that I will be taking road trips with. With that being said I want this truck to be able to go from 0-100mph as quick as possible. That's why I'm thinking of going with 4.11 gears.

Depending on tire size 100mph may be all you get too haha. My 3:73s with 26" tires gets me to 115mph at 6krpm. A c clip eliminator and 30 spline axles with a t/a bearing girdle and differential of choice will handle 600hp reliably and when the tubes are welded do fine under the trans take and 700hp turbo gnx cars nice thing is the 8.5 ten can do alot and it's already under almost every truck.

Want to get to 100 really quick gears -weight+hp makes that happen quick haha
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[manimal]

The ONLY advantages a 9" has(other than pinion strength) over a GM rear axle is you can change gear ratios VERY quickly.(1hr if you're slow). Have your highway gears in one chunk,and your street/racing gears in another. simple as that.